Abstract:
A temperature probe for monitoring temperatures of a surface of a tissue or organ within the body of a subject includes a section with a substantially two-dimensional arrangement and a plurality of temperature sensors positioned across an area defined by the substantially two-dimensional arrangement. Such an apparatus may be used in conjunction with procedures in which thermal techniques are used to diagnose a disease state or treat diseased tissue. Specifically, a temperature probe may be used to monitor temperatures across an area of a surface of a tissue or organ located close to the treated tissue to prevent subjection of the monitored tissue or organ to potentially damaging temperatures.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/406,771, filed on Mar. 18, 2009, titled LARGE SURFACE AREA TEMPERATURE SENSING DRIVE, now U.S. Pat. No. 9,155,476, issued Oct. 13, 2015, which claims the benefit of U.S. Provisional Patent Application No. 61/037,624, filed on Mar. 18, 2008, titled LARGE SURFACE AREA TEMPERATURE SENSING DEVICE. The entire disclosure of each of the forgoing patent applications is hereby incorporated herein. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to apparatuses for monitoring temperatures of an internal surface of a hollow organ in the body of a subject and, more specifically, to temperature monitoring apparatuses that are configured to monitor temperatures at different locations spread over an area of an internal surface of a hollow organ. The present invention also relates to methods in which temperatures across areas of an internal surface of a hollow organ are monitored, including techniques in which an adjacent tissue or organ is heated or cooled. 
       BACKGROUND OF RELATED ART 
       [0003]    A variety of techniques have been developed in which tissues or organs in a patient&#39;s body are heated or cooled. Tissues may be heated by a variety of techniques, including high frequency ultrasound, radiofrequency treatments, laser treatments, use of infrared radiation, and by direct application of thermal energy. Cooling is often effected cryogenically. Techniques that heat and cool tissues may be collectively referred to as “thermal techniques.” 
         [0004]    Thermal techniques are useful for diagnosing a variety of disease states and for treating a variety of disease states. More specifically, thermal techniques may be used to diagnose and/or treat cancerous tissues, to destroy diseased tissues, to congeal blood, and to perform a variety of other diagnostic and surgical procedures. Examples of organs that may be subjected to thermal techniques include the heart, the lungs, gastrointestinal organs, the liver, the pancreas, urological organs, prostates, reproductive organs, and skin. 
         [0005]    The degree of heating or cooling that is required to optimize the efficiency of some thermal techniques may adversely affect tissues or organs that are adjacent to a treated tissue or organ. For example, a great deal of heat is generated when left atrial ablation techniques are used to treat atrial fibrillation in human subjects. In addition to heating and treating the diseased tissue in the heart H, the esophagus E, which is adjacent to the left atrium LA of the heart H, as shown in  FIG. 1 , may also be heated. As  FIG. 1  illustrates, a typical human esophagus E typically has a narrow oval shape that resembles a pancake, with a large portion of the outer surface of the esophagus E located next to or in contact with the left atrium LA, although the size, shape, and/or position of the esophagus E may vary. In an average human adult, about 58 mm of the length and the majority of the front side of a 14 mm diameter esophagus E is located in proximity to or contacts the left atrium LA. As a consequence of this intimate arrangement between the esophagus E and the left atrium LA, the heat generated during left atrium ablation may damage the esophagus E and may, in some cases, create an esophageal fistula. Unfortunately, the complications that arise from esophageal fistula often do not present themselves until weeks after the procedure and, in many cases, at too late a time to treat and/or cure the sometimes fatal damage that has been done. 
         [0006]    In recognition of the potentially dire consequences of overheating the esophagus E during left atrial ablation, some physicians have started using catheters with single temperature sensors to monitor the temperature within the subject&#39;s esophagus E. Typically, a catheter with a size of 9 French (about 3 mm diameter) to about 18 French (about 64 mm diameter) is used in conjunction with a conventional temperature sensor (e.g., an esophageal stethoscope available from Smiths Medical of Hythe, Kent, United Kingdom). If the sensed temperature reaches a predetermined level, the physician may discontinue the left atrial ablation momentarily to allow the esophagus E to cool. The effectiveness of these techniques is limited, however, as a single temperature sensor may only monitor heat at a single location within the relatively large area of the esophageal wall located adjacent to the left atrium LA. 
         [0007]    In an apparent effort to reduce the likelihood of esophageal fistula during left atrial ablation procedures, a variety of different types of inflatable devices have been developed. Some inflatable devices are configured to cool the esophagus E during left atrial ablation. Other inflatable devices are configured to ensure contact between one or more temperature sensors and the interior surface of the front of the esophageal wall. Despite assertions to the contrary, since the esophagus E is confined between the left atrium LA of the relatively rigid heart H and the even more rigid vertebral column VC (see  FIG. 1 ), any change in the shape of the esophagus E by inflating a device that has been introduced into the esophagus E merely pushes or distends the esophagus E closer to, or into more intimate contact with, the left atrium LA. The obvious result of such movement or distension is an increase in the likelihood that a left atrial ablation procedure will cause an esophageal fistula. In addition, use of an inflatable device will undesirably prevent a subject from swallowing during the typically lengthy (two to four hour) procedure, which may unnecessarily require that the subject be placed under general anesthesia during the procedure. 
       SUMMARY 
       [0008]    The present invention includes various embodiments of temperature probes configured to be positioned against internal organ surfaces. A temperature probe that incorporates teachings of the present invention includes an elongate member and a plurality of temperature sensors carried at discrete locations along the length of the elongate member. When disposed within the interior of a hollow organ, a section of the elongate member is configured to have a substantially two-dimensional arrangement that arranges the temperature sensors in an area array. The arrangement of the shaped section of the elongate member is referred to as a “substantially two-dimensional arrangement” to account for the thicknesses of the elongate element and the temperature sensors carried thereby, as well as for any slight deviations of the elongate member from a desired plane for the two-dimensional arrangement. 
         [0009]    A substantially two-dimensional arrangement of a portion of a temperature probe of the present invention may, in some embodiments, be defined during manufacture of the temperature probe or apparatus (e.g., catheters, guide wires, shaping wires, etc.) that are to be used therewith. In other embodiments, a temperature probe or an apparatus that is configured for use therewith may be configured to enable a physician to define the substantially two-dimensional arrangement. 
         [0010]    In some embodiments, the elongate member comprises a flexible element with a section that, in a relaxed state, is pre-shaped to a desired, substantially two-dimensional arrangement. Elongate members with such characteristics may take on substantially linear, or one-dimensional, configurations when introduced into a linear catheter under stress but, upon removal of the pre-shaped section from the catheter, the pre-shaped section returns to its relaxed state, in which it has a substantially two-dimensional arrangement. 
         [0011]    In other embodiments, the elongate member is an element that has a substantially linear, or one dimensional, configuration, but includes a section that may be formed into a substantially two-dimensional arrangement of desired configuration. A section of an elongate member that is ordinarily substantially linear may take on a substantially two-dimensional arrangement when a wire that includes a section with the substantially two-dimensional arrangement is introduced into a lumen of the elongate member. Such a wire may itself be somewhat flexible or selectively flexible (e.g., depending upon its temperature, etc.), and its introduction into the interior of a hollow organ of a subject&#39;s body may be enabled by rigidity of a proximal and/or intermediate portion of the elongate member, a property (e.g., shape memory, etc.) of the material from which the wire is formed, or by any other suitable means. When the shaped portion of the wire is introduced into a corresponding flexible section of the elongate member, that section of the elongate member may assume the substantially two-dimensional arrangement. 
         [0012]    Other embodiments of temperature probes of the present invention include mechanisms for transforming substantially linear sections of elongate members to two-dimensional arrangements. In one such embodiment, an elongate element comprises a control wire, along with a multi-element portion along a portion of the length of the control wire. The multi-element portion includes at least two parallel arms that carry temperature sensors. While the multi-element portion is contained within a catheter, it may have a substantially linear configuration. Once the catheter has been introduced into the interior of a hollow organ, the control wire may be moved distally to push the multi-element portion out of a distal end of the catheter. The control wire may then be drawn back toward the distal end of the catheter, which engages an actuator associated with the at least two parallel arms and causes them to bow outwardly, forcing the multi-element portion into a substantially two-dimensional arrangement, such as a loop. 
         [0013]    Other techniques for causing a section of a temperature probe to assume a substantially two-dimensional configuration (e.g., aspiration of air from a lumen extending through a section of the temperature probe, introduction of pressure into a lumen extending through a section of the temperature probe, manipulation of a section of a temperature probe following its introduction into the body of a subject, etc.) are also within the scope of the present invention. 
         [0014]    The present invention includes techniques for introducing a temperature probe into the body of a subject with the temperature probe in a substantially linear, or one-dimensional, configuration, then allowing or causing a section of an elongate member of the temperature probe to assume the substantially two-dimensional arrangement when that section of the temperature probe is at a desired location within the subject&#39;s body. 
         [0015]    In addition to including various embodiments of temperature probes, the present invention also includes embodiments of methods, or procedures, in which the temperatures at various locations over an area of a body tissue are monitored. When such a procedure is conducted, a first tissue or organ of a subject&#39;s body is subjected to a thermal technique while temperature is monitored over an area of an adjacent, second tissue or organ of the subject&#39;s body. In some embodiments, the temperature of the second tissue or organ may be monitored without substantial deformation of the second tissue or organ, without substantial displacement of the second tissue or organ, and/or without preventing the second tissue or organ from functioning. Additionally, if any portion of the monitored area approaches a potentially damaging (cold or hot) temperature, precautionary measures may be taken. Various embodiments of such precautionary measures include, but are not limited to, temporary termination of the thermal technique, movement of the affected portion of the second tissue or organ away from the first tissue or organ, and/or changing the temperature of the affected portion of the second tissue or organ. 
         [0016]    In a specific embodiment, the method of the present invention may be effected during left atrial ablation, which is a surgical procedure that may be used to treat atrial fibrillation. During a left atrial ablation procedure, temperature may be monitored at a plurality of locations spaced over an area of an interior surface of a front portion of a subject&#39;s esophageal wall that is located adjacent to the left atrium of the subject&#39;s heart. Such temperature monitoring may be effected without any substantial change in the shape of the esophagus, without any substantial displacement of the monitored portion of the esophagus, and without blocking the esophagus or otherwise preventing the subject from swallowing. If any portion of the sensed area approaches a potentially damaging temperature, cautionary measures may be taken. In various embodiments, the left atrial ablation procedure may be temporarily terminated, the heated portion of the esophagus may be moved away from the left atrium, and/or the heated portion of the esophagus may be cooled. 
         [0017]    Other embodiments of procedures in which thermal techniques are employed are also within the scope of the present invention, including, without limitation, monitoring the temperature of the trachea during ablation of the pulmonary vein; monitoring the temperature of the ureters and/or colon during thermal treatment of the prostate; monitoring the temperature of and, optionally, flattening a portion of the duodenum of the small intestine during thermal treatment of the liver (e.g., to treat hepatic carcinoma, etc.); monitoring the temperature of the cystic duct, gall bladder, and/or stomach during thermal treatment of the liver; monitoring brain temperature through tissues lining the nasal cavities; monitoring the temperature of tissues in the nasal cavities during thermal pharyngeal procedures; and monitoring tissues of or adjacent to the kidneys while breaking up kidney stones. 
         [0018]    Other aspects, as well as various features and advantages, of the present invention will become apparent to those of ordinary skill in the art through consideration of the ensuing description, the accompanying drawings, and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    In the drawings, 
           [0020]      FIG. 1  is a cross-sectional representation of a portion of a human body illustrating the relationship between the esophagus and the heart; 
           [0021]      FIG. 2  depicts an embodiment of a temperature probe with an elongate member that includes a section with a substantially two-dimensional arrangement and temperature sensors arranged along the section of the elongate member in such a way that, when the section is in its substantially two-dimensional arrangement, the temperature sensors are arranged in an area array; 
           [0022]      FIGS. 2A and 2B  illustrate different embodiments of the elongate members of a temperature probe of the present invention; 
           [0023]      FIG. 3  illustrates the embodiment of temperature probe shown in  FIG. 2 , in a substantially linear, or one-dimensional, configuration when disposed within a lumen of a catheter having a substantially linear, or one-dimensional, configuration; 
           [0024]      FIG. 4  depicts relaxation of a segment of the embodiment of temperature probe shown in  FIG. 2  to its substantially two-dimensional arrangement upon exiting a distal end of the catheter of  FIG. 3 ; 
           [0025]      FIG. 5  shows an embodiment of a temperature probe with an elongate member that includes a flexible section that, in its relaxed state, may be substantially linear, or one-dimensional, and that includes a flexible section that carries a plurality of temperature sensors; 
           [0026]      FIG. 6  illustrates an embodiment of a shaped wire with a section that, in its relaxed state, has a substantially two-dimensional arrangement; 
           [0027]      FIG. 7  depicts introduction of the embodiment of temperature probe shown in  FIG. 5  into an interior of a hollow organ of a subject; 
           [0028]      FIG. 8  depicts introduction of the shaped wire of  FIG. 6  into the temperature probe of  FIG. 5 , with the section that has the substantially two-dimensional arrangement deformed to a substantially linear, or one-dimensional, configuration; 
           [0029]      FIG. 9  shows the flexible section of the temperature probe of  FIGS. 5 and 6  in substantially two-dimensional arrangement when the shaped portion of the wire of  FIG. 6  assumes its substantially two-dimensional arrangement within the flexible section; 
           [0030]      FIGS. 10 through 17  depict various embodiments of two-dimensional configurations in which a section of a temperature probe of the present invention may be arranged; 
           [0031]      FIGS. 18 through 20  illustrate an embodiment of temperature probe configured to be mechanically arranged in a substantially two-dimensional arrangement upon being positioned at or near a desired location; 
           [0032]      FIGS. 21 and 22  depict embodiments of temperature probes that include similar elements to the embodiment shown by  FIGS. 18 through 20 ; and 
           [0033]      FIG. 23  schematically depicts use of an embodiment of a temperature probe of the present invention in conjunction with a procedure in which a thermal technique is employed. 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    As shown in  FIG. 2 , a temperature probe  10  according to an embodiment of the present invention includes an elongate member  20  with a proximal portion  22 , an intermediate portion  24 , and a distal portion  26 . In addition, temperature probe  10  includes a plurality of temperature sensors  30  located along one or both of intermediate portion  24  and distal portion  26 . More specifically, temperature sensors  30  are positioned along a section  28  of elongate member  20  that is configured to have a substantially two-dimensional arrangement  40  when placed adjacent to or against an area of a surface of a tissue or organ in the body of a subject. Section  28  may also carry other elements, such as radioopaque markers, echogenic markers, other sensors, and the like. The shape of the substantially two-dimensional arrangement  40  distributes three or more temperature sensors  30  over an area (e.g., an area array in the depicted embodiment) that is relatively large when compared with the miniscule area covered by elongate member  20  itself. Temperature sensors  30  may be arranged across an area array in which at least two sensors  30  spaced laterally (x-axis X) apart from each other a first distance that exceeds a width of elongate member  20  and at least two sensors  30  spaced vertically (y-axis Y) apart from each other a second distance that is at least as great as the first distance. 
         [0035]    Elongate member  20  may, in various embodiments, have a length of about 20 cm to about 200 cm. The substantially two-dimensional arrangement  40  may have a width that exceeds a diameter of elongate member  20  by at least ten percent. In a specific embodiment, the substantially two-dimensional arrangement  40  covers an area with a width of about 10 mm to about 30 mm and a length of about 40 mm to about 80 mm, although substantially two-dimensional arrangements that cover narrower areas, wider areas, shorter areas, and longer areas are also within the scope of the present invention. 
         [0036]    In some embodiments, such as that depicted by  FIG. 2 , section  28  of elongate member  20  may be configured in the substantially two-dimensional arrangement  40  while in a relaxed state. The material from which elongate member  20  is formed may, in such embodiments, be somewhat flexible and elastic, at least under certain conditions (e.g., when placed under a load, with or without other conditions), to enable elongation of section  28  from the substantially two-dimensional arrangement  40  to a more linear, substantially one-dimensional, configuration. For example, section  28  may be elongated when placed under a load within the lumen  52  of a catheter  50 , as shown in  FIG. 3 . 
         [0037]    A variety of materials are suitable for forming a pre-shaped but flexible elongate member  20  (or at least section  28  thereof), including plastics and metal alloys. In embodiments where section  28  of elongate member  20  is formed from a plastic, the plastic may comprise a polyester, a polyurethane, a latex, polyvinyl chloride, and the polyether block amide marketed as PEBAX®. Metals and/or metal alloys that may be used to form elongate member  20  include, but are not limited to, shape memory alloys such as the nickel-titanium alloy referred to as NITINOL (for nickel titanium naval ordinance laboratory), steel, nickel-titanium, cobalt-chromium, and the cobalt-based alloy available under the trade name ELIGLOY®. An elongate member  20  that is formed from a metal or metal alloy may, in some embodiments, be coated with a softer polymer to prevent damage to the tissues and organs of the body of a subject into which temperature probe  10  is introduced. In some embodiments, the entire elongate member  20  may be formed from the same material, while other embodiments of elongate member  20  have hybrid constructions, such as a metal proximal portion  22  joined to a plastic or shape memory alloy distal portion  26 . 
         [0038]    As depicted by  FIG. 2A , in some embodiments, including embodiments in which elongate member  20  is formed from a plastic, elongate member  20  may comprise a tubular member with one or more lumens  21   a ,  21   b ,  21   c  (three are shown) extending therethrough. Lumen  21  a of such an elongate member  20  may be configured to accommodate wires (e.g., thermally conductive elements or electrically conductive wires  32  that lead to temperature sensors  30 , to other sensors, etc.) or other elements of temperature probe  10 . Lumen  21   b  may be configured to transport fluids into (e.g., fluids that provide a heat sink, cooled fluids to decrease a temperature of the sensed tissue, heated fluids to increase a temperature of the sensed tissue, etc.) or out of the subject&#39;s body, or to provide a pathway by which other medical devices may be introduced into the subject&#39;s body. Lumen  21   c  of elongate member  20  may be configured to receive a guide wire. 
         [0039]    As an alternative to wires  32  that extend through an interior (e.g., through a lumen  21   a ) of elongate member  20 , wires  32  may be carried upon an exterior of elongate member  20  (including embodiments in which elongate member  20  includes one or more lumens  21   a ,  21   b ,  21   c , as well as embodiments in which elongate member  20  lacks lumens, or has a solid cross-section), as illustrated by  FIG. 2B . Various embodiments of externally carried wires  32  include wires that are defined by etching a metal film formed on an external surface of elongate member  20 , wires that are stamped or printed onto the external surface of elongate member  20 , and wires that are discrete from, but carried by (e.g., wrapped around, etc.) the external surface of elongate member  20 . Of course, in embodiments where elongate member  20  is formed from a metal or metal alloy, electrically insulative elements (e.g., a dielectric coating, etc.) (not shown) may electrically isolate wires  32  that are carried by the exterior surface of elongate member  20  from the material of elongate member  20 . 
         [0040]    As depicted by  FIG. 2B , in some embodiments, elongate member  20  may have a solid cross section. 
         [0041]    Each temperature sensor  30  of temperature probe  10  may comprise any suitable type of temperature sensor known in the art. In various embodiments, thermocouples or thermistors that have been swaged to metal or thermally conductive (e.g., platinum, platinum-iridium, gold, etc.) sensors may be used as temperature sensors  30 . Each temperature sensor  30  may comprise a single element configured to detect a single temperature at a particular location. Alternatively, one or more temperature sensors  30  of a temperature probe  10  of the present invention may include a plurality of ganged temperature sensing elements, each of which may sense and/or report a different temperature to provide a more accurate temperature reading at a particular location. 
         [0042]    Wires  32  that communicate with temperature sensors  30  (or with individual temperature sensing elements of a sensor  30 ) extend proximally along elongate member  20  to a suitable connector  34  associated with proximal portion  22  of elongate member  20 . In some embodiments, connector  34  may comprise a known  400  series connector or a known series  700  connector, such as, or similar to, those manufactured by Datex Ohmeda, GE Medical, Nihon Kohden, or Vital Signs, Inc. 
         [0043]    Connector  34  enables connection of wires  32  and, thus, thermal sensors  30  to a suitable temperature monitor (not shown) that, in turn, communicates with a processing element (not shown) associated with a temperature display system  36 . In the depicted embodiment, display system  36  includes a display element  37  that shows the temperatures  38   a ,  38   b , etc., monitored at various locations that correspond to the locations of temperature sensors  30  in the substantially two-dimensional arrangement  40  of section  28  of elongate member  20 . Temperatures  38   a ,  38   b , etc., may be visually arranged in a manner that corresponds to the physical arrangement of temperature sensors  30  across the substantially two dimensional configuration  40 . Additionally, display system  36  may clearly identify the warmest and coolest sensed temperatures  38   a ,  38   b , etc. (e.g., by color, such as red and blue, respectively; by fast and slow flashing, respectively; etc.). Display system  36  may also present a rate  39  at which a sensed temperature is changing. The rate of temperature change may be displayed numerically or, as depicted, graphically. 
         [0044]    With reference to  FIG. 3 , an embodiment of a method for introducing a temperature probe  10  into a body of a subject is depicted. Specifically, temperature probe  10  is introduced into a lumen  52  of a substantially linear, or one-dimensional, catheter  50 . Catheter  50  is sufficiently rigid to cause section  28  of elongate element  20  of temperature probe  10  to flex and, thus, to straighten while catheter  50  maintains its substantial linearity. In some embodiments, catheter  50  may also be sufficiently flexible to move through curved cavities or vessels. With the non-linear, substantially two-dimensional arrangement  40  ( FIG. 2 ) of elongate element  20  of temperature probe  10  confined within lumen  52  of catheter  50  in a substantially linear configuration, temperature probe  10  may be easily introduced into a hollow area H within the body of a subject. 
         [0045]    Once distal portion  26  of elongate element  20  of temperature probe  10  has been positioned within hollow area H, distal portion  26  and section  28  may be pushed out of a distal end  54  of lumen  52  and into hollow area H, where section  28  may assume its relaxed, substantially two-dimensional arrangement  40 , as shown by  FIG. 4 . 
         [0046]    As an alternative to the use of a catheter to straighten temperature probe  10  and introduce a distal portion  26  of the same into hollow area H, a proximal end of a guide wire whose distal end has already been introduced into hollow area H may be introduced into a lumen  21   c  ( FIG. 2A ) of elongate member  30 . The rigidity of the guide wire may be sufficient to straighten section  28  of elongate member  30 , facilitating its introduction into hollow area H. Once section  28  has been introduced to a desired location, the guide wire may be removed from lumen  21   c , allowing section  28  to assume the substantially two-dimensional arrangement  40 . 
         [0047]    Another embodiment of temperature probe  10 ′ of the present invention is depicted by  FIGS. 5 through 9 . As depicted by  FIG. 5 , temperature probe  10 ′ comprises a substantially one-dimensional elongate member  20 ′ with the same features as elongate member  20  ( FIG. 2 ), with the primary exception being that section  28 ′ of elongate member  20 ′ is not shaped to have a substantially two-dimensional configuration  40  ( FIG. 2 ). Instead, section  28 ′ of elongate member  20 ′ of temperature probe  10 ′ is flexible, and may be deformed to take on a substantially two-dimensional configuration  40  ( FIG. 2 ). 
         [0048]    As depicted by  FIGS. 6 and 7 , a lumen  21 ′ that extends through the length of elongate member  20 ′ is configured to receive a shaped wire  60 . As shown in  FIG. 6 , prior to its introduction into lumen  21 ′, shaped wire  60  includes a section  62  that, in its relaxed state, has a substantially two-dimensional arrangement  64 . Shaped wire  60  is a flexible element that may be substantially straightened. In various embodiments, shaped wire  60  may be formed from a somewhat rigid, yet flexible plastic or a metal or metal alloy, such as a shape memory alloy that is flexible at room temperature, but that becomes rigid when heated (e.g., to a subject&#39;s body temperature, etc.). 
         [0049]      FIG. 7  illustrates the introduction of distal and intermediate portions  26 ′ and  24 ′ of elongate member  20 ′ of temperature probe  10  into a hollow area H of the body of a subject. As elongate member  20 ′ is introduced into hollow area H, so are temperature sensors  30  that are carried by section  28 ′. Due to its substantially linear, or one-dimensional configuration, known techniques may be used to introduce elongate member  20 ′ into hollow area H. 
         [0050]    Thereafter, shaped wire  60  may be introduced into lumen  21 ′ of elongate member  20 ′ of temperature probe  10 ′, as illustrated by  FIG. 8 . As shaped wire  60  is introduced into lumen  21 ′, section  62  of shaped wire  60  may be deformed (e.g., by the rigidity of a proximal portion  22 ′ and/or intermediate portion  24 ′ of elongate member  20 ′ ( FIG. 5 ), by temperature-dependent flexibility, etc.) to render section  62  substantially linear, or to have a one-dimensional configuration. Such deformation of section  62  enables shaped wire  60  to be easily introduced into a temperature probe  10 ′ that has been inserted into hollow area H. 
         [0051]    When section  62  ( FIG. 6 ) of shaped wire  60  has been introduced into section  28 ′ of elongate member  20 ′ of temperature probe  10 ′, section  62  may assume the substantially two-dimensional arrangement  64  (e.g., due to flexibility of section  28 ′, upon being heated to or beyond a transition temperature, etc.), as depicted by  FIG. 9 . As section  62  of shaped wire  60  assumes the substantially two-dimensional arrangement  64 , the flexibility of section  28 ′ also allows it to be drawn into a corresponding, substantially two-dimensional arrangement  40 ′. With section  28 ′ of elongate member  20 ′ in the substantially two-dimensional arrangement  40 ′, temperature sensors  30  ( FIG. 5 ) that are carried by section  28 ′ are spread across an area defined by the substantially two-dimensional arrangement  40 ′. 
         [0052]    Referring now to  FIGS. 10 through 16 , various embodiments of substantially two-dimensional arrangements  40  are depicted along with possible arrangements of temperature sensors  30 . Specifically,  FIGS. 10 through 12  show different embodiments of serpentine, or S, arrangements, while  FIGS. 13 and 14  depict examples of spiral, or pigtail, arrangements, and  FIGS. 15 and 16  illustrate different looped arrangements. Of course, substantially two-dimensional arrangements  40  of other shapes and configurations are also within the scope of the present invention. 
         [0053]      FIG. 17  illustrates a forked embodiment of temperature probe  10 ″ with an enlarged distal portion  22 ″ that includes two or more substantially parallel arms  22   a ″,  22   b ″, etc. (the depicted embodiment includes a distal portion  22 ″ with three arms  22   a ″,  22   b ″, and  22   c ″). As illustrated, each arm  22   a ″,  22   b ″, and  22   c ″ carries at least one temperature sensor  30 . In some embodiments, one or more arms  22   a ″,  22   b ″,  22   c ″, etc., may carry more than one temperature sensor  30 . 
         [0054]      FIGS. 18 through 20  illustrate another embodiment of temperature probe  100 , which is configured to be mechanically arranged in a substantially two-dimensional arrangement upon being positioned at or near a desired location. 
         [0055]    As shown in  FIG. 18 , temperature probe  100  includes an introductory catheter  150 , an elongate member  120  at least partially carried by introductory catheter  150 , and a plurality of temperature sensors  30  carried by a distal portion  126  of elongate member  120 . 
         [0056]    Elongate member  120  includes a proximally located pull wire  121 . A user engagement element  110  is associated with a proximal end  122  of pull wire  121  to facilitate movement of elongate member  120  through a lumen  152  of introductory catheter  150 . Pull wire  121  may extend along substantially the entire length of elongate member  120 . In the depicted embodiment, an intermediate portion  124  of pull wire  121  extends through a slip ring  125 , to which proximal ends  128  of two or more loop wires  127  are secured. Each loop wire  127  carries at least one temperature sensor  30  and, as depicted, at least one loop wire  127  may carry a plurality of temperature sensors  30 . Distal ends  129  of loop wires  127  are secured to pull wire  121  at or near its distal end  126 . In some embodiments, distal ends  129  of loop wires  127  may be fixedly secured to pull wire  121 . 
         [0057]    Distal end  126  of pull wire  121  may be configured or covered with an element that prevents trauma to the tissues of a subject as pull wire  121  is advanced distally and distal end  126  exits introductory catheter  150 . 
         [0058]    In the arrangement shown by  FIG. 18 , loop wires  127  are contained within lumen  152  of introductory catheter  150 . This arrangement facilitates the introduction of a distal portion of temperature probe  100  into a hollow area of a subject&#39;s body. Once the distal portion of temperature probe  100  has been placed at a desired location, elongate member  120  may be pushed distally through lumen  152  until proximal ends  128  of loop wires  127  and slip ring  125  have exited a distal end  154  of lumen  152  of introductory catheter  150 , as depicted by  FIG. 19 . 
         [0059]    Thereafter, as shown in  FIG. 20 , pull wire  121  may be proximally withdrawn. As pull wire  121  is proximally withdrawn, slip ring  125 , proximal ends  128  of loop wires  127 , and/or an engagement element (not shown) associated with slip ring  125  or with proximal ends  128  engage distal end  154  of introductory catheter  150 . As pull wire  121  is further withdrawn and proximal ends  128  are held into place relative to distal end  154 , loop wires  127  bow outwardly, providing a distal portion of temperature probe  100  with a substantially two-dimensional arrangement  140 . While the distal portion of temperature probe  100  is in the substantially two-dimensional arrangement  140 , temperature sensors  30  that are carried by loop wires  127  are spread across an area defined by the substantially two-dimensional arrangement  140 . The area over which loop wires  127  spread depends, of course, upon the degree to which pull wire  121  is withdrawn. 
         [0060]    With reference again to  FIG. 18 , user engagement element  110  and pull wire  121  may be associated with each other in such a way as to impart a user with control over an orientation of the substantially two-dimensional arrangement  140  ( FIG. 20 ). In some embodiments, user engagement element  110  and pull wire  121  may be manipulated to enable deflection (e.g., of up to about 5°, etc.) of the substantially two-dimensional arrangement  140  in any direction relative to an axis of elongate member  120 . 
         [0061]    A position of pull wire  121  relative to introductory catheter  150  and, thus, the substantially two-dimensional arrangement  140  ( FIG. 20 ) of the distal portion of temperature probe  100 , may be maintained by causing a locking element  159  associated with a proximal end  158  of introductory catheter  150  to engage a proximal portion  122  of pull wire  121  (e.g., by screwing locking element  159  down into proximal portion  122 , etc.). 
         [0062]    Instead of requiring that distal portion  126  of pull wire  121  be partially withdrawn into lumen  152  of introductory catheter  150  to expand loop wires  127 , in other embodiments, a flexible element, such as a balloon  170  enclosed within a mesh basket  180  or a mesh basket  180  alone, may be secured to loop wires  127 , as shown in  FIGS. 21 and 22 , respectively. Balloon  170  may be inflated by known techniques. Mesh basket  180  may comprise a compressed element that, when removed from lumen  152  of introductory catheter  150 , automatically expands. Mesh basket  180  may have a substantially two-dimensional configuration (e.g., having a narrow oval, or pancake, cross-sectional shape, etc.) so as to minimize or even prevent manipulation of the shape, displacement, and/or blockage of the hollow organ within which either of these elements are placed. In embodiments including a balloon  170 , mesh basket  180  may constrain the shape of the balloon  170  to the substantially two-dimensional configuration. In some embodiments, balloon  170  or mesh basket  180  may carry temperature sensors  30  until sufficient air pressure is added to balloon  170  to impart it with a more three-dimensional configuration. 
         [0063]    With reference now to  FIG. 23 , an embodiment of a method, or procedure, is depicted in which an embodiment of temperature probe  10  of the present invention is used to monitor temperatures at a plurality of locations across an area of a surface S of second tissue or an organ T 2  in the body of a subject as a first tissue or organ T 1  of the subject&#39;s body is subjected to a thermal technique. A plurality of temperature sensors  30  distributed across an area defined by a substantially two-dimensional arrangement  40  of a section  28  of an elongate member  20  is placed against surface S. Section  28  may be placed against surface S without substantially deforming surface S or the shape of second tissue or organ T 2  of which surface S is a part, without substantially displacing any part of second tissue or organ T 2 , and/or without preventing second tissue or organ T 2  from functioning properly as the temperature of surface S is monitored. In some embodiments, section  28  may deform slightly to conform to a shape of surface S. 
         [0064]    If any portion of the monitored area of surface S approaches a potentially damaging (cold or hot) temperature, precautionary measures may be taken. Various embodiments of such precautionary measures include, but are not limited to, temporary termination of the thermal technique, changing the temperature of the affected portion of second tissue or organ T 2 , and/or movement of the affected portion of second tissue or organ T 2  away from first tissue or organ T 1 . Various embodiments for moving the affected portion of second tissue or organ T 2  include, but are not limited to, deformation of second tissue or organ T 2  to a flattened (e.g., narrowed oval) shape (e.g., by modifying an area occupied by the substantially two-dimensional arrangement  40  of section  28 , etc), manipulation of a position of temperature sensor  10  within the body of the subject to move a portion of second tissue or organ T 2 , or any other suitable technique for moving tissue with temperature sensor  10 . 
         [0065]    Although the foregoing description contains many specifics, these should not be construed as limiting the scope of the present invention, but merely as providing illustrations of some embodiments. Similarly, other embodiments of the invention may be devised which lie within the scope of the present invention. Features from different embodiments may be employed in combination. The scope of the invention is, therefore, indicated and limited only by the appended claims and their legal equivalents, rather than by the foregoing description. All additions, deletions and modifications to the invention as disclosed herein which fall within the meaning and scope of the claims are to be embraced thereby.