Patent Publication Number: US-10779887-B2

Title: Systems and methods for creating an effect using microwave energy to specified tissue

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 15/252,109, filed Aug. 30, 2016, now U.S. Pat. No. 10,166,072; which application is a continuation of U.S. application Ser. No. 12/107,025, filed Apr. 21, 2008, now U.S. Pat. No. 9,427,285; which application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application No. 60/912,899 filed Apr. 19, 2007; U.S. Provisional Application No. 61/013,274, filed Dec. 12, 2007; and U.S. Provisional Application No. 61/045,937, filed Apr. 17, 2008. All of the above priority applications are expressly incorporated by reference in their entirety. 
     application Ser. No. 12/107,025 also claims priority to PCT Application No. PCT/US08/060935, filed Apr. 18, 2008; PCT Application No. PCT/US08/060929, filed Apr. 18, 2008; PCT Application No. PCT/US08/060940, filed Apr. 18, 2008; and PCT Application No. PCT/US08/060922, filed Apr. 18, 2008. All of the above PCT priority applications are also expressly incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     Field of the Invention 
     The present application relates to methods, apparatuses and systems for non-invasive delivery of microwave therapy. In particular, the present application relates to methods, apparatuses and systems for non-invasively delivering microwave energy to the epidermal, dermal and subdermal tissue of a patient to achieve various therapeutic and/or aesthetic results. 
     Description of the Related Art 
     It is known that energy-based therapies can be applied to tissue throughout the body to achieve numerous therapeutic and/or aesthetic results. There remains a continual need to improve on the effectiveness of these energy-based therapies and provide enhanced therapeutic results with minimal adverse side effects or discomfort. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustration of a cross-section of human tissue structures. 
         FIG. 2  illustrates a system for generating and controlling microwave energy according to one embodiment of the invention. 
         FIG. 3  illustrates a system for delivering microwave energy according to one embodiment of the invention. 
         FIG. 4  is a side perspective view of a microwave applicator according to one embodiment of the invention 
         FIG. 5  is a top perspective view of a microwave applicator according to one embodiment of the invention. 
         FIG. 6  is a front view of a microwave applicator according to one embodiment of the invention. 
         FIG. 7  is a front view of a tissue head for use with a microwave applicator according to one embodiment of the invention. 
         FIG. 8  is a cutaway view of a tissue head according to one embodiment of the invention. 
         FIG. 9  is a side cutaway view of a microwave applicator according to one embodiment of the invention. 
         FIG. 10  is a top perspective partial cutaway view of a microwave applicator according to one embodiment of the invention. 
         FIG. 11  is a side partial cutaway view of a microwave applicator according to one embodiment of the invention. 
         FIG. 12  is a cutaway view of a tissue head and antenna according to one embodiment of the invention. 
         FIG. 13  is a cutaway view of a tissue head and antenna according to one embodiment of the invention. 
         FIG. 14  is a cutaway view of a tissue head, antenna and field spreader according to one embodiment of the invention. 
         FIG. 15  is a cutaway view of a tissue head, antenna and field spreader according to one embodiment of the invention. 
         FIG. 16  is a cutaway view of a tissue head, antenna and field spreader according to one embodiment of the invention. 
         FIG. 17  is a cutaway view of a tissue head, antenna and field spreader according to one embodiment of the invention. 
         FIG. 18  is a cutaway view of a tissue head, antenna and field spreader according to one embodiment of the invention. 
         FIG. 19  is a cutaway view of a tissue head, antenna and field spreader with tissue engaged according to one embodiment of the invention. 
         FIG. 20  is a cutaway view of a tissue head and antenna and with tissue engaged according to one embodiment of the invention. 
         FIG. 21  illustrates a tissue head including a plurality of waveguide antennas according to one embodiment of the invention. 
         FIG. 22  illustrates a tissue head including a plurality of waveguide antennas according to one embodiment of the invention. 
         FIG. 23  illustrates a tissue head including a plurality of waveguide antennas according to one embodiment of the invention. 
         FIG. 24  illustrates a disposable tissue head for use with an applicator according to one embodiment of the invention. 
         FIG. 25  illustrates a disposable tissue head for use with an applicator according to one embodiment of the invention. 
         FIG. 26  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 27  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 28  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 29  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 30  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 31  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 32  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 33  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 34  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 35  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 36  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 37  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 38  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 39  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 40  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 41  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 42  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 43  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 44  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 45  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 46  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 47  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 48  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 49  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 50  illustrates a tissue profile according to one embodiment of the invention. 
         FIG. 51  illustrates a tissue profile according to one embodiment of the invention. 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     When skin is irradiated with electromagnetic radiation, such as, for example, microwave energy, energy is absorbed by each layer of tissue as the electromagnetic radiation passes through the tissue. The amount of energy absorbed by each tissue layer is a function of a number of variables. Some of the variables which control the amount of energy absorbed in each tissue layer include: the power of the electromagnetic radiation which reaches each layer; the amount of time each layer is irradiated; the electrical conductivity or loss tangent of the tissue in each layer and the radiation pattern of the antenna radiating the electromagnetic energy. The power which reaches a particular layer of tissue is a function of a number of variables. Some of the variables which control the power reaching a particular layer of tissue include the power impinging upon the surface of the skin and the frequency of the electromagnetic radiation. For example, at higher frequencies the penetration depth of the electromagnetic signal is shallow and most power is deposited in the upper layers of tissue, at lower frequencies, larger penetration depths result in power deposition in both upper and lower tissue layers. 
     Heat may be generated in tissue by a number of mechanisms. Some of the mechanisms for generating heat in tissue include resistive heating, dielectric heating and thermal conduction. Resistive heating occurs when electrical currents are generated in the tissue, resulting in resistive losses. Tissue may be resistively heated using, for example, mono-polar or bi-polar RF energy. Dielectric heating occurs when electromagnetic energy induces an increased physical rotation of polar molecules that converts microwave energy into heat. Tissue may be dielectrically heated by, for example, irradiating the tissue with electromagnetic energy in the microwave frequency band. As used herein, microwave frequency band or microwave frequencies may refer to, for example, electromagnetic energy at frequencies which are suitable for inducing dielectric heating in tissue when that tissue is irradiated using an external antenna to transmit the electromagnetic radiation. Such frequencies may be in the range of, for example, from approximately 100 Megahertz (MHz) to 30 Gigahertz (GHz). Whether tissue is heated by resistive heating or by dielectric heating, heat generated in one region of tissue may be transmitted to adjacent tissue by, for example, thermal conduction, thermal radiation or thermal convection. 
     When a microwave signal is radiated into a lossy dielectric material such as water, the energy of the signal is absorbed and converted to heat as it penetrates the material. This heat is primarily generated by induced physical rotation of molecules when subjected to the microwave signal. The efficiency of the conversion of microwave energy into heat for a given material can be quantified by the energy dissipation factor, or loss-tangent (tan □). The loss-tangent varies as a function of material composition and the frequency of the microwave signal. Water has a large loss-tangent and heats efficiently when irradiated with microwave energy. Since all biological tissue has some water content, and thus is lossy, it can be heated using microwave energy. Different tissue types have varying amounts of water content, with muscle and skin having a relatively high water content and fat and bone having significantly less water content. Microwave heating is generally more efficient in high water content tissues. 
     The application of RF energy, which is conducted through the surface of the skin, or microwave energy, which is radiated through the surface of the skin, to heat tissue below the skin surface generally results in a temperature gradient having a peak at the surface of the skin and decreasing with increasing depth into the tissue. That is, the hottest point is generally found at or near the surface of the skin. The temperature gradient results from the power lost by the electromagnetic radiation as it moves through the tissue. The power loss density profile generally peaks in tissue at the skin surface and declines as the electromagnetic radiation moves through the tissue, regardless of the radiated power or frequency of the electromagnetic radiation. Power loss density is measured in watts per cubic meter. An equivalent characterization of power deposition in tissue is the Specific Absorption Rate (SAR) which is measured in watts per kilogram. Specific absorption rate in tissue may be, for example, proportional to the square of the magnitude of electric field in that tissue. For a fixed radiated power level the penetration depth will generally decrease as the frequency increases. Thus, as a general principal, to heat tissue near the skin surface, such as, for example, the epidermis, without damage to deeper tissue layers one would generally select a higher frequency. Further, as a general principal, to heat tissue deep within the skin, such as, for example, in the deep dermis or the hypodermis, or below the skin surface, such as, for example, in muscle tissue, one would generally select a lower frequency to ensure that sufficient energy reached the deeper tissue. 
     Where electromagnetic energy is being used to heat structures in tissue below the skin surface and it is desirable to limit or prevent damage to the skin surface or tissue adjacent the skin surface, it is possible to modify the temperature gradient to move the peak temperature deeper into the tissue. Temperature gradients within tissue may be modified to move the peak temperature into tissue below the skin surface by, for example, using external mechanisms to remove heat from tissue close to the skin surface. External mechanisms which remove heat from the surface of the skin may include, for example, heat sinks which cool the skin surface and adjacent layers. When external mechanisms are used to remove heat from the surface of the skin, the heat may be removed as the electromagnetic radiation deposits energy into that tissue. Thus, where external mechanisms are used to remove heat from the surface of the skin and adjoining layers, energy is still absorbed at substantially the same rate by tissue adjacent the skin surface (and the power loss density and SAR in the cooled tissue remain substantially constant and are not effected by cooling) but damage is prevented by removing heat faster than it can build up, preventing the temperature of the cooled tissue, for example, tissue adjacent the skin surface, from reaching a temperature where tissue damage occurs or a lesion could form. 
       FIG. 1  is an illustration of human tissue structure. In the embodiment of the invention illustrated in  FIG. 1 , muscle tissue  1301  is connected to hypodermis  1303  by connective tissue  1302 . Hypodermis  1303  is connected to dermis  1305  at interface  1308 . Epidermis  1304  lies over dermis  1305 . Skin surface  1306  lies over epidermis  1304  and includes squamous epithelial cells  1345  and sweat pores  1347 . Tissue structures  1325  such as, for example, sweat glands  1341 , sebaceous glands  1342  and hair follicles  1344 , may be positioned throughout dermis  1305  and hypodermis  1303 . Further, tissue structures  1325  may be positioned such that they cross or interrupt interface  1308 .  FIG. 1  further includes artery  1349 , vein  1351  and nerve  1353 . Hair follicle  1344  is attached to hair shaft  1343 . Tissue structures such as, for example, apocrine glands, eccrine glands or hair follicles may be expected to have sizes in the range of, for example, between approximately 0.1 millimeter and two millimeters and may group together to form groups or structures having even larger sizes. As illustrated in  FIG. 1 , interface  1308  may be expected to be a non-linear, non-continuous, rough interface which may also include many tissue structures and groups of tissue structures which cross and interrupt interface  1308 . When modeling tissue layers such as, for example the dermis, it is difficult to accurately model the permittivity (e.g., dielectric constants) and/or conductivity characteristics of the tissue layers because of the variability from person to person and within body regions of individuals. In addition, the presence of tissue structures and of groups of tissue structures creates additional complexities. Assuming an average dielectric constant for a particular layer does not generally reflect the complexity of the actual tissue, however, it may be used as a starting point. For example, assuming a dielectric constant of, for example, approximately 66 for dermal tissue at 100 MHz, electromagnetic energy at the low end of the microwave range, would have a wavelength of approximately 370 millimeters. Assuming a dielectric constant of, for example, approximately 38 for dermal tissue at 6.0 GHz, electromagnetic energy would have a wavelength of approximately 8 millimeters in dermal tissue. Assuming a dielectric constant of, for example, approximately 18 for dermal tissue at 30 GHz, electromagnetic energy at the high end of the microwave range would have a wavelength of approximately 2.5 millimeters in dermal tissue. Thus, as frequency increases, the presence of rough, discontinuous interfaces between tissue regions and the presence of tissue structures and groups of tissue structures will result in unpredictable scattering of at least some of the signal when it encounters tissue structures, groups of tissue structures or discontinuous tissue interfaces. For a fixed size tissue structure, group of structures or discontinuity, scattering generally increases as wavelength decreases and becomes more pronounced when wavelength is within an order of magnitude of the size of tissue structures, groups of tissue structures or discontinuities in the interface. At low frequencies, the wavelength of the signal is long enough that it would reflect off the interface without substantial unpredictable scattering. 
     When electromagnetic energy is transmitted through a medium having structures and interfaces, including interfaces between tissue layers, the electromagnetic energy will, depending upon the electrical and physical characteristics of the structures, groups of structures and interfaces, and the differences between electrical and physical characteristics of such structures, groups of structures and interfaces and surrounding tissue, be scattered and/or reflected by the structures, groups of structures and/or interfaces. When reflected electromagnetic waves interact with incident electromagnetic waves they may, under certain circumstances, combine to form a standing wave having one or more constructive interference peaks, such as, for example an E-field peak, and one or more interference minimums (also referred to as regions of destructive interference). However, scattering will tend to minimize or destroy such constructive interference peaks. 
     In modeling tissue for the purposes of the present discussion dermal tissue may be modeled to include a dermis and an epidermis. In modeling tissue for the purposes of the present discussion dermal tissue may be modeled to have a conductivity of approximately 4.5 siemens per meter at approximately 6 GHz. In modeling tissue for the purposes of the present discussion dermal tissue may be modeled to have a dielectric constant of approximately 40 at approximately 6 GHz. In modeling tissue for the purposes of the present discussion hypodermal tissue may be modeled to have a conductivity of approximately 0.3 siemens per meter at approximately 6 GHz. In modeling tissue for the purposes of the present discussion hypodermal tissue may be modeled to have a dielectric constant of approximately 5 at approximately 6 GHz. 
     Systems and Apparatuses 
       FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate heat in selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined specific absorption rate profiles in selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined specific absorption rate profiles such as, for example, the specific absorption rate profiles illustrated in  FIGS. 26 through 51 .  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined specific absorption rate or power loss density profiles in selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined power loss density profiles such as, for example, the power loss density profiles illustrated in  FIGS. 26 through 51 . 
       FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined temperature profiles in selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to generate predetermined temperature profiles such as, for example, the temperature profiles illustrated in  FIGS. 26 through 51 . 
       FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected regions by generating specific absorption rate profiles with a peak in the selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected tissue by generating specific absorption rate profiles such as, for example, the specific absorption rate profiles illustrated in  FIGS. 26 through 51 , wherein the lesion is created in region of the tissue corresponding to the peak specific absorption rate.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected regions by generating power loss density profiles with a peak in the selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected tissue by generating power loss density profiles such as, for example, the power loss density profiles illustrated in  FIGS. 26 through 51 , wherein the lesion is created in region of the tissue corresponding to the peak power loss density.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected regions by generating temperature profiles with a peak in the selected tissue regions.  FIGS. 2 through 25 and 48 through 51  illustrate embodiments and components of embodiments of systems according to the invention which may be used to create lesions in selected tissue by generating temperature profiles such as, for example, the temperature profiles illustrated in  FIGS. 26 through 51  wherein the lesion is created in region of the tissue corresponding to the peak temperature. Further non-limiting examples of embodiments of microwave systems and apparatuses that may be used and configured as described above can be found, for example, at FIGS. 3-7C and pp. 8-13 of U.S. Provisional App. No. 60/912,899; and FIGS. 3-9 and 20-26 and pp. 34-48 and FIGS. 20-26 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described, for example, in FIGS. 3A-7C and pp. 16-20 of Appendix 1 and FIGS. 20-26 and pp. 38-46 of Appendix 2. 
       FIG. 2  illustrates one embodiment of a system for generating and controlling microwave energy according to one embodiment of the invention. In the embodiment illustrated in  FIG. 2 , controller  302  may be, for example, a custom digital logic timer controller module that controls the delivery of microwave energy generated by signal generator  304  and amplified by amplifier  306 . Controller  302  may also control a solenoid valve to control application of vacuum from the vacuum source  308 . In one embodiment of the invention, signal generator  304  may be, for example, a Model N5181A MXG Analog Signal Generator 100 KHz-6 GHz, available from Agilent Technologies. In one embodiment of the invention, amplifier  306  may be, for example, a Model HD18288SP High Power TWT Amplifier 5.7-18 GHz, available from HD Communications Corporation. In one embodiment of the invention, vacuum source  308  may be, for example, a Model 0371224 Basic 30 Portable Vacuum Pump, available from Medela. In one embodiment of the invention, coolant source  310  may be, for example, a OP9TNAN001 NanoTherm Industrial Recirculating Chiller available from ThermoTek, Inc. 
       FIG. 3  illustrates a system for delivering microwave energy according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 3 , power is supplied by power source  318 , which may be, for example an AC mains power line. In the embodiment of the invention illustrated in  FIG. 3 , isolation transformer  316  isolates the mains power provided by power source  318  and supplies isolated power to controller  302 , vacuum source  308 , signal generator  304 , amplifier  306 , temperature data acquisition system  314  and coolant source  310 . In one embodiment of the invention, vacuum cable  372  connects vacuum source  308  to applicator  320 . In the embodiment of the invention illustrated in  FIG. 3 , signal generator  304  generates a signal, which may be, for example, a continuous wave (CW) signal having a frequency in the range of, for example, 5.8 GHz and that signal is supplied to amplifier  306 , which is controlled by controller  302 . In the embodiment of the invention illustrated in  FIG. 3 , an output signal from amplifier  306  may be transmitted to an applicator  320  by signal cable  322 . In one embodiment of the invention, signal cable  322  may be, for example, a fiber optic link. In one embodiment of the invention, applicator  320  may be, for example, a microwave energy device. In the embodiment of the invention illustrated in  FIG. 3 , coolant source  310  may supply a coolant, such as, for example, chilled de-ionized water, to applicator  320  through coolant tubing  324 , and, more particularly, coolant may be supplied to applicator  320  through inflow tubing  326  and returned to coolant source  310  through outflow tubing  328 . In the embodiment of the invention illustrated in  FIG. 3 , applicator  320  includes temperature measurement devices which relay temperature signals  330  to the temperature data acquisition system  314 , which, in turn, relays temperature signals by a fiber optic link  332  to the temperature display computer  312 . In one embodiment of the invention, isolation transformer  316  may be ISB-100W Isobox, available from Toroid Corporation of Maryland. In one embodiment of the invention, temperature display computer  312  may be, for example, a custom timer controller developed from a number of off-the-shelf timer relay components and custom control circuitry. In one embodiment of the invention, temperature data acquisition system  314  may be, for example, a Thermes-USB Temperature Data Acquisition System with OPT-1 Optical Link available from Physitemp Instruments Inc. 
       FIG. 4  is a side perspective view of a microwave applicator according to one embodiment of the invention.  FIG. 5  is a top perspective view of a microwave applicator according to one embodiment of the invention.  FIG. 6  is a front view of a microwave applicator according to one embodiment of the invention. In the embodiments of the invention illustrated in  FIGS. 4 through 6 , applicator  320  includes applicator cable  334 , applicator handle  344 , applicator head  346  and tissue head  362 . In the embodiment of the invention illustrated in  FIGS. 4 through 6 , tissue head  362  includes vacuum ports  342 , cooling plate  340 , tissue chamber  338  and tissue interface  336 . In one embodiment of the invention, tissue head  362  may be referred to as a tissue acquisition head. In the embodiment of the invention illustrated in  FIG. 5 , tissue head  362  includes alignment guide  348 , which includes alignment features  352 . In the embodiment of the invention illustrated in  FIG. 6 , tissue head  362  is mounted on applicator head  346  of applicator  320 . In the embodiment of the invention illustrated in  FIG. 6 , tissue head  362  includes alignment guide  348 , alignment features  352  and tissue chamber  338 . In the embodiment of the invention illustrated in  FIG. 6 , tissue chamber  338  includes tissue wall  354  and tissue interface  336 . In the embodiment of the invention illustrated in  FIG. 6 , tissue interface  336  includes cooling plate  340 , vacuum ports  342  and vacuum channel  350 . 
       FIG. 7  is a front view of a tissue head for use with a microwave applicator according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 7 , tissue head  362  includes alignment guide  348 , alignment features  352  and tissue chamber  338 . In the embodiment of the invention illustrated in  FIG. 7 , tissue chamber  338  includes tissue wall  354  and tissue interface  336 . In the embodiment of the invention illustrated in  FIG. 7 , tissue interface  336  includes cooling plate  340 , vacuum ports  342  and vacuum channel  350 . In one embodiment of the invention, tissue head  362  is detachable and may be used as a disposable element of a microwave applicator such as, for example, applicator  320 . 
       FIG. 8  is a cut away view of a tissue head according to one embodiment of the invention.  FIG. 8  is a cutaway view of a tissue head  362  and antenna  358  according to one embodiment of the invention. In one embodiment of the invention, antenna  358  may be, for example, a waveguide  364  which may include, for example, waveguide tubing  366  and dielectric filler  368 . In the embodiment of the invention illustrated in  FIG. 8  antenna  358  is isolated from cooling fluid  361  in coolant chamber  360  by standoff  376 . In the embodiment of the invention illustrated in  FIG. 8 , chamber wall  354  has a chamber angle Z which facilitates the acquisition of tissue. In the embodiment of the invention illustrated in  FIG. 8  tissue interface  336 , which may include cooling plate  340 , has a minimum dimension X and tissue chamber  338  has a depth Y. 
       FIG. 9  is a side cutaway view of a microwave applicator according to one embodiment of the invention.  FIG. 10  is a top perspective partial cutaway view of a microwave applicator according to one embodiment of the invention.  FIG. 11  is a side partial cutaway view of a microwave applicator according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIGS. 9 through 11 , applicator  320  includes applicator housing  356  and tissue head  362 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , applicator housing  356  encloses applicator handle  344  and at least a portion of applicator head  346 . In the embodiment of the invention illustrated in  FIGS. 9 through 11  applicator cable  334  includes coolant tubing  324 , inflow tubing  326 , outflow tubing  328 , signal cable  322  and vacuum cable  372 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , vacuum cable  372  is connected to vacuum splitter  374 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , applicator  320  includes antenna  358 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , antenna  358  may include waveguide antenna  364 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , waveguide antenna  364  may include dielectric filler  368  and waveguide tubing  366 . In embodiments of the invention, cooling chamber  360  may be configured to facilitate the continuous flow of cooling fluid  361  across one surface of cooling plate  340 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , signal cable  322  is connected to antenna  358  by antenna feed  370 , which may be, for example a distal end of a semi-rigid coaxial cable or a panel mount connector and includes the center conductor of the cable or connector. In the embodiment of the invention illustrated in  FIGS. 9 through 11 , applicator  320  includes tissue head  362 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , tissue head  362  includes tissue chamber  338 , chamber wall  354 , cooling plate  340  and cooling chamber  360 . In the embodiment of the invention illustrated in  FIGS. 9 through 11 , cooling chamber  360  is connected to inflow tubing  326  and outflow tubing  328 . In the embodiment of the invention illustrated in  FIG. 10 , vacuum cable  372  is connected to secondary vacuum cables  375 . In the embodiment of the invention illustrated in  FIG. 10 , secondary vacuum cables  375  may be connected to vacuum ports  342  (not shown) in tissue head  362 . 
     In the embodiment of the invention illustrated in  FIG. 11 , vacuum cable  372  is connected to secondary vacuum cables  375 . In the embodiment of the invention illustrated in  FIG. 11 , secondary vacuum cables  375  may be connected to vacuum ports  342  (not shown) in tissue head  362 . 
       FIGS. 12 and 13  are cutaway views of a tissue head and antenna according to one embodiment of the invention.  FIGS. 14 through 18  are cutaway views of a tissue head, antenna and field spreader according to one embodiment of the invention.  FIG. 19  is a cutaway view of a tissue head, antenna and field spreader with tissue engaged according to one embodiment of the invention. In the embodiments of the invention illustrated in  FIGS. 12 through 19  antenna  358  may be, for example, a waveguide antenna  364 . In the embodiments of the invention illustrated in  FIGS. 12 through 19  waveguide antenna  364  may comprise, for example, waveguide tubing  366  and waveguide filler  368  and may be connected to signal cable  322  by, for example, antenna feed  370 . In the embodiments of the invention illustrated in  FIGS. 12 through 19  tissue head  362  may comprise, for example, tissue chamber  338 , chamber wall  354 , cooling plate  340  and cooling chamber  360 . In the embodiments of the invention illustrated in  FIGS. 12 through 19  cooling chamber  360  may include cooling fluid  361 . 
     In the embodiment of the invention illustrated in  FIG. 12  antenna  358  is isolated from cooling fluid  361  in coolant chamber  360  by standoff  376 . In the embodiment of the invention illustrated in  FIG. 13  at least a portion of antenna  358  is positioned in coolant chamber  360 . In the embodiment of the invention illustrated in  FIG. 13  at least a portion of waveguide antenna  364  is positioned in coolant chamber  360 . In the embodiment of the invention illustrated in  FIG. 13  waveguide antenna  364  is positioned in coolant chamber  360  such that at least a portion of waveguide tubing  366  and dielectric filler  368  contact cooling fluid  361  in coolant chamber  360 . 
     In one embodiment of the invention illustrated in  FIG. 14  field spreader  378  is positioned at an output of waveguide antenna  364 . In one embodiment of the invention illustrated in  FIG. 14  field spreader  378  is an extension of dielectric filler  368  and is positioned at an output of waveguide antenna  364 . In one embodiment of the invention illustrated in  FIG. 14  field spreader  378  is an extension of dielectric filler  368  extending into coolant chamber  360 . In one embodiment of the invention illustrated in  FIG. 14  field spreader  378  is an extension of dielectric filler  368  extending through coolant chamber  360  to cooling plate  340 . 
     In one embodiment of the invention illustrated in  FIG. 15  field spreader  380  is integrated into dielectric filler  368  of waveguide antenna  364 . In one embodiment of the invention illustrated in  FIG. 15  field spreader  380  is a region of dielectric filler  368  having a dielectric constant which differs from the dielectric constant of the remainder of dielectric filler  368 . In one embodiment of the invention illustrated in  FIG. 15  field spreader  380  is a region having a dielectric constant which is in the range of approximately 1 to 15. 
     In one embodiment of the invention illustrated in  FIG. 16  field spreader  382  is integrated into dielectric filler  368  of waveguide antenna  364  and extends into coolant chamber  360 . In one embodiment of the invention illustrated in  FIG. 16  field spreader  382  is integrated into dielectric filler  368  of waveguide antenna  364  and extends through coolant chamber  360  to cooling plate  340 . In one embodiment of the invention illustrated in  FIG. 16  field spreader  382  has a dielectric constant which differs from the dielectric constant of dielectric filler  368 . In one embodiment of the invention illustrated in  FIG. 15  field spreader  380  is a region having a dielectric constant which is in the range of approximately 1 to 15. In one embodiment of the invention illustrated in  FIG. 17 , a field spreader may be comprised of a notch  384  in dielectric filler  368 . In one embodiment of the invention illustrated in  FIG. 17 , notch  384  is a cone shaped notch in dielectric filler  368 . In one embodiment of the invention illustrated in  FIG. 17 , notch  384  is connected to cooling chamber  360  such that cooling fluid  361  in cooling chamber  360  at least partially fills notch  384 . In one embodiment of the invention illustrated in  FIG. 17 , notch  384  is connected to cooling chamber  360  such that cooling fluid  361  in cooling chamber  360  fills notch  384 . 
     In one embodiment of the invention illustrated in  FIG. 18  field spreader  382  is integrated into or protrudes from cooling plate  340 . In one embodiment of the invention illustrated in  FIG. 18  field spreader  382  is integrated into or protrudes from cooling plate  340  at tissue interface  336 . In one embodiment of the invention illustrated in  FIG. 18  field spreader  382  is integrated into or protrudes from cooling plate  340  into tissue chamber  338 . In one embodiment of the invention illustrated in  FIG. 18  field spreader  382  may form at least a portion of tissue interface  336 . 
     In the embodiment of the invention illustrated in  FIG. 19  skin  1307  is engaged in tissue chamber  338 . In the embodiment of the invention illustrated in  FIG. 19  dermis  1305  and hypodermis  1303  are engaged in tissue chamber  338 . In the embodiment of the invention illustrated in  FIG. 19 , skin surface  1306  is engaged in tissue chamber  338  such that skin surface  1306  is in contact with at least a portion of chamber wall  354  and cooling plate  340 . In the embodiment of the invention illustrated in  FIG. 19 , skin surface  1306  is engaged in tissue chamber  338  such that skin surface  1306  is in contact with at least a portion of tissue interface  336 . As illustrated in  FIG. 19 , a vacuum pressure may be used to elevate dermis  1305  and hypodermis  1303 , separating dermis  1305  and hypodermis  1303  from muscle  1301 . As illustrated in  FIG. 19 , a vacuum pressure may be used to elevate dermis  1305  and hypodermis  1303 , separating dermis  1305  and hypodermis  1303  from muscle  1301  to, for example, protect muscle  1301  by limiting or eliminating the electromagnetic energy which reaches muscle  1301 . 
       FIG. 20  is a cutaway view of a tissue head and antenna with tissue engaged according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 20  applicator  320  includes applicator housing  356 , antenna  358 , vacuum channels  350  and tissue head  362 . In the embodiment of the invention illustrated in  FIG. 20  tissue head  362  includes vacuum conduit  373 , cooling elements  386  and cooling plate  340 . In embodiments of the invention, cooling elements  386  may be, for example: solid coolants; heat sinks; liquid spray, gaseous spray, cooling plates, thermo-electric coolers; or and combinations thereof. In the embodiment of the invention illustrated in  FIG. 20  vacuum channels  350  are connected to vacuum conduit  373  and vacuum port  342 . In the embodiment of the invention illustrated in  FIG. 20  skin surface  1306  is engaged in tissue chamber  338  by, for example a vacuum pressure at vacuum ports  342 , such that skin surface  1306  is in contact with at least a portion of chamber wall  354  and cooling plate  340 . In the embodiment of the invention illustrated in  FIG. 20  skin surface  1306  is engaged in tissue chamber  338  by, for example a vacuum pressure at vacuum ports  342 , such that skin surface  1306  is in contact with at least a portion of tissue interface  336 . As illustrated in  FIG. 20 , a vacuum pressure at vacuum ports  342  may be used to elevate dermis  1305  and hypodermis  1303 , separating dermis  1305  and hypodermis  1303  from muscle  1301 . As illustrated in  FIG. 20 , a vacuum pressure at vacuum ports  342  may be used to elevate dermis  1305  and hypodermis  1303 , separating dermis  1305  and hypodermis  1303  from muscle  1301  to, for example, protect muscle  1301  by limiting or eliminating the electromagnetic energy which reaches muscle  1301 . 
       FIGS. 21 through 23  illustrate tissue heads including a plurality of waveguide antennas according to one embodiment of the invention. In the embodiments of the invention illustrated in  FIGS. 21 through 23  a tissue head  362  includes a plurality of waveguide antennas  364  according to embodiments of the invention. In the embodiment of the invention illustrated in  FIG. 21 , two waveguide antennas  364  are positioned in tissue head  362 . In the embodiment of the invention illustrated in  FIG. 22 , four waveguide antennas  364  are positioned in tissue head  362 . In the embodiment of the invention illustrated in  FIG. 23 , six waveguide antennas  364  are positioned in tissue head  362 . In the embodiment of the invention illustrated in  FIGS. 21 through 23  waveguides  364  include feed connectors  388  and tuning screws  390 . 
       FIG. 24  illustrates a disposable tissue head  363  for use with an applicator  320  according to one embodiment of the invention. In embodiments of the invention disposable tissue head  363  may have all of the elements of tissue head  362 . In embodiments of the invention disposable tissue head  363  may include elements of tissue head  362 , such as, for example, tissue interface  336 , cooling plate  340 , tissue chamber  338 , or vacuum ports  342 . In embodiments of the invention disposable tissue head  363  may include a cooling chamber  360 . In embodiments of the invention disposable tissue head  363  may include a standoff  376 . In the embodiment of the invention illustrated in  FIG. 24  disposable tissue head  363  engages with applicator housing  356 , positioning antennas  364  in disposable tissue head  363 .  FIG. 25  illustrates a disposable tissue head  363  for use with an applicator  320  according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 25  disposable tissue head  363  engages with applicator housing  356  and is held in place with latches  365 . 
     Tissue Profiles 
       FIGS. 26 through 51  illustrate a series of profiles, including, for example, profiles of power deposition, profiles of power loss density, profiles of specific absorption rates or profiles of tissue temperature, according to embodiments of the invention. In embodiments of the present invention, profiles such as for example, profiles of power deposition, profiles of power loss density, profiles of specific absorption rates or profiles of tissue temperature may be referred to as tissue profiles. In the embodiments of the invention illustrated in  FIGS. 26 through 51  the illustrated tissue profiles may be representative of, for example, SAR profiles, power loss density profiles or temperature profiles. In some embodiments of the invention, the embodiments and components of embodiments of systems illustrated in  FIGS. 2 through 25  as well as, e.g., those illustrated and described at FIGS. 3-7C and pp. 8-13 of U.S. Provisional App. No. 60/912,899; and FIGS. 3-9 and 20-26 and pp. 34-48 and FIGS. 20-26 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described in, e.g., FIGS. 3A-7C and pp. 16-20 of Appendix 1 and FIGS. 20-26 and pp. 38-46 of Appendix 2 may be used to generate the tissue profiles illustrated in  FIGS. 26 through 51 . 
       FIGS. 26 through 35  illustrate a series of tissue profiles according to embodiments of the invention. In embodiments of the invention illustrated in  FIGS. 26 through 35  antenna  358  may be, for example, a simple dipole antenna or a waveguide antenna. In embodiments of the invention illustrated in  FIGS. 26 through 35  antenna  358  may be positioned in a medium  1318 . In embodiments of the invention illustrated in  FIGS. 26 through 35  antenna  358  radiates an electromagnetic signal through medium  1318  and into tissue, generating the patterns illustrated in  FIGS. 26 through 35 . In one embodiment of the invention, medium  1318  may be, for example, a dielectric material having a dielectric constant (which may also be referred to as permittivity) of approximately 10. 
     In the embodiment of the invention illustrated in  FIG. 26  antenna  358  may radiate energy at a frequency of, for example, approximately 3.0 GHz. In the embodiment of the invention illustrated in  FIG. 27  antenna  358  may radiate energy at a frequency of, for example, approximately 3.5 GHz. In the embodiment of the invention illustrated in  FIG. 28  antenna  358  may radiate energy at a frequency of, for example, approximately 4.0 GHz. In the embodiment of the invention illustrated in  FIG. 29  antenna  358  may radiate energy at a frequency of, for example, approximately 4.5 GHz. In the embodiment of the invention illustrated in  FIG. 30  antenna  358  may radiate energy at a frequency of, for example, approximately 5.0 GHz. In the embodiment of the invention illustrated in  FIG. 31  antenna  358  may radiate energy at a frequency of, for example, approximately 5.8 GHz. In the embodiment of the invention illustrated in  FIG. 32  antenna  358  may radiate energy at a frequency of, for example, approximately 6.5 GHz. In the embodiment of the invention illustrated in  FIG. 33  antenna  358  may radiate energy at a frequency of, for example, approximately 7.5 GHz. In the embodiment of the invention illustrated in  FIG. 34  antenna  358  may radiate energy at a frequency of, for example, approximately 8.5 GHz. In the embodiment of the invention illustrated in  FIG. 35  antenna  358  may radiate energy at a frequency of, for example, approximately 9.0 GHz. In one embodiment of the invention, a tissue profile, such as the profile illustrated in  FIGS. 34 and 35  may include at least two constructive interference peaks, where in a first constructive interference peak is positioned in tissue below a second constructive interference peak. In one embodiment of the invention, a tissue profile, such as the profile illustrated in  FIGS. 34 and 35  may include at least two constructive interference peaks, where in a second constructive interference peak is positioned near a skin surface. 
     In embodiments of the invention, wherein antenna  358  is representative of a wave guide antenna such as, for example, the waveguide antenna illustrated in  FIG. 48  radiating through, for example, at least a portion of a tissue head including a tissue interface, the frequencies at which particular tissue profiles, such as, for example, SAR profiles, power loss profiles or temperature profiles are created may vary from the frequencies at which that such profiles are generated by a dipole antenna. In one embodiment of the invention, a tissue head positioned between a waveguide antenna and a skin surface may comprise, for example, for example, a standoff  376 , a cooling chamber  360  filled with cooling fluid  361 , such as, for example de-ionized water and a cooling plate  340 . In one embodiment of the invention, wherein antenna  358  is a waveguide, antenna  358  may be positioned a distance of approximately 1.5 millimeters from skin surface  1306 . In one embodiment of the invention,  FIG. 34  illustrates a resulting profile where antenna  358  is a waveguide antenna radiating energy through a tissue head at a frequency of, for example, approximately 10 GHz. In one embodiment of the invention,  FIG. 35  illustrates a resulting profile where antenna  358  is a waveguide antenna radiating energy through a tissue head at a frequency of, for example, approximately 12 GHz. 
     In embodiments of the invention illustrated in  FIGS. 26 through 35 , antenna  358  may be a dipole antenna and may have a length of, for example, approximately one half wavelength (measured at the operational frequency). In embodiments of the invention illustrated in  FIGS. 26 through 35 , antenna  358  may be positioned in, for example, a radiating near field region with respect to skin surface  1306 . In embodiments of the invention illustrated in  FIGS. 26 through 35  antenna  358  may be positioned at a distance of, for example, approximately 10 millimeters from skin surface  1306 . In embodiments of the invention illustrated in  FIGS. 26 through 30  antenna  358  may be a dipole antenna having an antenna height of, for example, approximately 12 millimeters. In one embodiment of the invention illustrated in  FIG. 31  antenna  358  may be a dipole antenna having an antenna height of, for example, approximately 8.5 millimeters. In embodiments of the invention illustrated in  FIGS. 32 through 35  antenna  358  may be a dipole antenna having an antenna height of, for example, approximately 7 millimeters. 
     In embodiments of the invention illustrated in  FIGS. 26 through 35  power from antenna  358  is transmitted through skin surface  1306 , generating a profile, such as, for example, a SAR profile, a power loss density profile or a temperature profile, in, for example, dermis  1305 . In embodiments of the invention illustrated in  FIGS. 26 through 35  power transmitted from antenna  358  though skin surface  1306  generates a profile having a peak in first tissue region  1309 . In embodiments of the invention illustrated in  FIGS. 26 through 35  power transmitted from antenna  358  though skin surface  1306  generates a profile wherein the magnitude decreases from first tissue region  1309  to second tissue region  1311 . In embodiments of the invention illustrated in  FIGS. 26 through 35  power transmitted from antenna  358  though skin surface  1306  generates a profile wherein the magnitude decreases from second tissue region  1311  to third tissue region  1313 . In embodiments of the invention illustrated in  FIGS. 26 through 35  power transmitted from antenna  358  though skin surface  1306  generates a profile wherein the magnitude decreases from third tissue region  1313  to fourth tissue region  1315 . 
     In one embodiment of the invention, illustrated in, for example,  FIGS. 26 through 39 , power transmitted from antenna  358  through skin surface  1306  is at least partially reflected off of interface  1308  such that a peak magnitude of, for example, SAR, power loss density or temperature, is generated in first tissue region  1309  below skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 26 through 39 , interface  1308  may be idealized as a substantially straight line for the purpose of simplified illustration, however, in actual tissue, interface  1308  may be expected to be a non-linear, non-continuous, rough interface which may also include tissue structures and groups of tissue structures which cross and interrupt interface  1308 . In one embodiment of the invention, a peak magnitude of, for example, SAR, power loss density or temperature is formed as a result of constructive interference between incident and reflected power. In one embodiment of the invention, a peak magnitude of, for example, SAR, power loss density or temperature formed as a result of constructive interference between incident and reflected power is positioned at first tissue region  1309  below a first layer of dermal tissue. In one embodiment of the invention, a minimum magnitude of, for example, SAR, power loss density or temperature is formed as a result of destructive interference between incident and reflected power. In one embodiment of the invention, a minimum magnitude of, for example, SAR, power loss density or temperature formed as a result of destructive interference between incident and reflected power is positioned in a first layer of dermal tissue near skin surface  1306 . In one embodiment of the invention, interface  1308  may be, for example, an interface between dermis  1305  and hypodermis  1303 . In one embodiment of the invention, first tissue region  1309  may be formed in the lower half of the dermis. In one embodiment of the invention, interface  1308  may be, for example, an interface between a high dielectric, high conductivity tissue layer and a low dielectric, low conductivity tissue layer. In one embodiment of the invention, interface  1308  may be, for example, an interface between a high dielectric, high conductivity tissue layer and a low dielectric tissue layer. In one embodiment of the invention, interface  1308  may be, for example, an interface between a glandular layer and a layer of the hypodermis. 
     In one embodiment of the invention, energy transmitted through skin surface  1306  creates a peak temperature in first region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises a temperature in first region  1309  to a temperature sufficient to induce hyperthermia in tissue in region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises a temperature in first region  1309  to a temperature sufficient to ablate tissue in region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises a temperature in first region  1309  to a temperature sufficient to cause cell death in tissue in region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises a temperature in first region  1309  to a temperature sufficient to form a lesion core in first region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises a temperature in first region  1309  to a temperature sufficient to create a lesion in tissue in region  1309 . In one embodiment of the invention, energy transmitted through skin surface  1306  raises the temperature of tissue in region  1309  by dielectric heating. In one embodiment of the invention, energy transmitted through skin surface  1306  preferentially raises the temperature of tissue in region  1309  above the temperature of surrounding regions. In one embodiment of the invention, energy transmitted through skin surface  1306  preferentially raises the temperature of tissue in region  1309  above the temperature of surrounding regions to a temperature sufficient to cause secondary effects, such as, for example the destruction of bacteria in such surrounding regions. 
     In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to heat tissue around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to heat tissue structures, such as, for example, sweat glands or hair follicles, in tissue around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to cause hyperthermia in tissue around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to ablate tissue around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to kill bacteria in tissue or tissue structures around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to create a lesion in tissue around first region  1309 , by, for example, thermal conductive heating. In one embodiment of the invention, energy transmitted through skin surface  1306  generates a temperature in first region  1309  sufficient to expand a lesion into tissue around first region  1309 , by, for example, thermal conductive heating. 
     Near Field 
       FIGS. 36 through 39  illustrate a series of tissue profiles according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIGS. 36 through 39  antenna  358  may be, for example, a simple dipole antenna or a waveguide antenna. In the embodiment of the invention illustrated in  FIG. 36 through 39  antenna  358  may be excited at a predetermined frequencies such as, for example, approximately 5.8 GHz. In embodiments of the invention illustrated in  FIGS. 36 through 38 , antenna  358  may be positioned in, for example, a radiating near field region with respect to skin surface  1306 . In an embodiment of the invention illustrated in  FIG. 39 , antenna  358  may be positioned in, for example, a reactive near field region with respect to skin surface  1306 . In embodiments of the invention illustrated in  FIGS. 36 through 39  antenna  358  may be positioned at a distance A of, for example, between approximately 10 millimeters and approximately 2 millimeters from skin surface  1306 . In embodiments of the invention illustrated in  FIGS. 36 through 39  antenna  358  may be positioned in a medium  1318 . In embodiments of the invention illustrated in  FIGS. 36 through 39  antenna  358  may be a dipole antenna having an antenna height of approximately 8.5 millimeters. In the embodiments of the invention illustrated in  FIGS. 36 through 39  antenna  358  may radiate energy at a frequency of, for example, approximately 5.8 GHz. 
     In embodiments of the invention illustrated in  FIGS. 36 through 39  power from antenna  358  is transmitted through skin surface  1306 , generating a tissue profile in dermis  1305 . In embodiments of the invention illustrated in  FIGS. 36 through 39  power transmitted from antenna  358  though skin surface  1306  generates a tissue profile having a peak in first tissue region  1309 . In embodiments of the invention illustrated in  FIGS. 36 through 39  power transmitted from antenna  358  though skin surface  1306  generates a tissue profile which may represent, for example, SAR, power loss density or temperature. In embodiments of the invention illustrated in  FIGS. 36 through 39  power transmitted from antenna  358  though skin surface  1306  generates a tissue profile wherein the magnitude of, for example, SAR, power loss density or temperature, decreases from first tissue region  1309  to second tissue region  1311 , from second tissue region  1311  to third tissue region  1313  and from third tissue region  1313  to fourth tissue region  1315 . 
     In one embodiment of the invention, illustrated in, for example,  FIG. 36 , power transmitted from antenna  358  through skin surface  1306  is at least partially reflected off of interface  1308  such that a peak of, for example, SAR, power loss density or temperature, is generated in first tissue region  1309  below skin surface  1306 . In one embodiment of the invention illustrated in, for example,  FIG. 36 , a peak of, for example, SAR, power loss density or temperature formed as a result of constructive interference between incident and reflected power is positioned at first tissue region  1309  below a first layer of dermal tissue. In one embodiment of the invention illustrated in, for example,  FIG. 36 , a peak of, for example, SAR, power loss density or temperature formed as a result of constructive interference between incident and reflected power is positioned at first tissue region  1309  in a lower half of dermis  1305 . In one embodiment of the invention illustrated in  FIG. 36  antenna  358  may be positioned at a distance A of, for example, approximately 10 millimeters from skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 37  antenna  358  may be positioned at a distance A of, for example, approximately 5 millimeters from skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 38  antenna  358  may be positioned at a distance A of, for example, approximately 3 millimeters from skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 39  antenna  358  may be positioned at a distance A of, for example, approximately 2 millimeters from skin surface  1306 . In one embodiment of the invention illustrated in  FIGS. 36 through 38 , tissue in region  1309  is preferentially heated with respect to tissue in layers above first tissue region  1309 . 
     In one embodiment of the invention illustrated in  FIG. 36  antenna  358  may be positioned at a distance A within a radiating near field of skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 37  antenna  358  may be positioned at a distance A within a radiating near field of skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 38  antenna  358  may be positioned at a distance A within a radiating near field of skin surface  1306 . In one embodiment of the invention illustrated in  FIG. 39  antenna  358  may be positioned at a distance A within a reactive near field of skin surface  1306 . As illustrated in  FIG. 39 , in one embodiment of the invention, positioning an antenna in a reactive near field results in substantial reactive coupling, which increases power deposition at the upper skin layer and destroys the preferential heating profiles illustrated in  FIGS. 36  thorough  38 . In one embodiment of the invention, a reactive near field may be that distance which results in substantial reactive coupling between an antenna and adjacent tissue, increasing power deposition at the upper skin layer and destroying the preferential heating profiles illustrated in  FIGS. 36  thorough  38   
     Preferential Heating—Dermis 
       FIGS. 40 through 43  illustrate tissue profiles according to one embodiment of the invention. In embodiments of the invention illustrated in  FIGS. 40 through 43  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, sweat glands, including, for example, eccrine glands, apocrine glands or apoeccrine glands. In embodiments of the invention illustrated in  FIGS. 40 through 43  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, sweat glands, including, for example, eccrine glands, apocrine glands or apoeccrine glands. In embodiments of the invention illustrated in  FIGS. 40 through 43  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, hair follicles. In embodiments of the invention illustrated in  FIGS. 40 through 43  tissue structures  1325  may include ducts  1329  extending from tissue structures  1325  to skin surface  1306 . In embodiments of the invention, tissue structures  1325  include groups of tissue structures  1325 . 
       FIG. 40  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 40  a lesion core  1321  is created in a predetermined portion of dermis  1305  by, for example, irradiating dermis  1305  with electromagnetic radiation to generate dielectric heating in tissue at lesion core  1321 . In one embodiment of the invention, lesion core  1321  may be, for example, a point or region within a tissue layer where a lesion starts to grow. In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  is created by heat generated in dermal tissue by dielectric heating of lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  expands as energy is added to dermis  1305 . In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  may be located in a region of dermis  1305  where a constructive interference peak is generated by electromagnetic energy transmitted through skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  may be located in a region of dermis  1305  where a constructive interference peak is generated by electromagnetic energy transmitted through skin surface  1306  wherein at least a portion of the electromagnetic energy transmitted through skin surface  1306  reflects off of interface  1308  which may be, for example, an interface between high dielectric, high conductivity tissue and low dielectric, low conductivity tissue. In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  may be located in a region of dermis  1305  where a constructive interference peak is generated by electromagnetic energy transmitted through skin surface  1306  wherein at least a portion of the electromagnetic energy transmitted through skin surface  1306  reflects off of interface  1308  which may be, for example, an interface between high dielectric, high conductivity tissue and low dielectric tissue. In the embodiment of the invention illustrated in  FIG. 40  interface  1308  may be idealized as a substantially straight line for the purpose of simplified illustration, however, in actual tissue, interface  1308  may be a non-linear, non-continuous, rough interface which may also include many tissue structures and groups of tissue structures which cross and interrupt the tissue interface. In the embodiment of the invention illustrated in  FIG. 40  lesion core  1321  may be located in a region of dermis  1305  where a constructive interference peak is generated by electromagnetic energy transmitted through skin surface  1306  wherein at least a portion of the electromagnetic energy transmitted through skin surface  1306  reflects off of interface  1308  which may be, for example, an interface between dermis  1305  and hypodermis  1303 . 
       FIG. 41  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 41  lesion core  1321  expands as energy is added to dermis  1305 , generating heat which is conducted into surrounding tissue creating expanded lesion  1323 . In the embodiment of the invention illustrated in  FIG. 41  heat conducted from lesion core  1321  into expanded lesion  1323  damages tissue, including tissue structures  1325  outside lesion  1321 . In the embodiment of the invention illustrated in  FIG. 41  heat conducted from lesion core  1321  into expanded lesion  1323  crosses interface  1308  and damages tissue below interface  1308 , including tissue structures  1325  outside and below lesion core  1321 . 
       FIG. 42  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 42  a lesion core  1321  is created in a predetermined portion of dermis  1305  by, for example, irradiating dermis  1305  with electromagnetic radiation to generate dielectric heating in tissue at lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 42  lesion core  1321  expands as energy is added to dermis  1305 . In the embodiment of the invention illustrated in  FIG. 42  heat is removed from skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 42  heat is removed from dermis  1305  through skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 42  heat is removed from dermis  1305  through skin surface  1306  by cooling skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 42  heat removed from dermis  1305  through skin surface  1306  prevents lesion core  1321  and expanded lesion  1323  from growing in the direction of skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 42  removed from dermis  1305  through skin surface  1306  prevents lesion core  1321  and expanded lesion  1323  from growing into cooled region  1327 . 
       FIG. 43  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 43  a lesion core  1321  is created in a predetermined portion of dermis  1305  by, for example, irradiating dermis  1305  with electromagnetic radiation to generate dielectric heating in tissue at lesion core  1321  and expanded lesion  1323  is created by heat conducted from lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 43  lesion core  1321  expands as energy is added to dermis  1305  and expanded lesion  1323  expands as heat is conducted from lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 43  heat is removed from skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 43  heat is removed from dermis  1305  through skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 43  heat is removed from dermis  1305  through skin surface  1306  by cooling skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 43  heat removed from dermis  1305  through skin surface  1306  prevents lesion core  1321  and expanded lesion  1323  from growing in the direction of skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 43  removed from dermis  1305  through skin surface  1306  prevents lesion core  1321  and expanded lesion  1323  from growing into cooled region  1327 . 
     Preferential Heating—Glandular Layer 
       FIGS. 44 through 47  illustrate tissue profiles according to embodiments of the invention. In embodiments of the invention illustrated in  FIGS. 44 through 47  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, sweat glands, including, for example, eccrine glands, apocrine glands or apoeccrine glands. In embodiments of the invention illustrated in  FIGS. 44 through 47  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, sweat glands, including, for example, eccrine glands, apocrine glands or apoeccrine glands. In embodiments of the invention illustrated in  FIGS. 44 through 47  dermis  1305  and hypodermis  1303  may contain tissue structures  1325  which may be, for example, hair follicles. In embodiments of the invention illustrated in  FIGS. 44 through 47  tissue structures  1325  may include ducts  1329  extending from tissue structures  1325  to skin surface  1306 . In embodiments of the invention illustrated in  FIGS. 44 through 47  tissue structures  1325  may be concentrated in a glandular layer  1331 . In embodiments of the invention illustrated in  FIGS. 44 through 47  tissue structures  1325  may be concentrated in a glandular layer  1331  wherein glandular layer  1331  has an upper interface  1335  and a lower interface  1333 . In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may have an upper interface  1335  between glandular layer  1331  and dermis  1305 . In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may have a lower interface  1333  between glandular layer  1331  and hypodermis  1303 . In the embodiment of the invention illustrated in  FIGS. 44 through 47  interface  1333  may be, in actual tissue a non-linear, non-continuous, rough interface which may also include many tissue structures and groups of tissue structures and groups of tissue structures which add to the roughness and nonlinearity of tissue interface  1333 . 
     In embodiments of the invention illustrated in  FIGS. 44 through 47  tissue structures  1325  may be composed, at least in part of high dielectric/high conductivity tissue such as, for example, sweat glands. In embodiments of the invention illustrated in  FIGS. 44 through 47  tissue structures  1325  may be composed, at least in part of tissue having a high water content, such as, for example, sweat glands. In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may be composed, at least in part of high dielectric/high conductivity tissue. In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may have an upper interface  1335  between glandular layer  1331  and high dielectric/high conductivity tissue, such as, for example, dermis  1305 . In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may have a lower interface  1333  between glandular layer  1331  and low dielectric/low conductivity tissue, such as, for example, hypodermis  1303 . In embodiments of the invention illustrated in  FIGS. 44 through 47  glandular layer  1331  may have a lower interface  1333  between glandular layer  1331  and low dielectric tissue. 
       FIG. 44  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 44  a lesion core  1321  is created in a predetermined portion of glandular layer  1331  by, for example, irradiating glandular layer  1331  with electromagnetic radiation to generate dielectric heating in tissue at lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 44  lesion core  1321  is created by heat generated in glandular layer  1331  by dielectric heating of lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 44  lesion core  1321  expands as energy is added to glandular layer  1331 . In the embodiment of the invention illustrated in  FIG. 44  lesion core  1321  may be located in a region of glandular layer  1331  where a constructive interference peak of, for example, SAR, power loss density or temperature, is generated by electromagnetic energy transmitted through skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 44  lesion core  1321  may be located in a region of glandular layer  1331  where a constructive interference peak of, for example, SAR, power loss density or temperature, is generated by electromagnetic energy transmitted through skin surface  1306  wherein at least a portion of the electromagnetic energy transmitted through skin surface  1306  reflects off of lower interface  1333 . In the embodiment of the invention illustrated in  FIG. 44  lesion core  1321  may be located in a region of glandular layer  1331  where a constructive interference peak of, for example, SAR, power loss density or temperature, is generated by electromagnetic energy transmitted through skin surface  1306  wherein at least a portion of the electromagnetic energy transmitted through skin surface  1306  reflects off of lower interface  1333  which may be, for example, an interface between glandular layer  1331  and hypodermis  1303 . 
       FIG. 45  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIG. 45  lesion core  1321  expands as energy is added to glandular layer  1331 , generating heat which is conducted into surrounding tissue, creating expanded lesion  1323 . In the embodiment of the invention illustrated in  FIG. 45  heat conducted from lesion core  1321  into expanded lesion  1323  damages tissue, including tissue structures  1325  outside lesion core  1321 . In the embodiment of the invention illustrated in  FIG. 45  heat conducted from lesion core  1321  into expanded lesion  1323  crosses lower interface  1333  and damages tissue below lower interface  1333  and outside lesion core  1321 . 
       FIGS. 46 and 47  illustrate tissue profiles according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIGS. 46 and 47  a lesion core  1321  is created in a portion of glandular layer  1331  by, for example, irradiating glandular layer  1331  with electromagnetic radiation to generate dielectric heating in tissue at lesion core  1321 . In the embodiments of the invention illustrated in  FIGS. 46 and 47  lesion core  1321  expands as energy is added to glandular layer  1331  and expanded lesion  1323  is created by heat conducted from lesion core  1323 . In the embodiments of the invention illustrated in  FIGS. 46 and 47  heat is removed from skin surface  1306 . In the embodiments of the invention illustrated in  FIGS. 46 and 47  heat is removed from dermal layer  1305  through skin surface  1306 . In the embodiments of the invention illustrated in  FIGS. 46 and 47  heat is removed from dermal layer  1305  through skin surface  1306  by cooling skin surface  1306 , creating cooled region  1307  in dermis  1305 . In the embodiment of the invention illustrated in  FIG. 47  heat removed from dermal layer  1305  through skin surface  1306  prevents expanded lesion  1323  from growing in the direction of skin surface  1306 . In the embodiment of the invention illustrated in  FIG. 46  heat removed from glandular layer  1331  through skin surface  1306  prevents expanded lesion  1323  from growing into cooled region  1327 . 
       FIGS. 48 through 51  illustrate tissue profiles and apparatuses according to embodiments of the invention. In  FIGS. 48 through 51 , antenna  358  may be, for example, waveguide antenna  364 . In the embodiment of the invention illustrated in  FIGS. 48 and 49 , waveguide antenna  364  may include, for example, waveguide tubing  366  and dielectric filler  368 . In the embodiment of the invention illustrated in  FIGS. 48 and 49  electromagnetic energy may be radiated into dermis  1305  through a tissue head  362  which may include, for example, standoff  376 , coolant chamber  360  and cooling plate  340 . In the embodiment of the invention illustrated in  FIG. 48  a peak which may be, for example, a peak SAR, peak power loss density or peak temperature, is generated in first tissue region  1309 . In the embodiment of the invention illustrated in  FIG. 48  a reduced magnitude which may be, for example, a reduced SAR, reduced power loss density or reduced temperature, is generated in second tissue region  1311  with further reduced magnitudes in third tissue region  1313  and fourth tissue region  1315 . In the embodiment of the invention illustrated in  FIG. 48  dermis  1305  is separated from hypodermis  1303  by interface  1308 . In the embodiment of the invention illustrated in  FIG. 48  interface  1308  may be idealized as a substantially straight line for the purposes of simplified illustration, however, in actual tissue, interface  1308  may be a non-linear, non-continuous, rough interface which may also include many tissue structures and groups of tissue structures which cross and interrupt the tissue interface. In the embodiment of the invention illustrated in  FIG. 48  hypodermis  1303  lies over muscle tissue  1301 . In the embodiment of the invention illustrated in  FIG. 48  electromagnetic radiation may be radiated at a frequency of, for example, between 5 and 6.5 GHz. In the embodiment of the invention illustrated in  FIG. 48  electromagnetic radiation may be radiated at a frequency of, for example, approximately 5.8 GHz. In the embodiment of the invention illustrated in  FIG. 48  dermis  1305  may be assumed have a dielectric constant of, for example, approximately 38 and a conductivity of, for example, approximately 4.5 siemens per meter. In the embodiment of the invention illustrated in  FIG. 48  hypodermis  1303  may be assumed to have a dielectric constant of, for example, approximately 5 and a conductivity of, for example, approximately 0.31 siemens per meter. In the embodiment of the invention illustrated in  FIG. 48  muscle tissue  1301  may be assumed to have a dielectric constant of, for example, approximately 42 and a conductivity of, for example, approximately 5.2 siemens per meter. In the embodiment of the invention illustrated in  FIG. 48  standoff  376  may be, for example, polycarbonate and may have a dielectric constant of, for example, approximately 3.4 and a conductivity of, for example, approximately 0.0051 siemens per meter. In the embodiment of the invention illustrated in  FIG. 48  cooling plate  340  may be, for example, alumina (99.5%) and may have a dielectric constant of, for example, approximately 9.9 and a conductivity of, for example, approximately 3×10 −4  siemens per meter. In the embodiment of the invention illustrated in  FIG. 48  cooling fluid  361  may be, for example, de-ionized water and may have, for example, a dielectric constant of, for example, approximately 81 and a conductivity of, for example, approximately 0.0001 siemens per meter. 
     In the embodiment of the invention illustrated in  FIG. 49  a peak, which may be, for example, a peak SAR, peak power loss density or peak temperature, is generated in first tissue region  1309 . In the embodiment of the invention illustrated in  FIG. 48  a reduced magnitude which may be, for example, a reduced SAR, reduced power loss density or reduced temperature, is generated in second tissue region  1311  with further reduced magnitudes in third tissue region  1313  and fourth tissue region  1315 . In the embodiment of the invention illustrated in  FIG. 49  dermis  1305  is separated from hypodermis  1303  by interface  1308 . In the embodiment of the invention illustrated in  FIG. 49  interface  1308  may be modeled as a nonlinear interface, to more closely resemble an actual interface between dermal and hypodermal tissue. In the embodiment of the invention illustrated in  FIG. 49  hypodermis  1303  lies over muscle tissue  1301 . In the embodiment of the invention illustrated in  FIG. 49  electromagnetic radiation may be radiated at a frequency of, for example, 5.8 GHz. In the embodiment of the invention illustrated in  FIG. 49  dermis  1305  may be assumed to have a dielectric constant of, for example, 38.4 and a conductivity of, for example 4.54 siemens per meter. In the embodiment of the invention illustrated in  FIG. 49  hypodermis  1303  may be assumed to have, for example, a dielectric constant of, for example, 4.9 and a conductivity of, for example, 0.31 siemens per meter. In the embodiment of the invention illustrated in  FIG. 49  muscle tissue  1301  may be assumed to have, for example, a dielectric constant of, for example, 42.22 and a conductivity of, for example, 5.2 siemens per meter. In the embodiment of the invention illustrated in  FIG. 49  standoff  376  may be, for example, polycarbonate and may have, for example, a dielectric constant of, for example, 3.4 and a conductivity of, for example, 0.0051 siemens per meter. In the embodiment of the invention illustrated in  FIG. 49  cooling plate  340  may be, for example, alumina (99.5%) and may have, for example, a dielectric constant of, for example, 9.9 and a conductivity of, for example, 3×10 −4  siemens per meter. In the embodiment of the invention illustrated in  FIG. 49  cooling fluid  361  may be, for example, de-ionized water and may have, for example, a dielectric constant of, for example, 81 and a conductivity of, for example, 0.0001 siemens per meter. 
       FIG. 50  illustrates a tissue profile according to one embodiment of the invention.  FIG. 51  illustrates a tissue profile according to one embodiment of the invention. In the embodiment of the invention illustrated in  FIGS. 50 and 51 , antenna  358  may be, for example, a waveguide antenna  364 . In one embodiment of the invention, waveguide antenna  364  may have a dielectric filler  368 . In one embodiment of the invention, antenna  358  may be positioned on, for example, a tissue head  362  comprising, for example, standoff  376 , coolant chamber  360  and cooling plate  340 . In one embodiment of the invention, cooling chamber  340  may contain cooling fluid  361 , which may be, for example de-ionized water. In one embodiment of the invention, a tissue head  362  may include a tissue chamber (not shown) adapted to position tissue against tissue interface  336 . In one embodiment of the invention, antenna  358  is adapted to transmit electromagnetic radiation through skin surface  1306  creating a tissue profile which may be representative of, for example, a SAR profile, a power loss density profile or a temperature profile. In one embodiment of the invention, the tissue profile includes first tissue region  1309 , second tissue region  1311 , third tissue region  1313  and fourth tissue region  1315 . In one embodiment of the invention, first tissue region  1309  may represent, for example, a peak SAR, peak power loss density or peak temperature. In one embodiment of the invention, first tissue region  1309  may be located in, for example, dermis  1305 , near an interface  1308  between dermis  1305  and hypodermis  1303 , which overlies muscle  1301 . In the embodiment of the invention illustrated in  FIG. 51 , field spreader  379  is located in coolant chamber  360 . In the embodiment of the invention illustrated in  FIG. 51 , field spreader  379  may be used to, for example, spread and flatten first tissue region  1309 . In the embodiment of the invention illustrated in  FIG. 51  field spreader  379  may be used to, for example, spread and flatten lesions formed in first tissue region  1309 . 
     Further General Embodiments 
     Procedure 
     In one embodiment of the invention, electromagnetic power is delivered to the skin for a predetermined period of time. In one embodiment of the invention skin is engaged in, for example, a tissue chamber prior to the delivery of energy. In one embodiment of the invention, skin is cooled prior to the application of electromagnetic energy. In one embodiment of the invention, skin is cooled during the application of electromagnetic energy. In one embodiment of the invention, skin is cooled after the application of electromagnetic energy. In one embodiment of the invention, energy is delivered to the skin by applying a predetermined amount of power to an antenna positioned in close proximity, which may also be referred to as proximal, to the surface of the skin. In one embodiment of the invention, skin is positioned in close proximity to an electromagnetic energy device. In one embodiment of the invention, skin is positioned in close proximity to an electromagnetic energy delivery device using vacuum pressure to hold the skin in position. In one embodiment of the invention a region to be treated is anesthetized prior to treatment. In one embodiment of the invention anesthesia in the anesthetized region may change the dielectric properties of the tissue to be treated. In one embodiment of the invention, characteristics of the electromagnetic radiation irradiated through the skin are modified to account for variables, such as, for example the dielectric properties of the anesthesia, which determine anesthesia&#39;s influence on the treatment. Variables that may determine anesthesia&#39;s influence on treatment may include, for example: time from administration; vasodilatation or vasoconstriction characteristics of anesthetic; volume of anesthesia administered; anesthesia type (liquid injected, topical); location/depth in tissue anesthesia is administered; method of administration, such as, for example, one or multiple locations. In one embodiment of the invention, a template may be used to align a handpiece adapted to deliver electromagnetic energy to tissue. In one embodiment of the invention, a template may be used to align a handpiece as the handpiece is moved from position to position in, for example, the axilla. In one embodiment of the invention, a template is used to align an injection site for the delivery of, for example, anesthesia which may be, for example, lidocaine. In one embodiment of the invention, a template is used to facilitate treatment by indicating regions which have been previously treated. In one embodiment of the invention, a template may be aligned by, for example, using henna, sharpie marks or tattoos. 
     Tissue Structure 
     Regions 
     In one embodiment of the invention, tissue to be treated may be made up of layers having particular dielectric and conductivity characteristics. In one embodiment of the invention tissue having a high dielectric constant, also referred to as high dielectric tissue, may have a dielectric constant greater than approximately 25. In one embodiment of the invention tissue having a low dielectric constant, also referred to as low dielectric tissue, may have a dielectric constant less than approximately 10. In one embodiment of the invention tissue having a high conductivity, also referred to as high conductivity tissue, may have a conductivity greater than approximately 1.0 siemens per meter. In one embodiment of the invention tissue having a low conductivity, also referred to as high dielectric tissue, may have a conductivity of less than approximately 1.0 siemens per meter. 
     In one embodiment of the invention, low dielectric, low conductivity tissue may be, for example the hypodermis. In one embodiment of the invention, low dielectric tissue, low conductivity tissue, such as, for example, fat, may be tissue found in the hypodermis. In one embodiment of the invention, low dielectric, low conductivity tissue may be, for example a layer of the hypodermis below a glandular layer. In one embodiment of the invention, low dielectric tissue may be, for example the hypodermis. In one embodiment of the invention, low dielectric tissue, such as, for example, fat, may be tissue found in the hypodermis. In one embodiment of the invention, low dielectric tissue may be, for example a layer of the hypodermis below a glandular layer. 
     In one embodiment of the invention, high dielectric, high conductivity tissue may be, for example tissue found in the dermis. In one embodiment of the invention, high dielectric, high conductivity tissue may be, for example tissue found in the dermis. In one embodiment of the invention, high dielectric, high conductivity tissue may be, for example, tissue found in a glandular layer. In one embodiment of the invention, high dielectric, high conductivity tissue may be, for example, muscle tissue. 
     Glandular Layer 
     In one embodiment of the invention, a glandular layer may be, for example a layer of high dielectric, high conductivity tissue. In one embodiment of the invention, a glandular layer may be a layer of tissue with high water content. In one embodiment of the invention, a glandular layer may be a tissue layer in the region of an interface between the dermis and hypodermis which contains sufficient glandular tissue to raise the dielectric constant and conductivity of the glandular layer to a magnitude sufficient to create a standing wave pattern having a peak E-field in the glandular layer. In one embodiment of the invention, glandular tissue may occupy an average thickness of three to five millimeters in a five millimeter thick piece of human skin. In one embodiment of the invention, a glandular layer may include both apocrine gland lobules and eccrine gland lobules within the glandular layer. In one embodiment of the invention, a glandular layer may be a layer in the human axilla where substantially all of the sweat glands are localized. In one embodiment of the invention, wherein a glandular layer includes both apocrine and eccrine gland lobules, the apocrine gland modules may be more numerous and larger than the eccrine gland lobules. In one embodiment of the invention, a glandular layer may be a layer of tissue which includes a concentration of glands, such as, for example, eccrine, apoeccrine and/or apocrine sweat glands, sufficient to raise the conductivity of tissue surrounding the glands. In one embodiment of the invention, a glandular layer may be a layer of tissue which includes a concentration of glands, such as, for example, eccrine, apoeccrine and/or apocrine sweat glands, sufficient to raise the dielectric constant of tissue surrounding the glands. In one embodiment of the invention, a glandular layer may be a region of the hypodermis with sufficient glandular tissue to raise the dielectric constant of that region of the hypodermis to a magnitude sufficient to reduce or eliminate reflected electromagnetic radiation at the dermal, hypodermal interface. In one embodiment of the invention, a glandular layer may be a region of the hypodermis with sufficient glandular tissue to raise the dielectric constant of that region of the hypodermis to a magnitude sufficient to reduce or eliminate reflected electromagnetic radiation at the dermal, hypodermal interface, moving a standing wave into the hypodermis. In one embodiment of the invention, a glandular layer may be a region of the hypodermis with sufficient glandular tissue to raise dielectric constant to match the dielectric constant of the adjoining dermis. In one embodiment of the invention, a glandular layer may be a region of the hypodermis with sufficient glandular tissue to raise dielectric constant of the glandular layer to match the dielectric constant of surrounding hypodermis. In one embodiment of the invention, a glandular layer may be a region of the hypodermis with sufficient glandular tissue to raise dielectric constant of the glandular layer to exceed the dielectric constant of surrounding hypodermis. In one embodiment of the invention, a glandular layer may have a dielectric constant of greater than approximately 20. In one embodiment of the invention, a glandular layer may have a conductivity of greater than approximately 2.5 siemens per meter. 
     Interface 
     In one embodiment of the invention, a critical interface, which may also be referred to as a dielectric interface or a dielectric discontinuity, may be an interface between a layer of tissue having a high dielectric constant and high conductivity and a layer of tissue having a low dielectric constant. In one embodiment of the invention, a dielectric interface may be an interface between a layer of tissue having a high dielectric constant and high conductivity and a layer of tissue having a low dielectric constant and low conductivity. In one embodiment of the invention, a critical interface may exist at the interface between the dermis and a glandular layer. In one embodiment of the invention, a critical interface may be an interface between the dermis and the hypodermis. In one embodiment of the invention, a critical interface may be an interface between the dermis and a portion of the hypodermis. In one embodiment of the invention, a critical interface may be an interface between the dermis and a portion of the hypodermis having a limited number of sweat glands. In one embodiment of the invention, a critical interface may be an interface between the dermis and a region of the hypodermis which does not include a glandular region. In one embodiment of the invention, a critical interface may be an interface between the dermis and a region of the hypodermis which does not include a significant number of tissue structures. 
     Treatment 
     In embodiments of the invention, tissue to be treated may be treated by, for example, raising the temperature of the tissue. In embodiments of the invention, tissue to be treated may be treated by, for example, raising the temperature of the tissue to a temperature sufficient to cause a change in the tissue. In embodiments of the invention, tissue to be treated may be treated by, for example, raising the temperature of the tissue to a temperature sufficient to damage the tissue. In embodiments of the invention, tissue to be treated may be treated by, for example, raising the temperature of the tissue to a temperature sufficient to destroy the tissue. In embodiments of the invention, electromagnetic radiation is used to heat tissue to create a lesion where the lesion starts as a result of damage from heat generated by dielectric heating of tissue and the lesion is enlarged at least in part as consequence of thermal conduction of heat generated by the dielectric heating. In embodiments of the invention electromagnetic radiation may be used to heat the contents, such as, for example, sebum, of a tissue structure, such as, for example a hair follicle. In embodiments of the invention electromagnetic radiation may be used to heat the contents, such as, for example, sweat of a tissue structure, such as, for example a hair follicle. In embodiments of the invention electromagnetic radiation may be used to heat the contents, such as, for example, sebum of a tissue structure, such as, for example a hair follicle to a temperature sufficient to damage or destroy, for example, bacteria in the contents. In one embodiment of the invention, electromagnetic radiation may be used to heat tissue to a temperature sufficient to cause secondary effects in surrounding tissue or tissue structures, such as, for example, heating bacteria in surrounding tissue or surrounding tissue structures. In one embodiment of the invention, electromagnetic radiation may be used to heat tissue to a temperature sufficient to cause secondary effects in surrounding tissue or tissue structures, such as, for example, killing bacteria in surrounding tissue or surrounding tissue structures. 
     Target Tissue 
     In embodiments of the invention tissue to be treated as, for example, by raising the temperature of the tissue, may be referred to as target tissue. 
     Tissue to be Treated 
     Tissue Layers 
     In embodiments of the invention target tissue may be tissue adjacent to a dermal, hypodermal interface. In embodiments of the invention target tissue may be tissue in a dermal layer, in close proximity to a dermal, hypodermal interface. In embodiments of the invention target tissue may be deep dermal tissue. In embodiments of the invention target tissue may be tissue adjacent to a skin, fat interface. In embodiments of the invention target tissue may be tissue adjacent to a critical interface. In embodiments of the invention target tissue may be tissue adjacent to an interface between a glandular layer and a low dielectric layer. In embodiments of the invention target tissue may be tissue adjacent to an interface between a glandular layer and a layer of the hypodermis. 
     Physical Structures 
     In embodiments of the invention target tissue may be axillary tissue. In embodiments of the invention target tissue may be tissue in a hair bearing area. In embodiments of the invention target tissue may be tissue located in a region having at least 30 sweat glands per square centimeter. In embodiments of the invention target tissue may be tissue located in a region having an average of 100 sweat glands per square centimeter. In embodiments of the invention target tissue may be tissue located approximately 0.5 millimeters to 6 millimeters below the surface of the skin. In embodiments of the invention target tissue may be tissue located in a region where sweat glands, including, for example, apocrine and eccrine glands are located. In embodiments of the invention target tissue may be tissue located in a region where hair follicles are located. 
     Tissue Properties 
     In embodiments of the invention target tissue may be tissue subject to dielectric heating. In embodiments of the invention target tissue may be tissue having a high dipole moment. In embodiments of the invention, target tissue may be, for example, tissue containing exogenous materials. In embodiments of the invention target tissue may include tissue with bacteria. In embodiments of the invention target tissue may be, for example, collagen, hair follicles, cellulite, eccrine glands, apocrine glands, sebaceous glands or spider veins. In embodiments of the invention target tissue may be, for example, hair follicles. In embodiments of the invention target tissue may be, for example, regions of a hair follicle, including the lower segment (bulb and suprabulb), the middle segment (isthmus), and the upper segment (infundibulum). In embodiments of the invention target tissue may be, for example, structures associated with a hair follicle, such as, for example, stem cells. 
     Tissue Types 
     In embodiments of the invention target tissue may be human tissue. In embodiments of the invention target tissue may be porcine tissue. In embodiments of the invention target tissue may be, for example, wound tissue. In embodiments of the invention target tissue may be, for example, tissue to be insulted, as for example, skin tissue prior to surgery. In embodiments of the invention target tissue may be, for example, vessels, including veins, capillaries or arteries, supplying blood to tissue structures. 
     Effect 
     In embodiments of the invention, target tissue may be, for example, a volume of tissue defined by a region with a SAR greater than or equal to approximately fifty percent of peak SAR. In embodiments of the invention, target tissue may be, for example, a volume of tissue defined by a region with a SAR greater than or equal to between thirty and seventy percent of peak SAR. 
     Methods 
     Tissue &amp; Structures 
     In one embodiment of the invention a method of treating target tissue is described. In one embodiment of the invention a method of damaging glands is described. In one embodiment of the invention a method of damaging hair follicles is described. In one embodiment of the invention a method of destroying tissue is described. In one embodiment of the invention a method of treating skin tissue is described. In one embodiment of the invention a method of preventing damage to tissue is described. In one embodiment of the invention a method of preventing the growth of a lesion toward a skin surface is described. In one embodiment of the invention, a method of damaging or destroying stem cells associated with hair follicles is described. In one embodiment of the invention, a method of aligning electromagnetic fields to preferentially treat tissue is described. In one embodiment of the invention, a method of aligning electromagnetic fields to preferentially treat tissue having a high water content is described. In embodiments of the invention, electromagnetic energy is used to heat sebum. In one embodiment of the invention, a method of creating a lesion in selected tissue regions is described. In one embodiment of the invention, a method of selectively depositing energy in selected tissue regions is described. In one embodiment of the invention, a method of selectively heating regions of tissue is described. In one embodiment of the invention, a method of preferentially heating regions of tissue is described. 
     Radiation 
     In one embodiment of the invention, a method of controlling power deposition in tissue is described. In one embodiment of the invention, a method of controlling E-field pattern in tissue is described. In one embodiment of the invention a method of creating a volume of high power deposition in tissue is described. In one embodiment of the invention a method of controlling output of a microwave device is described. 
     Lesion 
     In one embodiment of the invention a method of creating a lesion in tissue is described. In one embodiment of the invention a method of creating a subdermal lesion in tissue is described. 
     Gradients 
     In one embodiment of the invention a method of creating a temperature gradient within tissue is described. In one embodiment of the invention a method of creating a temperature gradient having a peak at a dermal, hypodermal interface is described. In one embodiment of the invention a method of creating a temperature gradient having a peak in dermal tissue adjacent the dermal, hypodermal interface is described. In one embodiment of the invention a method of creating a temperature gradient having a peak in glandular tissue is described. In one embodiment of the invention a method of creating a temperature gradient having a peak in glandular tissue adjacent an interface between glandular tissue and hypodermal tissue is described. In one embodiment of the invention a method of creating a temperature gradient having a peak adjacent a critical interface is described. In one embodiment of the invention a method of creating an inverse power gradient in tissue is described. 
     Clinical Indications 
     In one embodiment of the invention a method of reducing sweat is described. In one embodiment of the invention a method of reducing sweat production in a patient is described. In one embodiment of the invention a method of treating axillary hyperhidrosis is described. In one embodiment of the invention a method of treating hyperhidrosis is described. In one embodiment of the invention a method of removing hair is described. In one embodiment of the invention a method of preventing the re-growth of hair is described. In one embodiment of the invention, a method of treating osmidrosis is described. In one embodiment of the invention, a method of denervating tissue is described. In one embodiment of the invention, a method of treating port wine stains is described. In one embodiment of the invention, a method of treating hemangiomas is described. In one embodiment of the invention, a method of treating psoriasis is described. In one embodiment of the invention, a method of reducing sweat is described. In one embodiment of the invention, a method of reducing sweat is described. In embodiments of the invention, electromagnetic energy is used to treat acne. In one embodiment of the invention, a method of treating sebaceous glands is described. In one embodiment of the invention, a method of destroying bacteria is described. In one embodiment of the invention, a method of destroying propionibacterium is described. In one embodiment of the invention, a method of treating reducing inflammation is described. Further conditions and structures that can be treated in some embodiments are described in, for example, pp. 3-7 of U.S. Provisional App. No. 60/912,899; and pp. 1-10 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described in, for example, pp. 8-12 of Appendix 1 and pp. 5-14 of Appendix 2. 
     In one embodiment of the invention electromagnetic energy may be used to reduce sweat. In one embodiment of the invention electromagnetic energy may be used to reduce sweat production in a patient. In one embodiment of the invention electromagnetic energy may be used to treat axillary hyperhidrosis. In one embodiment of the invention electromagnetic energy may be used to treat hyperhidrosis. In one embodiment of the invention electromagnetic energy may be used to remove hair. In one embodiment of the invention electromagnetic energy may be used to prevent the re-growth of hair. In one embodiment of the invention electromagnetic energy may be used to treat osmidrosis. In one embodiment of the invention, electromagnetic energy may be used to denervate tissue. In one embodiment of the invention electromagnetic energy may be used to treat port wine stains. In one embodiment of the invention electromagnetic energy may be used to treat hemangiomas. In one embodiment of the invention electromagnetic energy may be used to treat psoriasis. In one embodiment of the invention electromagnetic energy may be used to reduce sweat. In embodiments of the invention, electromagnetic energy may be used to treat acne. In embodiments of the invention, electromagnetic energy may be used to treat sebaceous glands. In embodiments of the invention, electromagnetic energy may be used to destroy bacteria. In embodiments of the invention, electromagnetic energy may be used to destroy propionibacterium. In embodiments of the invention, electromagnetic energy may be used to clear sebum from a hair follicle. In embodiments of the invention, electromagnetic energy may be used to clear obstructed hair follicles. In embodiments of the invention, electromagnetic energy may be used to reverse comedogenesis. In embodiments of the invention, electromagnetic energy may be used to clear blackheads. In embodiments of the invention, electromagnetic energy may be used to clear whiteheads. In embodiments of the invention, electromagnetic energy may be used to reducing inflammation. 
     Positioning 
     In one embodiment of the invention a method of positioning skin is described. In one embodiment of the invention a method of positioning a dermal, hypodermal interface is described. In one embodiment of the invention a method of positioning a critical interface is described. In one embodiment of the invention a method of positioning a skin, fat interface is described. In one embodiment of the invention a method of positioning an interface between a glandular layer and a layer of hypodermal tissue is described. In one embodiment of the invention a method of separating target tissue from muscle is described. In one embodiment of the invention a method of separating skin tissue from muscle is described. 
     Power Loss Density or Specific Absorption Rate 
     Skin 
     In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation results in a region of localized high power loss density or SAR below the skin surface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation results in a region of localized high power loss density or SAR in a region of the skin below an upper layer of the skin. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a layer of the skin adjacent a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a layer of the skin adjacent a critical interface and between the skin surface and the critical interface. 
     Dermis 
     In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a region of the dermis. In one embodiment of the invention, radiating the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a region of the dermis below an upper layer of the dermis. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a region of the dermis adjacent an interface between the dermis and the epidermis. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a region of the dermis adjacent a critical interface. 
     In embodiments of the invention, regions of localized high power loss density or regions of localized high specific absorption rate result in the deposition of sufficient energy into those regions to raise the temperature of those regions above the temperature of surrounding regions. In embodiments of the invention, regions of localized high power loss density or regions of localized high specific absorption rate result in the deposition of sufficient energy into those regions to raise the temperature of those regions to a temperature sufficient to create lesions in those regions. In embodiments of the invention, regions of localized high power loss density or regions of localized high specific absorption rate result in the deposition of sufficient energy into those regions to raise the temperature of those regions to a temperature sufficient to heat surrounding regions by, for example, thermal conductive heating. 
     Glandular Layer 
     In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a glandular layer. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a glandular layer adjacent a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a glandular layer adjacent a critical interface and below a first layer of skin. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a region of localized high power loss density or SAR in a glandular layer adjacent a critical interface and below at least a portion of the dermis. 
     Temperature Gradient 
     Skin 
     In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a region below the skin surface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a region of the skin below an upper layer of the skin. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a layer of the skin adjacent to a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a layer of the skin adjacent to a critical interface and between a critical interface and the surface of the skin. 
     Dermis 
     In one embodiment of the invention, electromagnetic radiation generates a temperature gradient where the temperature gradient has a peak in a layer of the dermis below the surface of the skin. In one embodiment of the invention, electromagnetic radiation generates a temperature gradient where the temperature gradient has a peak in a layer of the dermis below an upper layer of the dermis. In one embodiment of the invention, electromagnetic radiation generates a temperature gradient where the temperature gradient has a peak in a region of the dermis adjacent an interface between the dermis and the hypodermis. In one embodiment of the invention, electromagnetic radiation generates a temperature gradient where the temperature gradient has a peak in a region of the dermis adjacent a critical interface. 
     Glandular Layer 
     In one embodiment of the invention irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a glandular layer below the skin surface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a glandular layer adjacent a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates a temperature gradient having a peak in a glandular layer adjacent a critical interface and below a first layer of skin. 
     Inverse Power Gradient 
     Skin 
     In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a region below the skin surface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a region of the skin below an upper layer of the skin. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a layer of the skin adjacent to a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a layer of the skin adjacent to a critical interface and between a critical interface and the surface of the skin. 
     Dermis 
     In one embodiment of the invention, electromagnetic radiation generates an inverse power gradient where the inverse power gradient has a peak in a layer of the dermis below the surface of the skin. In one embodiment of the invention, electromagnetic radiation generates an inverse power gradient where the inverse power gradient has a peak in a layer of the dermis below an upper layer of the dermis. In one embodiment of the invention, electromagnetic radiation generates an inverse power gradient where the inverse power gradient has a peak in a region of the dermis adjacent an interface between the dermis and the hypodermis. In one embodiment of the invention, electromagnetic radiation generates an inverse power gradient where the inverse power gradient has a peak in a region of the dermis adjacent a critical interface. 
     Glandular Layer 
     In one embodiment of the invention irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a glandular layer below the skin surface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a glandular layer adjacent a critical interface. In one embodiment of the invention, irradiating tissue through the surface of skin with electromagnetic radiation generates an inverse power gradient having a peak in a glandular layer adjacent a critical interface and below a first layer of skin. 
     Lesion 
     Skin 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion in a region below the skin surface. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in a region below the skin surface where the lesion starts in a layer below an upper layer of the skin. In one embodiment of the invention, is used to create a lesion in skin where the lesion starts in a layer of the skin adjacent a critical interface. In one embodiment of the invention, is used to create a lesion in skin where the lesion starts in a layer of the skin adjacent a critical interface and between the skin surface and the critical interface. 
     Dermis 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin where the lesion starts in a layer of the dermis below the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin where the lesion starts in a layer of the dermis below an upper layer of the dermis. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin, where the lesion starts in a region of the dermis in close proximity to the interface between the dermis and the hypodermis. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin, where the lesion starts in a region of the dermis adjacent a critical interface. 
     Glandular Layer 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer. In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer adjacent a critical interface. In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer adjacent a critical interface and below a first layer of skin. 
     Skin 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion in a region below the skin surface in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in a region below the skin surface where the lesion starts in a layer below an upper layer of the skin in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, is used to create a lesion in skin where the lesion starts in a layer of the skin adjacent a critical interface in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, is used to create a lesion in skin where the lesion starts in a layer of the skin adjacent a critical interface and between the skin surface and the critical interface in the absence of any external mechanism for removing heat from the surface of the skin. 
     Dermis 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin where the lesion starts in a layer of the dermis below the surface of the skin in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin where the lesion starts in a layer of the dermis below an upper layer of the dermis in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin, where the lesion starts in a region of the dermis in close proximity to the interface between the dermis and the hypodermis in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion in skin, where the lesion starts in a region of the dermis adjacent a critical interface in the absence of any external mechanism for removing heat from the surface of the skin. 
     Glandular Layer 
     In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer adjacent a critical interface in the absence of any external mechanism for removing heat from the surface of the skin. In one embodiment of the invention, electromagnetic radiation is used to create a lesion which starts in a glandular layer adjacent a critical interface and below a first layer of skin in the absence of any external mechanism for removing heat from the surface of the skin. 
     Lesion Origin 
     In one embodiment of the invention, a lesion origin may be located at a point or region in high dielectric, high conductivity tissue adjacent low dielectric tissue. In one embodiment of the invention, a lesion origin may be a point or region in tissue where a tissue reaches a temperature sufficient to allow a lesion to begin to grow. In one embodiment of the invention, a lesion origin may be located at a point or region in high dielectric, high conductivity tissue adjacent a critical interface. In one embodiment of the invention, the lesion origin may be located at a point or region where microwave energy radiated through the surface of the skin generates a standing wave pattern having a peak E-field. In one embodiment of the invention, the lesion origin may be located in high dielectric/high conductivity tissue near a critical interface where microwave energy radiated through the surface of the skin generates constructive interference. 
     Electromagnetic Radiation Characteristics 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific E-field characteristics. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the polarization of the E-field component of the electromagnetic radiation is substantially parallel to the skin&#39;s outer surface. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the E-field component of the electromagnetic radiation is substantially parallel to at least one interface between tissue layers within the skin. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the E-field component of the electromagnetic radiation is substantially parallel to a critical interface. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the E-field component of the electromagnetic radiation is substantially parallel to the interface between the dermis and the hypodermis. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the E-field component of the electromagnetic radiation is substantially parallel to the interface between a glandular layer and a portion of the hypodermis. In one embodiment of the invention, an E-field component may be considered to be substantially parallel to, for example, a critical interface when such E-field component is substantially parallel to an idealized average interface, such as, for example, the idealized interface  1308  or  1333  used in the Figures. In one embodiment of the invention, an E-field component may be considered to be substantially parallel to, for example, a critical interface when such E-field component is substantially parallel to at least a portion of such interface, such as, for example, a portion of such interface underlying an aperture of an antenna radiating the E-field. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific polarization characteristics. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the electromagnetic radiation is polarized such that the E-field component of the electromagnetic radiation is substantially parallel to the skin&#39;s outer surface. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the electromagnetic radiation is polarized such that the E-field component of the electromagnetic radiation is substantially parallel to at least one interface between tissue layers within the skin. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the electromagnetic radiation is polarized such that the E-field component of the electromagnetic radiation is substantially parallel to the interface between the dermis and the hypodermis. In one embodiment of the invention, skin is irradiated with electromagnetic radiation wherein the electromagnetic radiation is polarized such that the E-field component of the electromagnetic radiation is substantially parallel to an interface between a glandular layer and the hypodermis. 
     In one embodiment of the invention, an E-field may be made up of at least two E-field components, wherein one of said E-field components is parallel to a skin surface or a critical interface and a second E-field component is perpendicular to the first E-field component. In one embodiment of the invention, an E-field may be substantially parallel to a surface or interface when the magnitude of an E-field component parallel to that surface or interface is greater than 75 percent of the total E-field magnitude. In one embodiment of the invention, an E-field may be made up of a transverse E-field component and a perpendicular E-field component. In one embodiment of the invention, an E-field may be made up a transverse E-field component may be parallel to a skin surface or a critical interface. In one embodiment of the invention, an E-field may be substantially parallel to a surface or interface when the magnitude of a transverse E-field component is greater than 75 percent of the total E-field magnitude. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific frequency characteristics. In one embodiment of the invention, skin is irradiated by electromagnetic radiation having a frequency of approximately 5.8 GHz. In one embodiment of the invention, skin is irradiated by electromagnetic radiation having a frequency of between 5 GHz and 6.5 GHz. In one embodiment of the invention, skin is irradiated by electromagnetic radiation having a frequency of between 4.0 GHz and 10 GHz. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics within tissue. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a constructive interference pattern having a peak within the skin. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a constructive interference pattern in the dermis, wherein the constructive interference pattern has a peak in a region of the dermis which is below a first layer of the dermis and where destructive interference occurs in the first layer of the dermis. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a constructive interference pattern, wherein the constructive interference pattern has a peak adjacent a critical interface. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a constructive interference pattern having a peak in a glandular layer. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a constructive interference pattern that generates a peak electric field in a tissue layer. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a constructive interference pattern that generates a region of localized high power loss density, SAR or tissue temperature. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics within skin. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a destructive interference pattern within the skin. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a destructive interference pattern that generates a minimum electric field in a tissue layer. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a destructive interference pattern that generates a region of localized low power loss density, SAR or tissue temperature. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a destructive interference pattern in the dermis, wherein the destructive interference pattern has a peak in a region of the dermis which is above a deep layer of the dermis. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a destructive interference pattern having a peak in tissue between a skin surface and a glandular layer. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics within tissue. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a standing wave pattern within the skin. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a standing wave pattern having a peak in the dermis below a first layer of the dermis. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a standing wave pattern having a peak adjacent a critical interface. In one embodiment of the invention, skin is irradiated by electromagnetic radiation which generates a standing wave pattern having a peak in a glandular layer. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a standing wave pattern that generates a peak electric field. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a standing wave pattern that generates a region of localized high power loss density, SAR or tissue temperature. In one embodiment of the invention, skin irradiated with electromagnetic radiation generates a standing wave pattern that generates a region of localized low power loss density, SAR or tissue temperature. 
     Antenna 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the position of the antenna radiating the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by electromagnetic radiation generated by an antenna positioned in close proximity to the skin surface. In one embodiment of the invention, skin is irradiated by an antenna located in the radiating near field region with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna located substantially in the radiating near field region with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna located less than one half of one wavelength from the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna located less than one half of one wavelength from the surface of adjacent skin, wherein a wavelength is measured in dielectric material separating the antenna from the skin surface. In one embodiment of the invention, skin is irradiated by an antenna located less than one half of one wavelength from the surface of adjacent skin, wherein a wavelength is measured in cooling fluid separating the antenna from the skin surface. In one embodiment of the invention, skin is irradiated by an antenna located less approximately 3 millimeters from the skin surface. In one embodiment of the invention, skin is irradiated by an antenna located less approximately 1.5 millimeters from the skin surface. In one embodiment of the invention, wavelength of a radiated signal is the wavelength in air divided by the square root of the dielectric constant of materials separating the antenna from the skin surface. In one embodiment of the invention, wavelength of a radiated signal is the wavelength in air divided by the square root of the dielectric constant of cooling fluid separating the antenna from the skin surface. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the position of the output of the antenna radiating the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna having an output in the radiating near field region with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna having an output outside the reactive near field region with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna having an output which is not in the far field region with respect to the surface of adjacent skin. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics related to the position of a radiating aperture in the antenna radiating the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna having a radiating aperture in the radiating near field region with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna having a radiating aperture outside the reactive near field with respect to the surface of adjacent skin. In one embodiment of the invention, skin is irradiated by an antenna having a radiating aperture which is not in the far field region with respect to the surface of adjacent skin. 
     In one embodiment of the invention, a reactive near field region may be, for example, that portion of the near field region immediately surrounding the antenna where the near reactive field predominates. In one embodiment of the invention, an antenna may be located a distance from a skin surface which may be approximately 0.62 times the square root of D 3 /Lambda, where D is the largest physical dimension of the antenna aperture and Lambda is the wavelength of the electromagnetic radiation transmitted by the antenna measured in the medium positioned between the antenna output and skin surface. In one embodiment of the invention, a radiating near field region may be, for example, that that region of the field of an antenna between the reactive near field region and the far field region wherein radiation fields predominate. In one embodiment of the invention, an antenna may be located a maximum distance from a skin surface which may be approximately 2 times D 2 /Lambda, where D is the largest physical dimension of the antenna aperture and Lambda is the wavelength of the electromagnetic radiation transmitted by the antenna measured in the medium positioned between the antenna output and skin surface. In one embodiment of the invention, an antenna may be located a less than approximately 2 times D 2 /Lambda In one embodiment of the invention, a far field region may be, for example, that region of the field of an antenna where the angular field distribution is essentially independent of the distance from the antenna. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the configuration of the antenna which radiates the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate a field pattern primarily in the TE mode. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate a field pattern primarily in the TE 10  mode. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate a field pattern solely in TE 10  mode. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate a field pattern primarily in the TEM mode. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate a field pattern solely in TEM mode. In embodiments of the invention, TE, TEM and TE 10  are particularly useful as they are modes in which radiated electromagnetic energy includes E-Fields in the transverse direction. Thus, where an antenna is positioned appropriately, an antenna transmitting electromagnetic energy in a TE, TEM or TE 10  mode will generate an E-field which may be parallel or substantially parallel to a skin surface adjacent the antenna or to a critical interface, such as, for example, an interface between the dermis and the hypodermis. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the configuration of the antenna which radiates the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate electromagnetic energy having an E-field component which is substantially parallel to the surface of the skin. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate electromagnetic energy having an E-field component which is substantially parallel to a critical interface. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate electromagnetic energy having an E-field component which is substantially parallel to the interface between the dermis and the hypodermis. In one embodiment of the invention, skin is irradiated by an antenna configured to radiate electromagnetic energy having an E-field component which is substantially parallel to an interface between a glandular region and a portion of the hypodermis. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the configuration of the antenna which radiates the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna configured to generate a standing wave in adjacent tissue. In one embodiment of the invention, skin is irradiated by an antenna configured to generate a standing wave in adjacent tissue wherein the standing wave has a peak adjacent a critical interface. In one embodiment of the invention, skin is irradiated by an antenna configured to generate a standing wave in adjacent tissue wherein the standing wave has a peak in dermal tissue adjacent a dermal, subdermal interface. In one embodiment of the invention, skin is irradiated by an antenna configured to generate a standing wave in adjacent tissue wherein the standing wave has a peak in a glandular layer. 
     In one embodiment of the invention, skin is irradiated by electromagnetic radiation having specific characteristics and, more particularly, specific characteristics resulting from the configuration of the antenna which radiates the electromagnetic radiation. In one embodiment of the invention, skin is irradiated by an antenna configured to generate constructive interference in adjacent tissue. In one embodiment of the invention, skin is irradiated by an antenna configured to generate constructive interference in adjacent tissue wherein the constructive interference has a peak adjacent a critical interface. In one embodiment of the invention, skin is irradiated by an antenna configured to generate constructive interference in adjacent tissue wherein the standing wave has a peak in dermal tissue adjacent a dermal, subdermal interface. In one embodiment of the invention, skin is irradiated by an antenna configured to generate constructive interference in adjacent tissue wherein the standing wave has a peak in a glandular layer. 
     Heating Tissue/Tissue Structures 
     In one embodiment of the invention, tissue is heated by conducting heat generated in a lesion to specified tissue. In one embodiment of the invention, tissue is heated by conducting heat generated in a lesion through intermediate tissue wherein heat in the lesion is generated primarily by dielectric heating. In one embodiment of the invention, tissue located below a critical interface is heated by conducting heat generated in a lesion across the critical interface. In one embodiment of the invention, a method is described for heating tissue located below a critical interface by conducting heat generated in a lesion located above the critical interface wherein heat generated in the lesion is generated primarily by dielectric heating and heat below the critical interface is generated primarily by conduction of heat from the lesion through intermediate tissue to tissue located below a dielectric barrier. 
     In one embodiment of the invention, tissue structures, such as, for example sweat glands or hair follicles, located in the region of the skin near a critical interface are heated. In one embodiment of the invention, tissue structures located near a critical interface are heated primarily by conduction of heat from a lesion. In one embodiment of the invention, tissue structures located near a critical interface are heated primarily by conduction of heat from a lesion, wherein the lesion is created by dielectric heating. In one embodiment of the invention, tissue structures located in a first tissue layer are heated by heat generated in the first tissue layer as a result of a standing wave generated in the first tissue layer by reflections off a critical interface 
     In one embodiment of the invention, tissue structures located in the region of the skin where the dermis and hypodermis layer meet are heated. In one embodiment of the invention, tissue structures located in a glandular layer are heated. In one embodiment of the invention, tissue structures located in the region of the skin where the dermis and hypodermis layer meet are damaged. In one embodiment of the invention, tissue structures located in a glandular layer are damaged. In one embodiment of the invention, tissue structures located in the region of the skin where the dermis and hypodermis layer meet are destroyed. In one embodiment of the invention, tissue structures located in a glandular layer are destroyed. In one embodiment of the invention, tissue elements are heated by conducting heat generated in a lesion through intermediate tissue to the tissue elements, wherein heat in the lesion is generated primarily by dielectric heating. In one embodiment of the invention, tissue structures located below a critical interface are heated by conducting heat generated in a lesion above the critical interface primarily by dielectric heating through intermediate tissue to tissue structures located below a the critical interface. 
     In one embodiment of the invention a region adjacent a critical interface may be heated by depositing more energy into that region than into surrounding tissue. In one embodiment of the invention, tissue in the dermal layer, adjacent to the interface between the dermal layer and the subdermal layer is preferentially heated. In one embodiment of the invention, tissue in a glandular layer is preferentially heated. In one embodiment of the invention, tissue in a glandular layer adjacent a critical interface is preferentially heated. 
     Cooling 
     In one embodiment of the invention, heat generated in tissue below the surface of the skin is prevented from damaging tissue adjacent the surface of the skin by removing heat from the surface of the skin. In one embodiment of the invention, heat generated in tissue below the surface of the skin is prevented from damaging tissue adjacent the surface of the skin by cooling the surface of the skin. 
     In one embodiment of the invention, a method is described for preventing heat generated in a lesion by dielectric heating from damaging tissue in a skin layer positioned between the lesion and the surface of the skin. In one embodiment of the invention, a method is described for preventing heat generated in a lesion by dielectric heating from damaging tissue in a skin layer positioned between the lesion and the surface of the skin by removing heat from a skin surface. In one embodiment of the invention, a method is described for preventing heat generated in a lesion by dielectric heating from damaging tissue in a skin layer positioned between the lesion and the surface of the skin by cooling a skin surface. 
     In one embodiment of the invention, a method is described for preventing heat generated in a lesion having an origin in a layer of tissue from damaging tissue in a layer of tissue positioned between the lesion origin and the surface of the skin. In one embodiment of the invention, a method is described for preventing heat generated in a lesion having an origin in a layer of tissue from damaging tissue in a skin layer positioned between the lesion and the surface of the skin by removing heat from a skin surface. In one embodiment of the invention, a method is described for preventing heat generated in a lesion having an origin in a layer of tissue from damaging tissue in a skin layer positioned between the lesion and the surface of the skin by cooling a skin surface. 
     In one embodiment of the invention, a method is described for preventing lesion from growing toward the surface of the skin. In one embodiment of the invention, a method is described for preventing lesion from growing toward the surface of the skin by removing heat from the skin surface. In one embodiment of the invention, a method is described for preventing lesion from growing toward the surface of the skin by cooling the skin surface. 
     In one embodiment of the invention, cooling may be turned off for a period after energy is delivered and resumed thereafter. In one embodiment of the invention, cooling may be turned off for a period of for example, approximately 2 seconds after energy is delivered. In one embodiment of the invention, cooling turned on and off in a pulsed manner to control the amount of heat removed through the skin surface. 
     Antenna System 
     Antenna Types 
     In embodiments of the invention, antenna  358  may be, for example: a coaxial single slot antenna; a coaxial multiple slot antenna; a printed slot antenna; a waveguide antenna; a horn antenna; a patch antenna; a patch trace antenna; a Vivaldi antenna; or a waveguide antenna. In embodiments of the invention, an antenna may be, for example an array of antennas. In embodiments of the invention, an antenna may be, for example an array of antennas wherein one or more of the antennas radiate electromagnetic energy at the same time. In embodiments of the invention, an antenna may be, for example an array of antennas wherein at least one but not all of the antennas radiate electromagnetic energy at the same time. In embodiments of the invention, an antenna may be, for example, two or more different types of antennas. In embodiments of the invention, specific antennas in an array may be selectively activated or deactivated. Additional embodiments of antennas that can be used in conjunction with embodiments and components of the present application can be found, for example, in U.S. Provisional Application No. 60/912,899, entitled METHODS AND APPARATUS FOR REDUCING SWEAT PRODUCTION, filed Apr. 19, 2007, incorporated by reference in its entirety, e.g., in FIGS. 3, 4, 5, 6C, 12F, 34A, and 38 and the accompanying description, as well as in U.S. Provisional Application No. 61/013,274, entitled METHODS, DEVICES, AND SYSTEMS FOR NON-INVASIVE DELIVERY OF MICROWAVE THERAPY, filed Dec. 12, 2007 and incorporated by reference in its entirety, e.g., in FIGS. 2C, 3A, 5, 6, 11A, 11B, 20, 21A, 21B, 22, 22A and 23. 
     Return Loss/Bandwidth 
     In one embodiment of the invention, an antenna has an optimized return loss (S 11 ) profile centered on 5.8 GHz. S11 in dB or return loss (the magnitude of S 11  in dB) is a measure of reflected power measured at antenna feed divided by the incident power at the antenna feed, which it may be used as a power transfer measurement. In one embodiment of the invention, an antenna has an optimal coupling value may be, for example, −15 dB or below, which corresponds to 97% power return loss. At 97% power coupling, 97% of the input power available to the antenna (e.g., from a microwave generator) is coupled into the antenna&#39;s input port. Alternatively, in one embodiment of the invention, an antenna has an optimal coupling value of, for example, −10 dB or below, which corresponds to 90% power coupling. Alternatively, in one embodiment of the invention, an antenna has an optimal coupling value which may be, for example, −7 dB or below, which corresponds to 80% power coupling. In one embodiment of the invention, an antenna, such as, for example, a wave guide antenna may include tuning screws. In one embodiment of the invention, tuning screws may be used to, for example, optimize the return loss (magnitude of S 11 ) for the expected load. 
     In one embodiment of the invention, an antenna is optimized to maintain the power coupled into the antenna with a return of −10 dB or better over an optimal frequency band. An optimal bandwidth may be, for example, approximately 0.25 GHz (0.125 GHz on either side of the center frequency), at frequencies of interest, such as, for example, 5.8 GHz. An optimal bandwidth may be, for example, approximately 1.0 GHz (0.5 GHz on either side of the center frequency), at frequencies of interest, such as, for example, 5.8 GHz. 
     Dielectric Filler 
     In embodiments of the invention, dielectric filler may have a dielectric constant of approximately 10. In embodiments of the invention, dielectric filler may have a dielectric constant of between approximately 9.7 and 10.3. In embodiments of the invention, dielectric filler may be impervious to fluid, including cooling fluid in cooling chamber. In embodiments of the invention, dielectric filler may be configured to prevent liquid from entering waveguide tubing. In embodiments of the invention, dielectric filler may be configured to efficiently couple energy from an antenna feed into tissue. In embodiments of the invention, dielectric filler may be configured to match a waveguide tubing, coolant chamber, including cooling fluid and skin at a predetermined frequency of, for example frequencies in the range of: between approximately 4 GHz and 10 GHz; between approximately 5 GHz and 6.5 GHZ; or frequencies of approximately 5.8 GHz. In embodiments of the invention, dielectric filler may be configured to generate a field having minimal electric field perpendicular to a tissue surface. In embodiments of the invention, dielectric filler may be configured to generate a TE, TE 10 , or TEM field in target tissue frequencies in the range of: between approximately 4 GHz and 10 GHz; between approximately 5 GHz and 6.5 GHZ; or frequencies of approximately 5.8 GHz. 
     In one embodiment of the invention, a waveguide fabricated using a cross sectional inner geometry, such as, for example, the cross-sectional inner geometry of a WR62 waveguide tube, having a width of 15.8 millimeters and a height of 7.9 millimeters is optimized at a predetermined frequency by selecting an appropriate dielectric filler. In one embodiment of the invention, an antenna, such as a waveguide antenna fabricated using a WR62 waveguide tube, is optimized at a predetermined frequency by selecting an appropriate filler material. In one embodiment of the invention, an antenna, such as a waveguide antenna fabricated using a wr62 waveguide tube, is optimized at a predetermined frequency by selecting a filler material having a dielectric constant in the range of between 3 and 12. In one embodiment of the invention, an antenna, such as a waveguide antenna fabricated using a wr62 waveguide tube, is optimized at a predetermined frequency by selecting a filler material having a dielectric constant of approximately 10. In one embodiment of the invention, an antenna, such as a waveguide antenna fabricated using a wr62 waveguide tube, is optimized at a predetermined frequency by selecting a dielectric filler material which is impervious to fluids, such as, for example cooling fluids. In one embodiment of the invention, an antenna, such as a waveguide antenna fabricated using a wr62 waveguide tube, is optimized at a predetermined frequency by selecting a dielectric filler material which is, for example, Eccostock. In one embodiment of the invention, an antenna, may be optimized at a predetermined frequency by selecting a dielectric filler material which is, for example, polycarbonate, Teflon, plastic or air. 
     Field Spreader 
     In one embodiment of the invention, an antenna may include a dielectric element, which may be referred to as a field spreader, at the antenna output that perturbs or scatters the microwave signal in such a way that the E-field is applied to tissue over a wider area. In one embodiment of the invention, the field spreader causes the E-field to diverge as it exits the antenna. In one embodiment of the invention, a field spreader may have a dielectric constant of between 1 and 80. In one embodiment of the invention, a field spreader may have a dielectric constant of between 1 and 15. In embodiments of the invention, field spreaders may be used to, for example, spread and flatten peak SAR regions, peak temperature regions or peak power loss density regions in tissue. In embodiments of the invention, field spreaders may be used to, for example, spread and flatten lesions in tissue. 
     In one embodiment of the invention, a field spreader may be a dielectric element. In one embodiment of the invention, a field spreader may be configured to spread an E-field. In one embodiment of the invention, a field spreader may be configured to extend from an output of an antenna to a cooling plate. In one embodiment of the invention, a field spreader may be configured to extend from a dielectric filler to a cooling plate. In one embodiment of the invention, a field spreader may be positioned at least partially in a cooling chamber. In one embodiment of the invention, a field spreader may be positioned at least partially in a cooling fluid. In one embodiment of the invention, a field spreader may be configured to have rounded features. In one embodiment of the invention, a field spreader may be oval. In one embodiment of the invention, a field spreader positioned at least partially in a cooling fluid may have a contoured shape. In one embodiment of the invention, a field spreader positioned at least partially in a cooling fluid may be configured to prevent eddy currents in the cooling fluid. In one embodiment of the invention, a field spreader positioned at least partially in a cooling fluid may be configured to prevent air bubbles from forming in the cooling fluid. In one embodiment of the invention, a system may have multiple field spreaders. 
     In one embodiment of the invention, a field spreader may be configured to have a dielectric constant which matches a dielectric filler. In one embodiment of the invention, a field spreader may be configured to have a dielectric constant which differs from a dielectric filler. In one embodiment of the invention, a field spreader may be configured to increase the effective field size (EFS) by reducing field strength in the center of a waveguide. In one embodiment of the invention, field spreader may be configured to increase the ratio of 50% SAR contour area at depth in a cross section of the target tissue compared to the surface area of the radiating aperture by, for example, reducing field strength in center of a waveguide. In one embodiment of the invention, field spreader may be configured to increase the lateral size of 50% SAR contour area at depth in a cross section of in the target tissue compared to the surface area of the radiating aperture by, for example, reducing field strength in the center of a waveguide. In one embodiment of the invention, a field spreader may be configured to cause a signal emitted from an antenna to diverge around the field spreader creating local E-field peaks that re-combine. In one embodiment of the invention, a field spreader may be configured to cause a signal emitted from an antenna to diverge around the field spreader creating local E-field peaks that re-combine to form larger peak power loss density, SAR or tissue temperature regions in adjacent tissue. In one embodiment of the invention, a field spreader may be configured to cause a signal emitted from an antenna to diverge around the field spreader creating local E-field peaks that re-combine to laterally enlarge lesions in adjacent tissue. In one embodiment of the invention, a field spreader may be configured to cause a signal emitted from an antenna to diverge around the field spreader creating local E-field peaks that re-combine to form laterally enlarged peak power loss density, SAR or tissue temperature regions in adjacent tissue. In one embodiment of the invention, a field spreader may be configured to cause a signal emitted from an antenna to diverge around the field spreader creating local E-field peaks that re-combine to form laterally enlarged lesions in adjacent tissue. In one embodiment of the invention, a field spreader may have a cross sectional which is between approximately two percent and 50 percent of the inner face of a waveguide antenna. In one embodiment of the invention, the field spreader may have a rectangular cross section. In one embodiment of the invention, the field spreader may have a rectangular cross section of 6 millimeters by 10 millimeters. In one embodiment of the invention, the field spreader may have a rectangular cross section of 6 millimeters by 10 millimeters when used with a waveguide having an inner face of 15.8 millimeters by 7.9 millimeters. In one embodiment of the invention, a field spreader may have a rectangular cross section of approximately 60 square millimeters. In one embodiment of the invention, afield spreader may have a rectangular cross section of approximately 60 square millimeters when used with a waveguide having an inner face with an area of approximately 124 square millimeters. In one embodiment of the invention, the field spreader may be comprised of, for example, alumina, having a dielectric constant of, for example 10. In one embodiment of the invention, a field spreader may be configured to consist of a dielectric region embedded in a waveguide. In one embodiment of the invention, a field spreader may be configured to consist of a dielectric region positioned in a cooling chamber. In one embodiment of the invention, a field spreader may be configured to consist of a notch in dielectric filler. In one embodiment of the invention, a field spreader may be configured to consist of a notch in dielectric filler which is configured to allow cooling fluid, such as, for example, water to flow in the notch. In one embodiment of the invention, a field spreader may be configured to consist of cooling fluid. In one embodiment of the invention, a field spreader may be configured to consist of one or more air gaps. In one embodiment of the invention, a field spreader may be positioned in the center of an aperture of an adjacent antenna. In one embodiment of the invention, a field spreader may comprise multiple field spreaders. In one embodiment of the invention, a field spreader may have a racetrack or ovoid shape. In one embodiment of the invention, a field spreader may have a racetrack shape and a length of, for example, 7 millimeters. In one embodiment of the invention, a field spreader may have a racetrack shape and a width of, for example, 4 millimeters. 
     Efficiency/Fringing 
     In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, is optimized to reduce or eliminate free space radiation due to fringing fields. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, is optimized to redirect fringing fields towards tissue. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna is optimized to improve the efficiency of the antenna, which efficiency may be measured by, for example comparing the energy available at the input of the antenna to the energy which is coupled into adjacent tissue. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna is optimized to improve the efficiency of the antenna such that at least seventy percent of the energy available at the input of the antenna is deposited in tissue adjacent to an output of the antenna. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, may be optimized by positioning the output of the antenna such that at least an outer edge of the waveguide tube of the waveguide antenna is in contact with fluid. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, may be optimized by positioning the output of the antenna such that the output of the antenna is in contact with fluid. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, may be optimized by positioning the output of the antenna such that an output of the antenna is covered by an insulator which separates the output from a fluid, the insulator having a thickness which reduces the free space radiation due to the fringing fields at the output of the waveguide. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna, may be optimized by positioning the output of the antenna such that an output of the antenna is covered by an insulator which separates the output from a fluid, such as, for example, a cooling fluid the insulator having a thickness of less than 0.005″. In one embodiment of the invention power transfer from an antenna, such as, for example, a waveguide antenna, through a cooling fluid and into adjacent tissue is optimized by reducing the thickness of an isolation layer between the output of the antenna and the cooling fluid. In one embodiment of the invention power transfer from an antenna, such as, for example, a waveguide antenna, through a cooling fluid and into adjacent tissue is optimized by placing the output of the antenna into the cooling fluid. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator, such as, for example, polycarbonate having a dielectric constant which is less than a dielectric constant of an antenna filler material. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator, such as, for example, polycarbonate having a dielectric constant which is less than a dielectric constant of an antenna filler material, the thickness of the insulator being between approximately 0.0001″ and 0.006″. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator the thickness of the insulator being between approximately 0.015″. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator, such as, for example, polycarbonate having a dielectric constant which is less than a dielectric constant of an antenna filler material, the thickness of the insulator being between approximately 0.0001″ and 0.004″. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator, such as, for example, polycarbonate having a dielectric constant which is less than a dielectric constant of an antenna filler material, the thickness of the insulator is approximately 0.002″. In one embodiment of the invention an antenna, such as, for example, a waveguide antenna, may be optimized by covering the output of the antenna with an insulator, such as, for example, alumina having a dielectric constant which is substantially equal to the dielectric constant of an antenna filler material. 
     Polarization 
     In one embodiment of the invention, an antenna may be optimized by, for example, optimizing the design of the antenna to ensure that the antenna radiates in a TE mode. In one embodiment of the invention, an antenna may be optimized by, for example, optimizing the design of the antenna to ensure that the antenna radiates in a TEM mode. In one embodiment of the invention, an antenna, such as, for example, a waveguide antenna may be optimized by, for example, optimizing the design of the antenna to ensure that the antenna radiates in a substantially pure TE 10  mode. 
     Cooling System 
     In one embodiment of the invention, a cooling system is placed between a device adapted to emit electromagnetic radiation and skin. In one embodiment of the invention, a cooling system includes a cooling fluid and a cooling plate. In one embodiment of the invention, a cooling system includes a cooling fluid flowing past a cooling plate. In one embodiment of the invention, a cooling fluid flows through a cooling chamber. In one embodiment of the invention, a cooling fluid flows through a cooling chamber which is positioned between a device adapted to emit electromagnetic radiation and a cooling plate. In one embodiment of the invention, a cooling system includes a tissue interface. In one embodiment of the invention, a cooling system may be incorporated into a tissue head. Other cooling systems and various components that may be used with systems and devices described herein are described and illustrated, for example, at FIGS. 33-36 and pp. 40-45 of U.S. Provisional App. No. 60/912,899; and FIGS. 11A-11B and pp. 21-24 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described, for example, in FIGS. 33-36 and pp. 42-46 of Appendix 1 and FIGS. 11A-11B and pp. 27-29 of Appendix 2. 
     Temperature 
     In one embodiment of the invention, a cooling system is optimized to maintain skin surface at a predetermined temperature. In one embodiment of the invention, a cooling system is optimized to maintain skin surface at a temperature of less than 45° C. In one embodiment of the invention, a cooling system is optimized to maintain skin surface at a temperature of less than 40° C. In one embodiment of the invention, a cooling system is optimized to maintain skin surface at a temperature of approximately 22° C. In one embodiment of the invention, a cooling system is optimized to maintain a cooling plate at a temperature of less than 40° C. In one embodiment of the invention, a cooling system is optimized to maintain skin surface at a temperature of less than 45° C. In one embodiment of the invention, cooling fluid is used remove heat from the cooling system. 
     Cooling Fluid 
     In one embodiment of the invention, moving cooling fluid is used to remove heat from the cooling system. In one embodiment of the invention, cooling fluid has a temperature of between −5° C. and 40° C. as it enters a cooling chamber in the cooling system. In one embodiment of the invention, cooling fluid has a temperature of between 10 and 25° C. as it enters a cooling chamber in the cooling system. In one embodiment of the invention, cooling fluid has a temperature of approximately 22° C. as it enters a cooling chamber in the cooling system. In one embodiment of the invention, cooling fluid has a flow rate of at least 100 milliliters per second as it moves through a cooling chamber. In one embodiment of the invention, cooling fluid has a flow rate of between 250 and 450 milliliters per second as it moves through a cooling chamber. In one embodiment of the invention, cooling fluid has a velocity of between 0.18 and 0.32 meters per second as it moves through a cooling chamber. In one embodiment of the invention, coolant flow in a cooling chamber is non-laminar. In one embodiment of the invention, coolant flow in a cooling chamber is turbulent to facilitate heat transfer. In one embodiment of the invention, cooling fluid has a Reynolds number of between approximately 1232 and 2057 prior to entering a cooling chamber. In one embodiment of the invention, cooling fluid has a Reynolds number of between approximately 5144 and 9256 prior to entering a cooling chamber. 
     In one embodiment of the invention, cooling fluid is optimized to be substantially transparent to microwave energy. In one embodiment of the invention, cooling fluid is optimized to minimize absorption of electromagnetic energy. In one embodiment of the invention, cooling fluid is optimized to match an antenna to tissue. In one embodiment of the invention, cooling fluid is optimized to facilitate the efficient transfer of microwave energy to tissue. In one embodiment of the invention, cooling fluid is optimized to conduct heat away from the surface of skin. In one embodiment of the invention, cooling fluid is comprised of a fluid having a high dielectric constant. In one embodiment of the invention, a cooling fluid is optimized to have a high dielectric constant of between 70 and 90. In one embodiment of the invention, a cooling fluid is optimized to have a high dielectric constant of approximately 80. In one embodiment of the invention, a cooling fluid is optimized to have a low dielectric constant of between 2 and 10. In one embodiment of the invention, a cooling fluid is optimized to have a low dielectric constant of approximately 2. In one embodiment of the invention, a cooling fluid is optimized to have a dielectric constant of approximately 80. In one embodiment of the invention, cooling fluid is comprised, at least in part, of de-ionized water. In one embodiment of the invention, cooling fluid is comprised, at least in part, of alcohol. In one embodiment of the invention, cooling fluid is comprised, at least in part, of ethylene glycol. In one embodiment of the invention, cooling fluid is comprised, at least in part, of glycerol. In one embodiment of the invention, cooling fluid is comprised, at least in part, of a germicide. In one embodiment of the invention, cooling fluid is comprised, at least in part of vegetable oil. In one embodiment of the invention, cooling fluid is comprised of a fluid having a low electrical conductivity. In one embodiment of the invention, cooling fluid is comprised of a fluid having an electrical conductivity of less than approximately 0.5 siemens per meter. 
     Cooling Plate 
     In embodiments of the invention, a cooling plate may be, for example configured to contact skin. In embodiments of the invention, a cooling plate may be, for example configured cool skin tissue. In embodiments of the invention, a cooling plate may be, for example configured to physically separate skin tissue from a microwave antenna. In embodiments of the invention, a cooling plate may be, for example configured to conform to the hair bearing region of the axilla of a human In embodiments of the invention, a cooling plate may be, for example configured to constitute a thermoelectric cooler. In embodiments of the invention, a cooling plate may be, for example configured to be thermally conductive. In embodiments of the invention, a cooling plate may be, for example configured to be substantially transparent to microwave energy. In embodiments of the invention, a cooling plate may be, for example configured to be thin enough to minimize microwave reflection. In embodiments of the invention, a cooling plate may be, for example configured to be composed of ceramic In embodiments of the invention, a cooling plate may be, for example configured or to be composed of alumina. 
     In one embodiment of the invention, a cooling plate is optimized to conduct electromagnetic energy to tissue. In one embodiment of the invention, a cooling plate is optimized to conduct heat from the surface of skin into a cooling fluid. In one embodiment of the invention, a cooling plate is optimized to have a thickness of between 0.0035″ and 0.025″, and may include thickness of up to 0.225″. In one embodiment of the invention, a cooling plate is optimized to have a dielectric constant of between 2 and 15. In one embodiment of the invention, a cooling plate is optimized to have a dielectric constant of approximately 10. In one embodiment of the invention, a cooling plate is optimized to have a low electrical conductivity. In one embodiment of the invention, a cooling plate is optimized to have an electrical conductivity of less than 0.5 siemens per meter. In one embodiment of the invention, a cooling plate is optimized to have a high thermal conductivity. In one embodiment of the invention, a cooling plate is optimized to have a thermal conductivity of between 18 and 50 Watts per meter-Kelvin at room temperature. In one embodiment of the invention, a cooling plate is optimized to have a thermal conductivity of between 10 and 100 Watts per meter-Kelvin at room temperature. In one embodiment of the invention, a cooling plate is optimized to have a thermal conductivity of between 0.1 and 5 Watts per meter-Kelvin at room temperature. In one embodiment of the invention, a cooling plate is comprised, at least in part, of a ceramic material. In one embodiment of the invention, a cooling plate is comprised, at least in part, of alumina. 
     In one embodiment of the invention, a cooling plate may be, for example, a thin film polymer material. In one embodiment of the invention, a cooling plate may be, for example, a polyimide material. In one embodiment of the invention, a cooling plate may be, for example, a material having a conductivity of approximately 0.12 Watts per meter-Kelvin and a thickness of between approximately 0.002″ and 0.010″. 
     Cooling Chamber 
     In one embodiment of the invention, a cooling chamber has a thickness which is optimized for the electromagnetic radiation frequency, cooling fluid composition and cooling plate composition. In one embodiment of the invention, a cooling chamber has a thickness which is optimized for a high dielectric cooling fluid. In one embodiment of the invention, a cooling chamber has a thickness which is optimized for a cooling fluid having a dielectric constant of approximately 80, such as, for example, de-ionized water. In one embodiment of the invention, a cooling chamber has a thickness of between 0.5 and 1.5 millimeters. In one embodiment of the invention, a cooling chamber has a thickness of approximately 1.0 millimeters. In one embodiment of the invention, a cooling chamber has a thickness which is optimized for a low dielectric cooling fluid. In one embodiment of the invention, a cooling chamber has a thickness which is optimized for a cooling fluid which has a dielectric constant of approximately 2, such as, for example, vegetable oil. Low dielectric, low conductivity cooling fluids may be advantageous where it is desirable to limit the losses or to match elements. In one embodiment of the invention, a cooling chamber is optimized such that eddy currents are minimized as fluid flows through the cooling chamber. In one embodiment of the invention, a cooling chamber is optimized such that air bubbles are minimized as fluid flows through the cooling chamber. In one embodiment of the invention, field spreaders located in the cooling chamber are positioned and designed to optimize laminar flow of cooling fluid through the cooling chamber. In one embodiment of the invention, field spreaders located in the cooling chamber are substantially oval in shape. In one embodiment of the invention, field spreaders located in the cooling chamber are substantially round in shape. In one embodiment of the invention, field spreaders located in the cooling chamber are substantially rectangular in shape. 
     Thermoelectric Module 
     In one embodiment of the invention, a cooling system optimized to maintain the skin surface at a predetermined temperature may be, for example a thermoelectric module. In one embodiment of the invention, a cooling system is optimized to maintain the skin surface at a predetermined temperature by attaching the cold plate side of a thermoelectric cooler(s) (TEC) to a face of the cooling plate adjacent to the waveguide antenna(s). The hot side of the TEC(s) is attached to a finned heat sink(s) that is acted upon by an axial fan(s) in order to maintain the hot side of the TEC(s) at a low temperature to optimize the cooling performance of the TEC(s). The attachment of the TEC(s) to the cooling plate and heat sink(s) utilizes ceramic thermal adhesive epoxy. For example, the TEC(s) may be part number 06311-5L31-03CFL, available from Custom Thermoelectric, the heat sink(s) may be part number 655-53AB, available from Wakefield Engineering, the ceramic thermal adhesive epoxy may be available from Arctic Silver and the axial fans(s) may be part number 1608KL-04W-B59-L00 available from NMB-MAT. 
     In one embodiment of the invention, a cooling system is optimized to maintain the skin surface at a predetermined temperature by constructing the cold plate side of a thermoelectric cooler(s) (TEC) as the cooling plate adjacent to or surrounding the waveguide antenna(s) with an opening(s) in the hot side of the TEC(s) where the waveguide antenna(s) exist. The hot side of the TEC(s) is attached to a finned heat sink(s) that is acted upon by an axial fan(s) in order to maintain the hot side of the TEC(s) at a low temperature to optimize the cooling performance of the TEC(s). The attachment of the TEC(s) to the heat sink(s) utilizes ceramic thermal adhesive epoxy. For example, the TEC(s) may be available from Laird Technology, the heat sink(s) may be part number 655-53AB, available from Wakefield Engineering, the ceramic thermal adhesive epoxy may be available from Arctic Silver and the axial fans(s) may be part number 1608KL-04W-B59-L00 available from NMB-MAT. 
     In one embodiment of the invention, a cooling system is optimized to maintain the skin surface at a predetermined temperature by attaching the cold plate side of a thermoelectric cooler(s) (TEC) to a side(s) of the waveguide antenna(s). The hot side of the TEC(s) is attached to a finned heat sink(s) that is acted upon by an axial fan(s) in order to maintain the hot side of the TEC(s) at a low temperature to optimize the cooling performance of the TEC(s). The attachment of the TEC(s) to the waveguide antenna(s) and heat sink(s) utilizes ceramic thermal adhesive epoxy. For example, the TEC(s) may be part number 06311-5L31-03CFL, available from Custom Thermoelectric, the heat sink(s) may be part number 655-53AB, available from Wakefield Engineering, the ceramic thermal adhesive epoxy may be available from Arctic Silver and the axial fans(s) may be part number 1608KL-04W-B59-L00 available from NMB-MAT. 
     Energy 
     In one embodiment of the invention, energy is delivered to the skin for a period of time which optimizes the desired tissue effect. In one embodiment of the invention, energy is delivered to the skin for a period of between 3 and 4 seconds. In one embodiment of the invention, energy is delivered to the skin for a period of between 1 and 6 seconds. In one embodiment of the invention, energy is delivered to a target region in tissue. In one embodiment of the invention energy delivered to the target region for a time sufficient to result in an energy density at the target tissue of between 0.1 and 0.2 Joules per cubic millimeter. In one embodiment of the invention energy delivered to the target region for a time sufficient to heat the target tissue to a temperature of at least 75° C. In one embodiment of the invention energy delivered to the target region for a time sufficient to heat the target tissue to a temperature of between 55 and 75° C. In one embodiment of the invention energy delivered to the target region for a time sufficient to heat the target tissue to a temperature of at least 45° C. 
     Cooling 
     In one embodiment of the invention, the skin surface is cooled for a period of time which optimizes the desired tissue effect. In one embodiment of the invention, the skin surface is cooled during the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of time prior to the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of between 1 and 5 seconds prior to the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of approximately 2 seconds prior to the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of time after to the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of between 10 and 20 seconds after the time energy is delivered to the skin. In one embodiment of the invention, the skin surface is cooled for a period of approximately 20 seconds after the time energy is delivered to the skin. 
     Output Power 
     In one embodiment of the invention, power is delivered to a device adapted to radiate electromagnetic energy. In one embodiment of the invention, power is delivered to an input to an antenna, such as, for example, the feed to a waveguide antenna. In one embodiment of the invention, the power available at the antenna&#39;s input port is between 50 and 65 Watts. In one embodiment of the invention, the power available at the antenna&#39;s input port is between 40 and 70 Watts. In one embodiment of the invention, power available at the antenna&#39;s input port varies over time. 
     Tissue Acquisition 
     In one embodiment of the invention, skin is held in an optimal position with respect to an energy delivery device. In one embodiment of the invention, skin is held in an optimal position with respect to an energy delivery device using vacuum pressure. In one embodiment of the invention, skin is held in an optimal position with respect to an energy delivery device using vacuum pressure of between 400 and 750 millimeters of mercury. In one embodiment of the invention, skin is held in an optimal position with respect to an energy delivery device using vacuum pressure of approximately 650 millimeters of mercury. Other tissue acquisition systems, methods, and devices that can be used with embodiments of the invention to hold the skin in place and/or protect non-target tissue structures can be found, for example, at FIGS. 38-52C and pp. 46-57 of U.S. Provisional App. No. 60/912,899; and FIGS. 12-16B and pp. 24-29 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described, for example, in FIGS. 38-52C and pp. 46-55 of Appendix 1 and FIGS. 12-16B and pp. 29-33 of Appendix 2. 
     Tissue Interface 
     Tissue Chamber 
     In one embodiment of the invention, a tissue chamber may be, for example, a suction chamber. In one embodiment of the invention, a tissue chamber may be configured to acquire at least a portion of the skin tissue. In one embodiment of the invention, a tissue chamber may be operatively coupled to a vacuum source. In one embodiment of the invention, a tissue chamber may be configured with at least one tapered wall. In one embodiment of the invention, a tissue chamber may be configured to at least partially acquire skin tissue and bring skin tissue in contact with cooling plate. In one embodiment of the invention, tissue chamber may be configured to include at least one suction element. In one embodiment of the invention, tissue chamber may be configured to elevate skin and placing skin in contact with a cooling element. In one embodiment of the invention, tissue chamber may be configured to elevate skin and placing skin in contact with a cooling element. In one embodiment of the invention, tissue chamber may be configured to elevate skin and placing skin in contact with a suction chamber. In one embodiment of the invention, tissue chamber may be configured to elevate skin and placing skin in contact with suction openings. In one embodiment of the invention, suction openings may include at least one channel wherein the channel may have rounded edges. In one embodiment of the invention, tissue chamber may have an ovoid or racetrack shape wherein the tissue chamber includes straight edges perpendicular to direction of cooling fluid flow. In one embodiment of the invention, tissue chamber may be configured to elevate skin separating skin tissue from underlying muscle tissue. In one embodiment of the invention, tissue chamber may be configured to include at least one temperature sensor. In one embodiment of the invention, tissue chamber may be configured to include at least one temperature sensor wherein the temperature sensor may be a thermocouple. In one embodiment of the invention, tissue chamber may be configured to include at least one temperature sensor wherein the temperature sensor is configured to monitor the temperature at skin surface. In one embodiment of the invention, tissue chamber may be configured to include at least one temperature sensor wherein the temperature sensor is configured such that it does not significantly perturb a microwave signal. 
     In one embodiment of the invention, a tissue interface may comprise a tissue chamber which is optimized to separate skin from underlying muscle. In one embodiment of the invention, a tissue interface may comprise a vacuum chamber which is optimized to separate skin from underlying muscle when skin is pulled into a tissue chamber by, for example, vacuum pressure. In one embodiment of the invention, a tissue chamber may be optimized to have a depth of between approximately 1 millimeter and approximately 30 millimeters. In one embodiment of the invention, a tissue chamber may be optimized to have a depth of approximately 7.5 millimeters. In one embodiment of the invention, walls of a tissue chamber may be optimized to have an angle of between approximately 2 and 45 degrees. In one embodiment of the invention, walls of a tissue chamber may be optimized to have a chamber angle Z of between approximately 5 and 20 degrees. In one embodiment of the invention, walls of a tissue chamber may be optimized to have a chamber angle Z of approximately 20°. In one embodiment of the invention, a tissue chamber may be optimized to have an ovoid shape. In one embodiment of the invention, a tissue chamber may be optimized to have a racetrack shape. In one embodiment of the invention, a tissue chamber may be optimized to have an aspect ratio wherein the aspect ratio may be defined as the minimum dimension of a tissue interface surface to the height of the vacuum chamber. In the embodiment of the invention illustrated in  FIG. 8 , the aspect ratio may be, for example the ratio between minimum dimension 10 and tissue depth Y. In one embodiment of the invention, a tissue chamber may be optimized to have an aspect ratio of between approximately 1:1 and approximately 3:1. In one embodiment of the invention, a tissue chamber may be optimized to have an aspect ratio of approximately 2:1. 
     Staged Treatments 
     In some embodiments, it may be desirable to perform the treatment in stages. Additionally, the treatment may be patterned such that sections of target tissue are treated in the initial stage while other sections are treated in subsequent stages. Treatments using systems and devices disclosed herein may, for example, be treated in stages as disclosed in, for example, at FIGS. 54-57 and pp. 61-63 of U.S. Provisional App. No. 60/912,899; and FIGS. 17-19 and pp. 32-34 of U.S. Provisional App. No. 61/013,274 both incorporated by reference in their entireties, as well as illustrated and described, for example, in FIGS. 54-57 and pp. 58-60 of Appendix 1 and FIGS. 17-19 and pp. 36-38 of Appendix 2. 
     Diagnosis 
     Embodiments of the present invention also include methods and apparatuses for identifying and diagnosing patients with hyperhidrosis. Such diagnosis can be made based on subjective patient data (e.g., patient responses to questions regarding observed sweating) or objective testing. In one embodiment of objective testing, an iodine solution can be applied to the patient to identify where on a skin surface a patient is sweating and not sweating. Moreover, particular patients can be diagnosed based on excessive sweating in different parts of the body in order to specifically identify which areas to be treated. Accordingly, the treatment may be applied only selectively to different parts of the body requiring treatment, including, for example, selectively in the hands, armpits, feet and/or face. 
     Quantifying Treatment Success 
     Following completion of any of the treatments described above, or any stage of a treatment, the success can be evaluated qualitatively by the patient, or may be evaluated quantitatively by any number of ways. For example, a measurement can be taken of the number of sweat glands disabled or destroyed per surface area treated. Such evaluation could be performed by imaging the treated area or by determining the amount of treatment administered to the treated area (e.g., the quantity of energy delivered, the measured temperature of the target tissue, etc.). The aforementioned iodine solution test may also be employed to determine the extent of treatment effect. In addition, a treatment can be initiated or modified such that the amount of sweating experienced by a patient may be reduced by a desired percentage as compared to pre-treatment under defined testing criteria. For example, for a patient diagnosed with a particularly severe case of hyperhidrosis, the amount of sweating may be reduced by about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or more. For a patient diagnosed with a less severe or more normal sweating profile, a step-wise reduction of sweating may be achieved, but with less resolution. For example, such a patient may only be able to achieve partial anhidrosis in 25% increments. 
     Overview of Systems, Methods, and Devices 
     In one embodiment of the invention, a method of applying energy to tissue is described. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high power loss density in skin. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high power loss density in a region of the dermis adjacent a critical interface. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high power loss density in a glandular layer. In one embodiment of the invention, the method includes the step of generating a radiation pattern in skin with first and second regions of localized high power loss density wherein the first and second regions are separated by a region of low power loss density. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized high power loss density in skin wherein the first and second regions are separated by a region of low power loss density. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized high power loss density in skin wherein adjacent regions of high power loss density are separated by regions of low power loss density. 
     In one embodiment of the invention, a method of applying energy to tissue is described. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high specific absorption rate (SAR) in skin. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high specific absorption rate (SAR) in a region of the dermis adjacent a critical interface. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high specific absorption rate (SAR) in a glandular layer. In one embodiment of the invention, the method includes the step of generating a radiation pattern in skin with first and second regions of localized specific absorption rate (SAR) wherein the first and second regions are separated by a region of low specific absorption rate (SAR). In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized high specific absorption rate (SAR) in skin wherein the first and second regions are separated by a region of low specific absorption rate (SAR). In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized specific absorption rate (SAR) in skin wherein adjacent regions of high specific absorption rate (SAR) are separated by regions of low specific absorption rate (SAR). 
     In one embodiment of the invention, a method of applying energy to tissue is described. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high temperature in skin. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high temperature in a region of the dermis adjacent a critical interface. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a region of localized high temperature in a glandular layer. In one embodiment of the invention, the method includes the step of generating a radiation pattern in skin with first and second regions of localized temperature wherein the first and second regions are separated by a region of low temperature. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized high temperature in skin wherein the first and second regions are separated by a region of low temperature. In one embodiment of the invention, the method includes the step of generating a radiation pattern with a plurality of regions of localized temperature in skin wherein adjacent regions of high temperature are separated by regions of low temperature. 
     In one embodiment of the invention, a method of aligning electromagnetic field to preferentially treat tissue having a relatively high water content is described. In one embodiment of the invention, the method includes the steps of irradiating tissue with an electromagnetic Electric field aligned with a surface of the skin. In one embodiment of the invention, the method includes irradiating tissue with electromagnetic radiation in the TE 10  mode. In one embodiment of the invention, the method includes irradiating tissue with electromagnetic radiation having a minimal E-field in a direction perpendicular to at least a portion of a skin surface. In one embodiment of the invention, the method includes aligning an E-field component of an electromagnetic wave to preferentially heat tissue having a high water content by irradiating with transverse electric (TE) or transverse electromagnetic (TEM) waves. 
     In one embodiment of the invention, a method for controlling the delivery of energy to tissue is described. In one embodiment of the invention, the method of delivering energy includes the step of delivering energy at a frequency of approximately 5.8 GHz. In one embodiment of the invention, the method of delivering energy includes the step of delivering energy having a power of greater than approximately 40 Watts. In one embodiment of the invention, the method of delivering energy includes the step of delivering energy for a period of between approximately 2 seconds and approximately 10 seconds. In one embodiment of the invention, the method of delivering energy includes the step of pre-cooling skin surface for a period of approximately 2 seconds. In one embodiment of the invention, the method of delivering energy includes the step of post cooling for a period of approximately 20 seconds. In one embodiment of the invention, the method of delivering energy includes the step of maintaining tissue engagement for a period of more than approximately 22 seconds. In one embodiment of the invention, the method of delivering energy includes the step of engaging tissue using a vacuum pressure of approximately 600 millimeters of mercury. In one embodiment of the invention, the method of delivering energy includes the step of measuring skin temperature. In one embodiment of the invention, the method of delivering energy includes the step of adjusting energy delivery duration; pre-cooling duration; post-cooling duration; output power; frequency; vacuum pressure as a result of feedback of tissue parameters such as, for example, skin temperature. In one embodiment of the invention, the method of delivering energy includes the step of adjusting energy delivery duration; pre-cooling duration; post-cooling duration; output power; frequency; vacuum pressure as a result of feedback of tissue parameters such as, for example, cooling fluid temperature. 
     In one embodiment of the invention, a method of removing heat from tissue is described. In one embodiment of the invention, a method of cooling tissue is described, the method including engaging the surface of the skin. In one embodiment of the invention, the method includes the step of positioning a cooling element in contact with the skin surface. In one embodiment of the invention, the method includes the step of conductively cooling the skin surface. In one embodiment of the invention, the method includes the step of convectively cooling the skin surface. In one embodiment of the invention, the method includes the step of conductively and convectively cooling the skin surface 
     In one embodiment of the invention, a method of damaging or destroying tissue structures is described. In one embodiment of the invention, a method of damaging or destroying glands is described. In one embodiment of the invention the method includes the step of inducing hyperthermia in the tissue structures. In one embodiment of the invention, hyperthermia may be accomplished by mild heating of tissue to a temperature of, for example, between approximately 42° C. and 45° C. In one embodiment of the invention the method includes the step of ablating tissue structures may be accomplished by heating of tissue to temperatures in excess of approximately 47° C. 
     In one embodiment of the invention a method of treating tissue using electromagnetic radiation is described. In one embodiment of the invention a method of treating tissue includes creating a secondary effect in tissue. In one embodiment of the invention a method of treating tissue includes creating a secondary effect in tissue wherein the secondary effect includes, for example, reducing bacterial colonization. In one embodiment of the invention a method of treating tissue includes creating a secondary effect in tissue wherein the secondary effect includes clearing or reducing skin blemishes. In one embodiment of the invention a method of treating tissue includes creating a secondary effect in tissue wherein the secondary effect includes clearing or reducing skin blemishes resulting from, for example, acne vulgaris. In one embodiment of the invention a method of treating tissue includes damaging sebaceous glands. In one embodiment of the invention a method of treating tissue includes disabling sebaceous glands. In one embodiment of the invention a method of treating tissue includes temporarily disabling sebaceous glands. 
     In one embodiment of the invention, a method of delivering energy to selected tissue is described. In one embodiment of the invention, the method includes delivering energy via a microwave energy delivery applicator. In one embodiment of the invention, the method involves delivering energy sufficient to create a thermal effect in a target tissue within the skin tissue. In one embodiment of the invention, the method includes the step of delivering energy to tissue which is subject to dielectric heating. In one embodiment of the invention, the method includes the step of delivering energy to tissue having a high dielectric moment. In one embodiment of the invention, the method includes delivering energy to target tissue within the skin tissue selected from the group consisting of collagen, hair follicles, cellulite, eccrine glands, apocrine glands, sebaceous glands, spider veins and combinations thereof. In one embodiment of the invention, target tissue within the skin tissue comprises the interface between the dermal layer and subcutaneous layer of the skin tissue. In one embodiment of the invention, creating a thermal effect in the target tissue comprises thermal alteration of at least one sweat gland. In one embodiment of the invention, creating a thermal effect in the target tissue comprises ablation of at least one sweat gland. 
     In one embodiment of the invention, a method of delivering microwave energy to tissue is described. In one embodiment of the invention, the method includes the step of applying a cooling element to the skin tissue. In one embodiment of the invention, the method includes the step of applying microwave energy to tissue at a power, frequency and duration and applying cooling at a temperature and a duration sufficient to create a lesion proximate interface between the dermis layer and subcutaneous layer in the skin tissue while minimizing thermal alteration to non-target tissue in the epidermis and dermis layers of the skin tissue. In one embodiment of the invention, the method includes the step of applying microwave energy to a second layer of skin containing sweat glands sufficient to thermally alter the sweat glands. In one embodiment of the invention, the method includes the step of applying microwave energy while the first layer of skin is protectively cooled, the second layer being deeper than the first layer relative to the skin surface. In one embodiment of the invention, the method includes the step of cooling via a cooling element. 
     In one embodiment of the invention, the method includes the step of using one or more field spreaders to spread the MW energy as it emerges from an antenna. In one embodiment of the invention, the method includes creating a contiguous lesion larger than a single waveguide lesion. In one embodiment of the invention, the method includes the step of using multiple antennas. In one embodiment of the invention, the method includes the step of creating a contiguous lesion larger than a single waveguide lesion. In one embodiment of the invention, the method includes the step of using an array of waveguides. In one embodiment of the invention, the method includes the step of activating a plurality of waveguides in series. In one embodiment of the invention, the method includes the step of activating multiple antennas. In one embodiment of the invention, the method includes the step of activating less than all antennas in an array. In one embodiment of the invention, the method includes the step of continuously cooling under all antennas in an array. 
     In one embodiment of the invention, a method of applying energy to tissue is described. In one embodiment of the invention, the method includes the step of applying energy at a depth deeper than a skin surface. In one embodiment of the invention, the method includes the step of applying energy but not as deep as nerve or muscle tissue. In one embodiment of the invention, the method includes the step of applying electromagnetic radiation at a frequency which concentrates energy at target tissue 
     In one embodiment of the invention, a method of selectively heating tissue is described. In one embodiment of the invention, the method includes the step of selectively heating tissue by dielectric heating. In one embodiment of the invention, the method includes the step of selectively heating glands. In one embodiment of the invention, the method includes the step of selectively heating glandular fluid. In one embodiment of the invention, the method includes the step of heating tissue to a temperature sufficient to damage a gland. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to result in morbidity. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to result in death. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to damage adjacent hair follicles. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to destroy adjacent hair follicles. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to induce hyperthermia in tissue at the skin/fat interface. In one embodiment of the invention, the method includes the step of heating the gland to a temperature sufficient to induce hyperthermia in tissue at the skin/fat interface while minimizing hyperthermia in surrounding tissue. In one embodiment of the invention, the method includes the step of heating the gland to at least 50° C. 
     In one embodiment of the invention, a method of generating a temperature profile in skin tissue is described. In one embodiment of the invention the method includes generating a temperature profile having a peak in region directly above skin-fat interface. In one embodiment of the invention, the method includes the step of generating a temperature profile wherein the temperature declines towards the skin surface. In one embodiment of the invention, the method includes the step of generating a temperature profile wherein the temperature declines towards the skin surface in the absence of cooling. 
     In one embodiment of the invention, a method of positioning skin is described. In one embodiment of the invention, the method includes the step of using suction, pinching or adhesive. In one embodiment of the invention, the method includes the step of using suction, pinching or adhesive to lift a dermal and subdermal layer away from a muscle layer. 
     In one embodiment of the invention, a method of applying energy to tissue is described. In one embodiment of the invention, the method includes the step of placing a microwave energy delivery applicator over the skin tissue. In one embodiment of the invention, the microwave applicator includes a microwave antenna. In one embodiment of the invention, the microwave antenna is selected from the group consisting of: single slot, multiple slot, waveguide, horn, printed slot, patch, Vivaldi antennas and combinations thereof. In one embodiment of the invention, the method includes the step of positioning the microwave energy delivery applicator over a region having more absorptive tissue elements. In one embodiment of the invention, the method includes the step of positioning the microwave energy delivery applicator over a region having a concentration of sweat glands. In one embodiment of the invention, the method includes the step of positioning the microwave energy delivery applicator over a hair bearing area. In one embodiment of the invention, the method includes the step of positioning the microwave energy delivery applicator over an axilla. In one embodiment of the invention, the method includes the step of acquiring skin within a suction chamber. In one embodiment of the invention, the method includes the step of activating a vacuum pump. In one embodiment of the invention, the method includes the step of deactivating a vacuum pump to release skin. In one embodiment of the invention, the method includes the step of securing skin tissue proximate to the microwave energy delivery applicator. In one embodiment of the invention, the method includes the step of securing skin tissue proximate to the microwave energy delivery applicator by applying suction to the skin tissue. In one embodiment of the invention, the method includes the step of securing skin tissue proximate to the microwave energy delivery applicator includes the step of at least partially acquiring the skin tissue within a suction chamber adjacent to the energy delivery applicator. In one embodiment of the invention, the method includes the step of using a lubricant to enhance vacuum. In one embodiment of the invention, the method includes the step of securing skin tissue proximate to the microwave energy delivery applicator includes the step of elevating the skin tissue. In one embodiment of the invention, the method includes the step of securing skin tissue proximate to the microwave energy delivery applicator includes the step of brining skin in contact with cooling. In one embodiment of the invention, the method includes the step of activating a vacuum pump to acquire the skin within a suction chamber. 
     In one embodiment, disclosed herein is a system for the application of microwave energy to a tissue, including a signal generator adapted to generate a microwave signal having predetermined characteristics; an applicator connected to the generator and adapted to apply microwave energy to tissue, the applicator comprising one or more microwave antennas and a tissue interface; a vacuum source connected to the tissue interface; a cooling source connected to said tissue interface; and a controller adapted to control the signal generator, the vacuum source, and the coolant source. In some embodiments, the microwave signal has a frequency in the range of between about 4 GHz and about 10 GHz, between about 5 GHz and about 6.5 GHz, or about 5.8 GHz. The system can further comprise an amplifier connected between the signal generator and the applicator. The microwave antenna may comprise an antenna configured to radiate electromagnetic radiation polarized such that an E-field component of the electromagnetic radiation is substantially parallel to an outer surface of the tissue. In some embodiments, the microwave antenna comprises a waveguide antenna. The antenna may comprise an antenna configured to radiate in TE10 mode, and/or TEM mode. The tissue interface can be configured to engage and hold skin. The skin is of the axillary region in some embodiments. The microwave antenna may comprise an antenna configured to radiate electromagnetic radiation polarized such that an E-field component of the electromagnetic radiation is parallel to an outer surface of the tissue. 
     In some embodiments, the tissue interface comprises a cooling plate and a cooling chamber positioned between the cooling plate and the microwave antenna. In some embodiments, the cooling plate has a dielectric constant between about 2 and 15. The vacuum source can be configured to supply vacuum pressure to the tissue interface. In some embodiments, the vacuum pressure is between about 400 mmHg to about 750 mmHg, or about 650 mmHg in some embodiments. The cooling source can be configured to supply a coolant to the tissue interface. The coolant can be a cooling fluid, which in some embodiments has a dielectric constant of between about 70 and 90, about 80, between about 2 and 10, or about 2. In some embodiments, the cooling fluid can have a temperature of between about −5° C. and 40° C., 10° C. and 25° C., or about 22° C. In some embodiments, the cooling fluid has a flow rate through at least a portion of the tissue interface of between about 100 mL and 600 mL per second, or between about 250 mL and 450 mL per second. In some embodiments, the cooling fluid is configured to flow through the tissue interface at a velocity of between 0.18 and 0.32 meters per second. The cooling fluid can be selected from, e.g., glycerin, vegetable oil, isopropyl alcohol, water, water mixed with alcohol, or other combinations in some embodiments. The cooling source may comprise a thermoelectric module. In some embodiments, the tissue comprises a first layer and a second layer, the second layer below the first layer, wherein the controller is configured such that the system delivers energy such that a peak power loss density profile is created in the second layer. 
     In another embodiment, disclosed is an apparatus for delivering microwave energy to target tissue, the apparatus comprising a tissue interface; a microwave energy delivery device; a cooling element positioned between the tissue interface and the microwave energy device, the cooling element comprising a cooling plate positioned at the tissue interface; and a cooling fluid positioned between the cooling element and the microwave delivery device, the cooling fluid having a dielectric constant greater than a dielectric constant of the cooling element. In some embodiments, the tissue interface comprises a tissue acquisition chamber, which can be a vacuum chamber in some embodiments. The cooling plate may be made of ceramic. In some embodiments, the cooling plate is configured to contact a skin surface about the target tissue, cool the skin tissue, and physically separate the skin tissue from the cooling fluid. In some embodiments, the microwave energy delivery device comprises a microwave antenna, which may be a waveguide antenna in some embodiments. 
     In another embodiment, disclosed is an apparatus for delivering microwave energy to a target region in tissue, the apparatus comprising: a tissue interface having a tissue acquisition chamber; a cooling element having a cooling plate; and a microwave energy delivery device having a microwave antenna. In some embodiments, the tissue acquisition chamber comprises a vacuum chamber adapted to elevate tissue, including the target region, and bring the tissue in contact with the cooling element. In some embodiments, the vacuum chamber has a racetrack shape comprising a first side and a second side, the first and second sides parallel to each other, and a first end and a second end, the first and second ends having arcuate shapes. In some embodiments, the cooling plate is configured to contact a skin surface above the target tissue, cool the skin tissue, and physically separate the skin tissue from the microwave energy delivery device. The cooling plate may be substantially transparent to microwave energy. In some embodiments, the microwave antenna is configured to deliver sufficient energy to the target region to create a thermal effect. In some embodiments, the microwave antenna comprises a waveguide antenna. 
     Also disclosed, in one embodiment, is an apparatus for delivering microwave energy to a target region in tissue, the apparatus comprising a vacuum chamber adapted to elevate tissue including the target region and bring the tissue into contact with a cooling plate, wherein the cooling plate is adapted to contact a skin surface above the target region, cool the skin surface, and physically separate the skin tissue from the microwave energy delivery device; and a microwave antenna configured to deliver sufficient energy to the target region to create a thermal effect. In some embodiments, the vacuum chamber may have a race track shape comprising a first side and a second side, the first and second sides parallel to each other; and a first end and a second end, the first and second ends having arcuate shapes. In some embodiments, the cooling plate is substantially transparent to microwave energy. In some embodiments, the microwave antenna is configured to deliver sufficient energy to the target region to create a thermal effect. In some embodiments, the microwave antenna comprises a waveguide antenna. In some embodiments, the microwave antenna is configured to generate a radiation pattern having a peak at the target region. 
     Also disclosed, in one embodiment, is a system for coupling microwave energy into tissue, the system comprising a microwave antenna, a fluid chamber positioned between the microwave antenna and the tissue, and a cooling plate positioned between the cooling chamber and the tissue. In one embodiment, the system further comprises at least one field spreader. The field spreader may be positioned within the fluid chamber between the waveguide and the cooling plate. The field spreader may be configured to facilitate laminar flow of fluid through the fluid chamber. In one embodiment, the field spreader may be configured to prevent one or more of eddy currents or air bubbles within the cooling fluid. In one embodiment, the system may further comprise a cooling fluid selected to maximize thermal transfer while minimizing microwave reflections. The cooling fluid may be selected from the group consisting of alcohol, glycerol, ethylene glycol, deionized water, a germicide, and vegetable oil. In one embodiment, the microwave antenna may a waveguide including a dielectric filler selected to generate a field having a minimal electric field perpendicular to a surface of the tissue at a predetermined frequency. In one embodiment, the fluid chamber has a shape configured to facilitate laminar flow of cooling fluid therethrough. The fluid chamber may be rectangular shaped. In some embodiments, the cooling plate is thermally conductive and substantially transparent to microwave energy. 
     In another embodiment, a method of creating a tissue effect in a target tissue layer is disclosed, comprising the steps of: irradiating the target tissue layer and a first tissue layer through a skin surface with electromagnetic energy having predetermined frequency and electric field characteristics, wherein the first tissue layer is above the target tissue layer, the first tissue layer being adjacent to a surface of the skin; and generating a power loss density profile, wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In one embodiment, the method further comprises the step of identifying a patient desiring a reduction in sweat production. In other embodiments, the method further comprises the step of identifying a patient desiring a reduction in cellulite, identifying a patient with hyperhidrosis, identifying a patient with telangiectasias, identifying a patient with varicose veins, or identifying a patient desiring hair removal. In another embodiment, the method further comprises the step of removing heat from the first tissue layer. In one embodiment, the method further comprises the step of removing heat from the tissue layer. In one embodiment, the tissue effect comprises a lesion. The lesion may have an origin in the target tissue layer. In one embodiment, the origin of the lesion is in the region of the target tissue layer having the peak power loss density. In one embodiment, the method further comprises the step of removing sufficient heat from the first layer to prevent the lesion from growing into the first layer, wherein the step of removing heat from the first tissue layer comprises cooling the skin surface. In one embodiment, the target tissue layer may comprise the dermis, a deep layer of the dermis, or a glandular layer. In one embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface. The electromagnetic energy may have an electric field component which is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range between about 4 GHz and 10 Ghz, between 5 GHz and 6.5 GHz, or approximately 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. In one embodiment, the standing wave pattern has a constructive interference peak in the region of the target tissue layer. The standing wave pattern may have a constructive interference minimum in the first tissue layer. 
     In another embodiment, disclosed is a method of creating a lesion in a target tissue layer in the absence of cooling, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent to a skin surface, the method comprising the steps of: irradiating the target tissue layer and a first tissue layer through a skin surface with electromagnetic energy having predetermined frequency and electric field characteristics, wherein the first tissue layer is above the target tissue layer, the first tissue layer being adjacent to a surface of the skin; and generating a power loss density profile, wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In one embodiment, the lesion has an origin in the target tissue layer. In some embodiments, the target tissue layer comprises the dermis, a deep layer of the dermis, or a glandular layer. In one embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface. In one embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface. In one embodiment, the electromagnetic energy has an electric field component which is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or a TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz, or approximately 5.8 GHz. The electromagnetic energy may generate heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. The standing wave pattern may have a constructive interference peak in the region of the target tissue layer or in the first tissue layer. In one embodiment, the origin of the lesion is in the region of the target tissue layer having the peak power loss density. 
     In another embodiment, disclosed is a method of generating heat in a target tissue layer wherein the heat is sufficient to create a lesion in or proximate to the target tissue layer, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent to a skin surface, the method comprising the steps of: irradiating the target tissue layer and the first tissue layer through the skin surface with electromagnetic energy having predetermined frequency and electric field characteristics; and generating a power loss density profile wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In one embodiment, the lesion has an origin in the target tissue layer. In some embodiment, the target tissue layer comprises the dermis, a deep layer of the dermis or a glandular layer. In one embodiment, the method further comprises the step of removing heat from the first tissue layer. In one embodiment, the method further comprises the step of removing sufficient heat from the first layer to prevent the lesion from growing into the first layer, wherein the step of removing heat from the first tissue layer comprises cooling the skin surface. In some embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface, while in other embodiments, the electric field component is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz, or approximately 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. In some embodiments, the standing wave pattern has a constructive interference peak in the region of the target tissue layer or in the first tissue layer. In one embodiment, the origin of the lesion is in the region of the target tissue layer having the peak power loss density. In one embodiment, the heat is sufficient to destroy bacteria within the target tissue. In some embodiments, the method further comprises the step of identifying a patient with acne or identifying a patient desiring a reduction of sweat production. 
     In another embodiment, disclosed is a method of generating heat in a target tissue layer in the absence of cooling wherein the heat is sufficient to create a tissue effect in or proximate to the target tissue layer, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent to a skin surface, the method comprising the steps of: irradiating the target tissue layer and the first tissue layer through the skin surface with electromagnetic energy having predetermined frequency and electric field characteristics; and generating a power loss density profile wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In one embodiment, the heat is sufficient to generate a lesion having an origin in the target tissue layer. In some embodiments, the target tissue layer comprises the dermis, deep layer of the dermis or glandular layer. In one embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface, while in another embodiment, the electric field component is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or a TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz, or about 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. In some embodiments, the standing wave pattern has a constructive interference peak in the region of the target tissue layer or in the first tissue layer. In one embodiment, the standing wave pattern has a constructive interference minimum in the first tissue layer. In one embodiment, the origin of the lesion is in the region of the target tissue layer having the peak power loss density. 
     Also disclosed herein, in another embodiment is a method of generating a temperature profile in tissue wherein the temperature profile has a peak in a target tissue layer, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent to a skin surface, the method comprising the steps of: irradiating the target tissue layer and the first tissue layer through the skin surface with electromagnetic energy having predetermined frequency and electric field characteristics; and generating a power loss density profile wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In some embodiments, the target tissue layer comprises the dermis, a deep layer of the dermis or a glandular layer. In one embodiment, the method further comprises the step of removing heat from the first tissue layer. In one embodiment, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface. In one embodiment, the electromagnetic energy has an electric field component which is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, between about 5 GHz and 6.5 GHz, or of approximately 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. The standing wave pattern may have a constructive interference peak in the region of the target tissue layer. The standing wave pattern may have a constructive interference minimum in the first tissue layer. In one embodiment, the peak temperature is in the region of the target tissue layer having the peak power loss density. 
     In another embodiment, disclosed herein is a method of generating a temperature profile in tissue in the absence of cooling wherein the temperature profile has a peak in a target tissue layer, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent to a skin surface, the method comprising the steps of: irradiating the target tissue layer and the first tissue layer through the skin surface with electromagnetic energy having predetermined frequency and electric field characteristics; and generating a power loss density profile wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In some embodiments, the target tissue layer comprises the dermis, a deep layer of the dermis or a glandular layer. In some embodiments, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface or which is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or a TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz or approximately 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. The standing wave pattern may have a constructive interference peak in the region of the target tissue layer. The standing wave pattern may have a constructive interference minimum in the first tissue layer. In one embodiment, the peak temperature is in the region of the target tissue layer having the peak power loss density. 
     In another embodiment, disclosed is a method of creating a lesion in a first layer of tissue, the first layer having an upper portion adjacent an external surface of the skin and a lower portion adjacent a second layer of the skin, the method comprising the steps of: exposing the external surface of the skin to microwave energy having a predetermined power, frequency, and electric field orientation; generating an energy density profile having a peak in the lower portion of the first layer; and continuing to expose the external surface of the skin to the microwave energy for a time sufficient to create a lesion, wherein the lesion begins in the peak energy density region. In one embodiment, the first layer of skin has a first dielectric constant and the second layer of skin has a second dielectric constant, wherein the first dielectric constant is greater than the second dielectric constant. In one embodiment, the first layer has a dielectric constant greater than about 25 and the second layer has a dielectric constant less than or equal to about 10. In one embodiment, the first layer comprises at least a portion of a dermis layer. In some embodiments, the second layer comprises at least a portion of a hypodermis layer or at least a portion of a glandular layer. 
     Also disclosed herein is a method of creating a lesion in the skin wherein the skin has at least an external surface, a first layer below the external surface and a second layer, the method comprising the steps of: positioning a device adapted to radiate electromagnetic energy adjacent the external surface; radiating electromagnetic energy from the device, the microwave energy having an electric field component which is substantially parallel to a region of the external surface; and generating a standing wave pattern in the first layer, the standing wave pattern having a constructive interference peak in the first layer, wherein a distance from the constructive interference peak to the skin surface is greater than a distance from the constructive interference peak to an interface between the first layer and the second layer. In one embodiment, the electromagnetic energy comprises microwave energy. In one embodiment, the constructive interference peak is adjacent the interface. In one embodiment, the first layer has a first dielectric constant and the second layer has a second dielectric constant, wherein the first dielectric constant is greater than the second dielectric constant. In one embodiment, the first layer has a dielectric constant greater than about 25 and the second layer has a dielectric constant less than or equal to about 10. In one embodiment, the first layer comprises at least a portion of a dermis layer. In some embodiments, the second layer comprises at least a portion of a hypodermis layer or at least a portion of a glandular layer. 
     In another embodiment, disclosed is a method of creating a temperature gradient in the skin wherein the skin has at least an external surface, a first layer below the external surface and a second layer, the method comprising the steps of: positioning a device adapted to radiate electromagnetic energy adjacent the external surface; radiating electromagnetic energy from the device, the microwave energy having an electric field component which is substantially parallel to a region of the external surface; and generating a standing wave pattern in the first layer, the standing wave pattern having a constructive interference peak in the first layer, wherein a distance from the constructive interference peak to the skin surface is greater than a distance from the constructive interference peak to an interface between the first layer and the second layer. 
     In another embodiment, disclosed is a method of creating a lesion in a dermal layer of the skin, the dermal layer having an upper portion adjacent an external surface of the skin and a lower portion adjacent a subdermal layer of the skin, the method comprising the steps of: exposing the external surface to microwave energy having a predetermined power, frequency, and electric field orientation; generating a peak energy density region in the lower portion of the dermal layer; and continuing to radiate the skin with the microwave energy for a time sufficient to create a lesion, wherein the lesion begins in the peak energy density region. 
     In another embodiment, disclosed is a method of creating a lesion in a dermal layer of the skin wherein the skin has at least a dermal layer and a subdermal layer, the method comprising the steps of: positioning a device adapted to radiate microwave energy adjacent an external surface of the skin; and radiating microwave energy having an electric field component which is substantially parallel to a region of the external surface of the skin above the dermal layer, wherein the microwave energy has a frequency which generates a standing wave pattern in the dermal layer, the standing wave pattern having a constructive interference peak in the dermal layer in close proximity to an interface between the dermal layer and the subdermal layer. 
     In another embodiment, disclosed herein is a method of creating a lesion in a dermal layer of the skin wherein the skin has at least a dermal layer and a subdermal layer, the method comprising the steps of: positioning a device adapted to radiate microwave energy adjacent an external surface of the skin; radiating microwave energy having an electric field component which is substantially parallel to a region of the external surface of the skin above the dermal layer, wherein the microwave energy has a frequency which generates a standing wave pattern in the dermal layer, the standing wave pattern having a constructive interference peak in the dermal layer in close proximity to an interface between the dermal layer and the subdermal layer; and heating the lower portion of the dermal region using the radiated microwave energy to create the lesion. In one embodiment, a center of the lesion is positioned at the constructive interference peak. 
     In another embodiment, disclosed is a method of heating a tissue structure located in or near a target tissue layer, wherein the target tissue layer is below a first tissue layer, the first tissue layer being adjacent a skin surface, the method comprising the steps of: irradiating the target tissue layer and the first tissue layer through the skin surface with electromagnetic energy having predetermined frequency and electric field characteristics; and generating a power loss density profile wherein the power loss density profile has a peak power loss density in a region of the target tissue layer. In one embodiment, the tissue structure comprises a sweat gland. In one embodiment, heating the tissue structure is sufficient to destroy a pathogen located in or near the tissue structure. The pathogen may be bacteria. In some embodiments, the tissue structure is a sebaceous gland or at least a portion of a hair follicle. In some embodiments, the tissue structure may be selected from the group consisting of: telangiectasias, cellulite, varicose veins, and nerve endings. In one embodiment, heating the tissue structure is sufficient to damage the tissue structure. In one embodiment, the heat generates a lesion having an origin in the target tissue layer. The lesion grows to include the tissue structure. In one embodiment, the method further comprises the step of removing sufficient heat from the first layer to prevent the lesion from growing into the first layer. Removing sufficient heat from the first layer may comprise cooling the skin surface. In some embodiments, the target tissue layer may comprise a deep layer of the dermis or a glandular layer. In some embodiments, the electromagnetic energy has an electric field component which is substantially parallel to at least a portion of the skin surface or is parallel to at least a portion of the skin surface. In some embodiments, the electromagnetic energy radiates in a TE 10  mode or TEM mode. In some embodiments, the electromagnetic energy has a frequency in the range of between about 4 GHz and 10 GHz, 5 GHz and 6.5 GHz, or approximately 5.8 GHz. In one embodiment, the electromagnetic energy generates heat in the target tissue by dielectric heating. In one embodiment, the power loss density is generated by a standing wave pattern in the target tissue layer and the first tissue layer. The standing wave pattern may have a constructive interference peak in the region of the target tissue layer. The standing wave pattern may have a constructive interference minimum in the first tissue layer. In one embodiment, the origin of the lesion is in the region of the target tissue layer having the peak power loss density. In one embodiment, the lesion continues to grow through thermal conductive heating after electromagnetic energy is no longer applied. In one embodiment, the target tissue structure is heated primarily as a result of the thermal conductive heating. 
     In another embodiment, disclosed herein is a method of raising the temperature of at least a portion of a tissue structure located below an interface between a dermal layer and subdermal layer in skin, the dermal layer having an upper portion adjacent an external surface of the skin and a lower portion adjacent a subdermal region of the skin, the method comprising the steps of: radiating the skin with microwave energy having a predetermined power, frequency and e-field orientation; generating a peak energy density region in the lower portion of the dermal layer; initiating a lesion in the peak energy density region by dielectric heating of tissue in the peak energy density region; enlarging the lesion, wherein the lesion is enlarged, at least in part, by conduction of heat from the peak energy density region to surrounding tissue; removing heat from the skin surface and at least a portion of the upper portion of the dermal layer; and continuing to radiate the skin with the microwave energy for a time sufficient to extend the lesion past the interface and into the subdermal layer. In one embodiment, the tissue structure comprises a sweat gland. 
     Also disclosed herein in another embodiment is a method of raising the temperature of at least a portion of a tissue structure located below an interface between a dermal layer and a subdermal layer of skin, wherein the dermal layer has an upper portion adjacent an external surface of the skin and a lower portion adjacent a subdermal region of the skin, the method comprising the steps of: positioning a device adapted to radiate microwave energy adjacent the external surface of the skin; radiating microwave energy having an electric field component which is substantially parallel to a region of the external surface above the dermal layer, wherein the microwave energy has a frequency which generates a standing wave pattern in the dermal layer, the standing wave pattern having a constructive interference peak in the lower portion of the dermal layer; creating a lesion in the lower portion of the dermal region by heating tissue in the lower portion of the dermal region using the radiated microwave energy; removing heat from the skin surface and at least a portion of the upper portion of the dermal layer to prevent the lesion from spreading into the upper portion of the dermal layer; and ceasing the radiating after a first predetermined time, the predetermined time being sufficient to raise the temperature of the tissue structure. In some embodiments, the first predetermined time comprises a time sufficient to deposit enough energy in said lower portion of the dermal layer to enable said lesion to spread into the subdermal region or a time sufficient to enable heat generated by said radiation to spread to the tissue structure. In one embodiment, the step of removing heat further comprises continuing to remove heat for a predetermined time after the step of ceasing said radiating. In one embodiment, the constructive interference peak is located on a dermal side of the interface between the dermal layer and the subdermal layer. In one embodiment, the lesion starts at the constructive interference peak. 
     In another embodiment, disclosed herein is a method of controlling the application of microwave energy to tissue, the method comprising the steps of: generating a microwave signal having predetermined characteristics; applying the microwave energy to tissue, through a microwave antenna and a tissue interface operably connected to the microwave antenna; supplying a vacuum pressure to the tissue interface; and supplying cooling fluid to the tissue interface. In some embodiments, the microwave signal has a frequency in the range of between about 4 GHz and 10 GHz, between about 5 GHz and 6.5 GHz, or approximately 5.8 GHz. In one embodiment, the microwave antenna comprises an antenna configured to radiate electromagnetic radiation polarized such that an E-field component of the electromagnetic radiation is substantially parallel to an outer surface of the tissue. The microwave antenna may comprise a waveguide antenna. In some embodiments, the microwave antenna comprises an antenna configured to radiate in TE 10  mode or in TEM mode. In one embodiment, the tissue interface is configured to engage and hold skin. The skin may be in the axillary region. In one embodiment, the microwave antenna comprises an antenna configured to radiate electromagnetic radiation polarized such that an E-field component of the electromagnetic radiation is parallel to an outer surface of the tissue. In one embodiment, the tissue interface comprises a cooling plate and a cooling chamber positioned between the cooling plate and the microwave antenna. In one embodiment, the cooling plate has a dielectric constant between about 2 and 15. In one embodiment, the vacuum source is configured to supply vacuum pressure to the tissue interface. In some embodiments, the vacuum pressure is between about 400 mmHg to about 750 mmHg, or about 650 mmHg. In one embodiment, the cooling source is configured to supply a coolant to the tissue interface. In one embodiment, the coolant is a cooling fluid. In some embodiments, the cooling fluid has a dielectric constant of between about 70 and 90, or about 80, or between about 2 and 10, or about 2. In some embodiments, the cooling fluid has a temperature of between about −5° C. and 40° C. or between about 10° C. and 25° C. In one embodiment, the cooling fluid has a temperature of about 22° C. In some embodiments, the cooling fluid has a flow rate through at least a portion of the tissue interface of between about 100 mL and 600 mL per second or between about 250 mL and 450 mL per second. In one embodiment, the cooling fluid is configured to flow through the tissue interface at a velocity of between about 0.18 and 0.32 meters per second. In one embodiment, the cooling fluid is selected from the group consisting of glycerin, vegetable oil, isopropyl alcohol, and water, while in another embodiment, the cooling fluid is selected from the group consisting of water and water mixed with an alcohol. 
     Also disclosed, in another embodiment, is a method of positioning tissue prior to treating the tissue using radiated electromagnetic energy, the method comprising positioning a tissue interface adjacent a skin surface; engaging the skin surface in a tissue chamber of the tissue interface; substantially separating a layer comprising at least one layer of the skin from a muscle layer below the skin; and holding the skin surface in the tissue chamber. In one embodiment, the tissue interface comprises a tissue chamber, the tissue chamber having at least one wall and a tissue-contacting surface. In one embodiment, at least a portion of the tissue surface comprises a cooling plate positioned in the tissue chamber. In one embodiment, the tissue chamber has an aspect ratio in the range of between about 1:1 and 3:1, while in another embodiment, the tissue chamber has an aspect ratio of about 2:1. In one embodiment, the tissue chamber has a tissue acquisition angle between the wall and the tissue surface, the tissue acquisition angle being in the range of between about 2 degrees and approximately 45 degrees, while in another embodiment, the tissue acquisition angle is in the range of between about 5 degrees and approximately 20 degrees. In one embodiment, the tissue chamber has a tissue acquisition angle between the wall and the tissue surface, the tissue acquisition angle is about 20 degrees. 
     The various embodiments described herein can also be combined to provide further embodiments. Related methods, apparatuses and systems utilizing microwave and other types of therapy, including other forms of electromagnetic radiation, and further details on treatments that may be made with such therapies, are described in the above-referenced provisional applications to which this application claims priority, the entireties of each of which are hereby incorporated by reference: U.S. Provisional Patent Application No. 60/912,889, entitled “Methods and Apparatus for Reducing Sweat Production,” filed Apr. 19, 2007, U.S. Provisional Patent Application No. 61/013,274, entitled “Methods, Delivery and Systems for Non-Invasive Delivery of Microwave Therapy,” filed Dec. 12, 2007, and U.S. Provisional Patent Application No. 61/045,937, entitled “Systems and Methods for Creating an Effect Using Microwave Energy in Specified Tissue,” filed Apr. 17, 2008. While the above-listed applications may have been incorporated by reference for particular subject matter as described earlier in this application, Applicants intend the entire disclosures of the above-identified applications to be incorporated by reference into the present application, in that any and all of the disclosures in these incorporated by reference applications may be combined and incorporated with the embodiments described in the present application. 
     While this invention has been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention. For all of the embodiments described above, the steps of the methods need not be performed sequentially.