Abstract:
Sinusitis, mucocysts, tumors, infections, hearing disorders, choanal atresia, fractures and other disorders of the paranasal sinuses, Eustachian tubes, Lachrymal ducts and other ear, nose, throat and mouth structures are diagnosed and/or treated using minimally invasive approaches and, in many cases, flexible catheters as opposed to instruments having rigid shafts. Various diagnostic procedures and devices are used to perform imaging studies, mucus flow studies, air/gas flow studies, anatomic dimension studies and endoscopic studies. Access and occluding devices may be used to facilitate insertion of working devices such as endoscopes, wires, probes, needles, catheters, balloon catheters, dilation catheters, dilators, balloons, tissue cutting or remodeling devices, suction or irrigation devices, imaging devices, sizing devices, biopsy devices, image-guided devices containing sensors or transmitters, electrosurgical devices, energy emitting devices, devices for injecting diagnostic or therapeutic agents, devices for implanting devices such as stents, substance eluting or delivering devices and implants, etc.

Description:
RELATED APPLICATION 
     This application is a continuation of U.S. Pat. No. 7,462,175 application Ser. No. 11/037,548 entitled “Devices, Systems and Methods for Treating Disorders of the Ear, Nose and Throat” filed on Jan. 18, 2005 which is a continuation-in-part of 1) U.S. Pat. No. 7,654,997 application Ser. No. 10/829,917 entitled “Devices, Systems and Methods for Diagnosing and Treating Sinusitis and Other Disorders of the Ears, Nose and/or Throat” filed on Apr. 21, 2004, 2) U.S. Pat. No. 7,361,168 application Ser. No. 10/912,578 entitled “Implantable Device and Methods for Delivering Drugs and Other Substances to Treat Sinusitis and Other Disorders” filed on Aug. 4, 2004 and 3) U.S. patent application Ser. No. 10/944,270, abandoned, entitled “Apparatus and Methods for Dilating and Modifying Ostia of Paranasal Sinuses and Other Intranasal or Paranasal Structures” filed on Sep. 17, 2004, the entire disclosure of each such parent application being expressly incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to medical devices, systems and methods and more particularly to minimally invasive devices, systems and methods for treating sinusitis and other ear, nose &amp; throat disorders. 
     BACKGROUND OF THE INVENTION 
     Surgical treatments for sinusitis and other disorders of the ear, nose and throat have evolved slowly over the years. In current clinical practice, functional endoscopic sinus surgery (FESS) is often used to treat sinusitis or other disorders where drainage of mucous is impaired and/or chronic infections are present. In FESS, an endoscope is inserted into the nose and, under visualization through the endoscope, the surgeon may remove diseased or hypertrophic tissue or bone and may enlarge the ostia of the sinuses to restore normal drainage of the sinuses. FESS procedures can be effective in the treatment of sinusitis and for the removal of tumors, polyps and other aberrant growths from the nose. Other endoscopic intranasal procedures have been used to remove pituitary tumors, to treat Graves disease (i.e., a complication of hyperthyroidism which results in protrusion of the eyes) and surgical repair of rare conditions wherein cerebrospinal fluid leaks into the nose (i.e., cerebrospinal fluid rhinorrhea). 
     In some instances, sinus and ENT surgery has been performed with the assistance of electronic navigation devices (i.e., “image-guided FESS”). In such image guided surgical procedures, integrated anatomical information is supplied through CT-scan images or other anatomical mapping data taken before the operation. Data from a preoperative CT scan or other anatomical mapping procedure is downloaded into a computer and special sensors known as localizers are attached to the surgical instruments. Thus, using the computer, the surgeon can ascertain, in three dimensions, the precise position of each localizer-equipped surgical instrument at any given point in time. This information, coupled with the visual observations made through the standard endoscope, can help the surgeon to carefully position the surgical instruments to avoid creating CSF leaks and to avoid causing damage to nerves or other critical structures. 
     Although FESS continues to be the gold standard therapy for severe sinuses, it has several shortfalls. Often patients complain of the post-operative pain and bleeding associated with the procedure, and a significant subset of patients remain symptomatic even after multiple surgeries. Since FESS is considered an option only for the most severe cases (those showing abnormalities under CT scan), a large population of patients exist that can neither tolerate the prescribed medications nor be considered candidates for surgery. Further, because the methodologies to assess sinus disease are primarily static measurements (CT, MRI), patients whose symptoms are episodic are often simply offered drug therapy when in fact underlying mechanical factors may play a significant role. To date, there is no mechanical therapy offered for these patients, and even though they may fail pharmaceutical therapies, no other course of action is indicated. This leaves a large population of patients in need of relief, unwilling or afraid to take steroids, but not sick enough to qualify for surgery. 
     Some experimental or investigational procedures have also been performed in an effort to treat sinusitis by methods that are less invasive and/or less damaging to ancillary tissues than FESS. For example, European physicians have reported the use of a hydrophilic guidewire and standard PTCA balloon catheter to treat restenosis of surgically created openings in diseased frontal sinuses and stenotic nasal conae. Göttmann, D., Strohm, M., Strecker, E. P., Karlsruhe, D. E., Balloon dilatation of Recurrent Ostial Oclusion of the Frontal Sinus, Abstract No. B-0453, European Congress of Radiology (2001); Strohm, M., Göttmann, D., Treatment of Stenoses of Upper Air Routes by Balloon Dilation, Proceeding of the 83 rd  Annual Convention of the Association of West German ENT Physicians (1999). The interventions described in this abstract were conducted only on frontal sinuses that had previously been surgically modified and nasal conae. These techniques were not reported to be useable for the treatment of sinus ostia that has not previously been surgically altered or ostia of sinuses other than the easily accessible frontal sinuses. Also, in these reported cases, standard vascular guidewires and angioplasty balloon catheters were used. The techniques described in these publications have not been widely adopted by ENT surgeons, possibly due to the fact that they lacked important novel improvements and modifications as described in this patent application and prior U.S. patent application Ser. Nos. 10/829,917, 10/912,578 and 10/944,270, of which this application is a continuation-in-part. 
     Other methods and devices for sinus intervention using dilating balloons have been disclosed in U.S. Pat. No. 2,525,183 (Robison) and United States Patent Publication No. 2004/0064150 A1 (Becker). For example, U.S. Pat. No. 2,525,183 (Robison) discloses an inflatable pressure device which can be inserted following sinus surgery and inflated within the sinus. The patent does not disclose device designs and methods for flexibly navigating through the complex nasal anatomy to access the natural ostia of the sinuses. The discussion of balloon materials is also fairly limited to thin flexible materials like rubber which are most likely to be inadequate for dilating the bony ostia of the sinus. 
     United States patent publication number 2004/0064150 A1 (Becker) discloses balloon catheters formed of a stiff hypotube to be pushed into a sinus. The balloon catheters have a stiff hypotube with a fixed pre-set angle that enables them to be pushed into the sinus. In at least some procedures wherein it is desired to position the balloon catheter in the ostium of a paranasal sinus, it is necessary to advance the balloon catheter through complicated or tortuous anatomy in order to properly position the balloon catheter within the desired sinus ostium. Also, there is a degree of individual variation in the intranasal and paranasal anatomy of human beings, thus making it difficult to design a stiff-shaft balloon catheter that is optimally shaped for use in all individuals. Indeed, rigid catheters formed of hypotubes that have pre-set angles cannot be easily adjusted by the physician to different shapes to account for individual variations in the anatomy. In view of this, the Becker patent application describes the necessity of having available a set of balloon catheters, each having a particular fixed angle so that the physician can select the appropriate catheter for the patient&#39;s anatomy. The requirement to test multiple disposable catheters for fit is likely to be very expensive and impractical. Moreover, if such catheter are disposable items (e.g., not sterilizable and reusable) the need to test and discard a number of catheters before finding one that has the ideal bend angle could be rather expensive. 
     The prior art has not provided catheters, devices, systems and methods that are optimal for minimally invasive treatment of sinusitis, mucocysts, tumors, infections, hearing disorders, fractures, choanal atresia or other conditions of the paranasal sinuses, Eustachian tubes, Lachrymal ducts and other ear, nose, throat or mouth structures. 
     SUMMARY OF THE INVENTION 
     In general, the present invention provides methods, devices and systems for diagnosing and/or treating sinusitis, mucocysts, tumors, infections, hearing disorders, fractures, choanal atresia or other conditions of the paranasal sinuses, Eustachian tubes, Ilachrymal ducts, ducts of salivary glands and other ear, nose, throat or mouth structures. 
     In accordance with the present invention, there are provided methods wherein one or more flexible catheters or other flexible elongate devices as described herein are inserted in to the nose, nasopharynx, paranasal sinus, Eustachian tubes, middle ear, lachrymal ducts, ducts of salivary glands or other anatomical passageways of the ear, nose, throat or mouth to perform an interventional or surgical procedure. Examples of procedures that may be performed using these flexible catheters or other flexible elongate devices include but are not limited to: delivering contrast medium; performing an imaging study, delivering a therapeutically effective amount of a therapeutic substance; implanting a stent or a tissue remodeling device, substance delivery implant or other therapeutic apparatus; cutting, ablating, debulking, cauterizing, heating, dilating or otherwise modifying tissue such as nasal polyps, aberrant or enlarged tissue, abnormal tissue, etc.; grafting or implanting cells or tissue; reducing, setting, affixing or otherwise treating a fracture; delivering a gene or gene therapy preparation; cutting, ablating, debulking, cauterizing, heating, freezing, lasing, forming an osteotomy or trephination in or otherwise modifying bony or cartilaginous tissue within paranasal sinus, nasopharynx, Eustachian tube, middle ear, Lachrymal duct or elsewhere within the ear, nose, throat or mouth; remodeling or changing the shape, size or configuration of a sinus ostium or other anatomical structure that affects drainage from one or more paranasal sinuses; removing puss or aberrant matter from the paranasal sinus or elsewhere within the nose; scraping or otherwise removing cells that line the interior of a paranasal sinus; removing all or a portion of a tumor; removing a polyp; delivering histamine, an allergen or another substance that causes secretion of mucous by tissues within a paranasal sinus to permit assessment of drainage from the sinus etc. 
     Still further in accordance with the invention, there are provided novel access, stabilizing and occluding devices. They may be used to facilitate insertion of working devices such as endoscopes, guidewires, catheters (e.g. balloon catheters), tissue cutting or remodeling devices, sizing devices, biopsy devices, image-guided devices containing sensors or transmitters, electrosurgical devices, energy emitting devices, devices for injecting diagnostic or therapeutic agents, devices for implanting devices such as stents, substance eluting devices, substance delivery implants, etc. into the paranasal sinuses and other structures in the ear, nose, throat or mouth for performing some or all of the procedures described herein. 
     Still further in accordance with the invention, there are presented several modalities for navigation and imaging of the interventional devices within the nose, nasopharynx, paranasal sinuses, Eustachian tubes, middle ear, lachrymal ducts, ducts of salivary glands or other anatomical passageways of the ear, nose, throat or mouth using endoscopic, fluoroscopic, radiofrequency localization, electromagnetic and other radiative energy based imaging and navigation modalities. These imaging and navigation technologies may also be referenced by computer directly or indirectly to pre-existing or simultaneously created 3-D or 2-D data sets which help the doctor place the devices within the appropriate region of the anatomy. 
     Still further in accordance with the invention, there are provided methods for improving drainage from a paranasal sinus that has a natural ostium that has not previously been surgically altered, said method comprising the steps of: A) providing an elongate guide (e.g., a wire, rod, probe, guidewire, flexible member, malleable member, tube, cannula, catheter, stylets, etc.) and a dilator (e.g., a dilation catheter, balloon catheter, expandable member, etc.); B) advancing the elongate guide to a position within or near the ostium; C) using the elongate guide to advance the dilator to a position where the dilator is within the ostium; and D) using the dilator to dilate the natural ostium. The dilation of the natural ostium may, in at least some cases, result in breaking or rearrangement of bone that underlies the mucosa of the ostium. 
     Still further in accordance with the invention, there is provided a method for treating a mucocyst or other or other flowable-substance-containing structure located within a paranasal sinus, said method comprising the steps of A) providing a penetrator that is useable to form an opening in the mucocyst or other flowable-substance-containing structure; B) providing a compressor useable to compress the mucocyst or other flowable-substance-containing structure after an opening has been formed therein by the penetrator such that its contents will be forced out of the opening formed by the penetrator; C) advancing the penetrator into the paranasal sinus and using the penetrator to form an opening in the mucocyst or other flowable-substance-containing structure; and D) positioning the compressor in the paranasal sinus and using the compressor to compress the mucocyst or other flowable-substance-containing structure such that its contents will be forced out of the opening formed by the penetrator. 
     Still further in accordance with the invention, there is provided a method for dilating a Eustachian tube in a human or animal subject, said method comprising the steps of: A) providing a guide member (e.g., a guidewire) that is insertable through the nose and is advanceable into the Eustachian tube through the pharyngeal ostium of the Eustachian tube and a dilator that is advanceable over the guidewire and useable to dilate the Eustachian tube; B) inserting the guidewire into the Eustachian tube; C) advancing the dilator over the guide member and into the Eustachian tube; and D) using the dilator to dilate the Eustachian tube. In some embodiments of this method, the guide member (e.g., guidewire) may have an anchor (e.g., a balloon) for holding the guide member in a substantially fixed position within the Eustachian tube, thereby guarding against inadvertent advancement of the guide member or dilation catheter into the middle ear as may injure the bones of the middle ear. In some embodiments, marker(s) such as radiopaque markers may be provided on the guide member and/or may be inserted into the adjacent ear canal next to the tympanic membrane to allow the operator to clearly view the location at which the Eustachian tube enters the middle ear, thereby further guarding against inadvertent advancement of the device(s) into the middle ear. 
     Still further in accordance with the invention, there is provided a method for modifying a bony structure within the nose or paranasal sinus human or animal subject, said method comprising the steps of: A) providing a direct viewing apparatus (e.g., a scope, rigid scope, flexible scope, camera, video camera, intranasal camera similar to an intraoral camera but sized for insertion into the nares or nasal cavity); B) inserting the direct viewing apparatus into the nose; C) advancing a guide device to a first location within the nasal cavity or paranasal sinus under direct viewing using the direct viewing apparatus; D) providing an indirect viewing apparatus (e.g., an imaging device, fluoroscope, fluoroscope with C-arm, magnetic resonance imaging device, tomographic device, CT scanner, electromagnetic navigational and/or guidance system, PET scanner, combination CT/PET scanner and optical coherence tomography device, etc.); E) advancing a working device (e.g., an endoscope, wire, probe, needle, catheter, balloon catheter, dilation catheter, dilator, balloon, tissue cutting or remodeling device, suction or irrigation device, imaging device, sizing device, biopsy device, image-guided device containing sensor or transmitter, electrosurgical device, energy emitting device such as laser, rf, etc., device for injecting diagnostic or therapeutic agent, device for implanting other articles such as stents, substance eluting or delivering device, implant, etc.) over the guide device to a second location within the nasal cavity or paranasal sinus, under indirect viewing using the direct viewing apparatus; and F) using the working device to perform a therapeutic or diagnostic procedure. 
     Still further in accordance with the invention, there is provided a method for determining the position of a device within the body of a human or animal subject, said method comprising the steps of A) providing a device having an electromagnetic element (e.g., a sensor or electromagnetic coil) thereon; B) providing a plurality of fiducial markers which emit electromagnetic energy and an attachment substance or apparatus for removably attaching the fiducial markers to teeth, bones or other anatomical structures; C) using the attachment substance or apparatus to removably attach the fiducial markers to teeth, bones or other anatomical structures of the subject&#39;s body; D) performing an imaging procedure to obtain an image of a portion of the subject&#39;s body including the fiducial markers; and, thereafter, E) advancing the device into the subject&#39;s body and detecting the electromagnetic element on the device as well as the electromagnetic energy emitted by the fiducial markers; and F) using the image obtained in Step D and the information detected in Step E to determine the current position of the device within the subject&#39;s body. 
     Further aspects, details and embodiments of the present invention will be understood by those of skill in the art upon reading the following detailed description of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a schematic diagram of the general working environment of an example of a system for catheter-based minimally invasive sinus surgery being used to perform a sinus surgery on a human patient. 
         FIG. 1A  shows a magnified view of region  1 A of  FIG. 1  showing a system for catheter-based minimally invasive sinus surgery of a human patient. 
         FIG. 1B  shows a perspective view of a treatment tray for catheter-based minimally invasive sinus surgery of a human patient. 
         FIG. 2A  shows a portion of a stabilizing device comprising a stabilizing member. 
         FIGS. 2B-2D  show various alternate embodiments of stabilizing member of  FIG. 2A . 
         FIG. 2E-2G  show perspective views of various embodiments of inflatable occluding devices. 
       FIGS.  3 A- 3 D′ show embodiments of stabilizing members comprising an adhesive element. 
         FIGS. 4A and 4B  show perspective views of an occluding device in deflated and inflated states respectively. 
         FIG. 5  shows a perspective view of a guide catheter comprising a plastically deformable (malleable) region. 
         FIG. 6  shows a perspective view of a guide catheter comprising a lubricious layer. 
         FIG. 6A  shows a crossectional view of the guide catheter of  FIG. 6  through the plane  6 A- 6 A. 
         FIG. 7  shows perspective view of an embodiment of a guide catheter comprising a straight hypotube. 
         FIG. 7A  shows a crossection of the guide catheter of  FIG. 7  through plane  7 A- 7 A. 
         FIG. 8  shows perspective view of a second embodiment of a guide catheter comprising a straight hypotube. 
         FIG. 8A  shows a crossection of the guide catheter of  FIG. 8  through plane  8 A- 8 A. 
         FIG. 8B  shows a crossection of the guide catheter of  FIG. 8  through plane  8 B- 8 B. 
         FIG. 8C  shows a perspective view of an embodiment of a guide catheter comprising a curved or bent hypotube to facilitate access to the frontal sinuses. 
         FIG. 8D  shows a perspective view of a second embodiment of a guide catheter comprising a curved or bent hypotube to facilitate access to the sphenoid sinuses. 
         FIG. 8E  shows a perspective view of an embodiment of a guide catheter comprising two bent or angled or curved regions to facilitate access to the maxillary sinuses. 
         FIG. 8F  shows a perspective view of a second embodiment of a guide catheter comprising two bent or angled or curved regions and a hypotube to facilitate access to the maxillary sinuses. 
         FIG. 8G  shows a coronal section of the paranasal anatomy showing a method of accessing a maxillary sinus ostium using the guide catheter of  FIG. 8F . 
         FIG. 8H  shows a sagittal section of the paranasal anatomy showing the method of  FIG. 8G  to access a maxillary sinus ostium using the guide catheter of  FIG. 8F . 
         FIG. 8I  shows a perspective view of an example of a guide catheter comprising a common proximal portion and a plurality of detachable distal tips. 
         FIG. 9  shows a perspective view of a set of devices to dilate or modify ostia or other openings in the ear, nose, throat or mouth structures. 
         FIG. 10  shows a perspective view of a probing device. 
         FIGS. 10A-10C  show various steps of a method of using the probing device shown in  FIG. 10  to access an anatomical region. 
         FIG. 11A  shows a perspective view of a first embodiment of a dual balloon catheter that can be used to perform a diagnostic or therapeutic procedure. 
         FIG. 11B  shows a perspective view of a second embodiment of a dual balloon catheter that can be used to perform a diagnostic or therapeutic procedure. 
         FIGS. 11C-11E  show perspective views of third, fourth and fifth embodiments respectively of dual balloon catheters for dilating an anatomical region. 
         FIGS. 11F-11J  show the various steps of a method of dilating an anatomical region using the catheter of  FIG. 11D . 
         FIGS. 12A-12C  show the various steps of a method of deploying a stent in the ear, nose, throat or mouth using a working catheter comprising a locating mechanism. 
         FIGS. 12D-12H  show the various steps of a method of dilating an anatomical opening in the ear, nose, throat or mouth using a combination of a dilating device and an anchoring device. 
         FIG. 13  shows a perspective view of a dilating device comprising an electrode element to reduce restenosis. 
         FIG. 14  shows a perspective view of an embodiment of a balloon catheter comprising a sizing balloon and a dilating balloon. 
         FIG. 14A  shows a crossectional view through the plane  14 A- 14 A of  FIG. 14 . 
         FIGS. 14B-14D  show the various steps of dilating an anatomical opening using the balloon catheter in  FIG. 14 . 
         FIG. 15  shows a perspective view of a balloon catheter comprising a sleeve for delivering diagnostic or therapeutic agents. 
         FIG. 15A  shows a crossectional view through plane  15 A- 15 A of  FIG. 15 . 
         FIG. 16  shows a perspective view of a balloon catheter comprising one or more agent delivery reservoirs. 
         FIG. 16A  shows a crossectional view through plane  16 A- 16 A of  FIG. 16 . 
         FIG. 17  shows a perspective view of a balloon catheter comprising a balloon comprising one or more micropores. 
         FIG. 17A  shows a crossectional view through the plane  17 A- 17 A of  FIG. 17 . 
         FIG. 18  shows a balloon catheter comprising a balloon having an outer coating of diagnostic or therapeutic agents. 
         FIGS. 18A-18C  show the steps of a method of using the balloon catheter of  FIG. 18  to dilate an anatomical region. 
         FIG. 19A  shows a perspective view of a lavage catheter. 
         FIG. 19B  shows a crossectional view through the plane  19 B- 19 B of  FIG. 19A . 
         FIG. 19C  shows the method of operation of lavage catheter of  FIG. 19A  to lavage an anatomical region. 
         FIG. 20A  shows a perspective view of the distal end of a second embodiment of a lavage catheter. 
         FIG. 20B  shows a perspective view of the distal end of the lavage catheter of  FIG. 20A  introduced in an anatomical region. 
         FIG. 20C  shows an embodiment of the lavage catheter of  FIG. 20A  being used to lavage an anatomical region. 
         FIG. 20D  shows a sagittal section of a human head showing the general working environment of the lavage devices of  FIGS. 20A-20C . 
         FIG. 21  shows a perspective view of a cutting device comprising cutting jaws. 
         FIG. 21A  shows a perspective view of the distal region of the cutting device of  FIG. 21  wherein the cutting jaws are closed as seen from the distal end of the cutting device. 
         FIG. 21B  shows a perspective view of one embodiment of the cutting jaws of the cutting device of  FIG. 21 . 
         FIG. 21C  shows a crossectional view of the cutting device in  FIG. 21  through cutting plane  21 C- 21 C. 
         FIG. 22A  shows a perspective view of an alternate embodiment of a device comprising cutting or gripping jaws. 
         FIG. 22B  shows a perspective view of the device of  FIG. 22A  wherein the cutting or gripping jaws of the cutting device are in a closed configuration. 
         FIGS. 23A-23C  show the various steps of a method of puncturing an anatomical region using a flexible, rotating drill shaft. 
         FIG. 23D  shows a sectional view of an embodiment of a drilling device. 
         FIGS. 24A-24C  show a sagittal section of an Ethmoid sinus showing various methods of treating Ethmoid sinus diseases by a minimally invasive approach. 
       FIGS.  24 A′- 24 A″″ show a method of creating drainage channels for sinus secretions in Ethmoid sinus. 
         FIG. 25A  shows a perspective view of an embodiment of an ostium enlarger and/or microshaver. 
         FIG. 25B  shows one embodiment of the device of  FIG. 25A  being used to remove tissue or matter. 
         FIG. 25C  shown another embodiment of the device of  FIG. 25A  being used to shave tissue or matter. 
         FIG. 25D  is an exploded view of the device of  FIG. 25C . 
         FIGS. 26A-26C  show various steps of a method of treating a mucocyst by a puncturing needle and a balloon catheter. 
         FIGS. 27A-27B  show various steps of a method of treating a mucocyst by a balloon catheter comprising a deployable puncturing needle. 
         FIGS. 28A-28C  show various embodiments of catheters comprising agent delivery needles. 
         FIG. 29A  illustrates an embodiment of a displacement catheter to displace and remove secretions in an anatomical region. 
         FIG. 29B  shows a sectional view of an anatomical region showing a method of displacing secretions by the displacement catheter of  FIG. 29A . 
         FIG. 30  shows a perspective view of an embodiment of an ultrasonic drilling device. 
         FIGS. 30A-30B  show a sectional view of an anatomical region showing a method of expanding an anatomical opening using the drilling device of  FIG. 30 . 
         FIG. 31  shows a sectional view of an embodiment of a catheter for providing an internal cast for fractured bony cavities. 
         FIG. 31A  shows a crossection through the outer balloon in the catheter of  FIG. 31  through plane  31 A- 31 A. 
         FIGS. 318-31D  show various steps of a method of providing an internal cast for a fractured bony cavity using the catheter shown in  FIG. 31   
         FIG. 32  shows an embodiment of a surgical navigation system comprising electromagnetic sensors. 
         FIG. 32A  shows an enlarged view of region  32 A in  FIG. 32 . 
         FIG. 33  shows a section of the anatomical region around a Eustachian tube (ET) showing a diagnostic or therapeutic procedure being performed by devices inserted through the pharyngeal ostium of the Eustachian tube. 
         FIG. 33A  shows an enlarged view of region  33 A in  FIG. 33 . 
         FIG. 33B  shows a front view of a human head with a portion of the face removed to show an embodiment of a method of introducing a guidewire into a Eustachian tube. 
         FIGS. 34A-34D  illustrate various examples of working elements that could be located on the diagnostic or therapeutic device in  FIG. 33 . 
         FIG. 35  shows a perspective view of an embodiment of a guidewire comprising a sensor used for surgical navigation. 
         FIG. 35A  shows an enlarged view of an embodiment of a low profile proximal region of the guidewire in  FIG. 35 . 
         FIG. 35B  shows a perspective view of a method of advancing a diagnostic or therapeutic device over the guidewire in  FIG. 35 . 
         FIG. 35C  shows a perspective view of an embodiment of a guidewire comprising a sensor having a diagnostic or therapeutic device preloaded on the guidewire. 
         FIG. 35D  shows a perspective view of a second embodiment of a guidewire comprising a sensor having a diagnostic or therapeutic device preloaded on the guidewire. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description, the accompanying drawings and the above-set-forth Brief Description of the Drawings are intended to describe some, but not necessarily all, examples or embodiments of the invention. The contents of this detailed description, the accompanying drawings and the above-set-forth Brief Description of the Drawings do not limit the scope of the invention in any way. 
     A number of the drawings in this patent application show anatomical structures of the ear, nose and throat. In general, these anatomical structures are labeled with the following reference letters: 
     
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 Nasal Cavity 
                 NC 
               
               
                   
                 Nasopharynx 
                 NP 
               
               
                   
                 Frontal Sinus 
                 FS 
               
               
                   
                 Frontal Sinus Ostium 
                 FSO 
               
               
                   
                 Ethmoid Sinus 
                 ES 
               
               
                   
                 Ethmoid Air Cells 
                 EAC 
               
               
                   
                 Sphenoid Sinus 
                 SS 
               
               
                   
                 Sphenoid Sinus Ostium 
                 SSO 
               
               
                   
                 Maxillary Sinus 
                 MS 
               
               
                   
                 Maxillary sinus ostium 
                 MSO 
               
               
                   
                 Mucocyst 
                 MC 
               
               
                   
                 Eustachian tube 
                 ET 
               
               
                   
                 Cochlea 
                 C 
               
               
                   
                 Tympanic cavity 
                 TC 
               
               
                   
                 Middle turbinate 
                 MT 
               
               
                   
                 Inferior turbinate 
                 IT 
               
               
                   
                 Uncinate 
                 UN 
               
               
                   
                   
               
             
          
         
       
     
       FIG. 1  shows a schematic diagram of the general working environment of an example of a system for catheter-based minimally invasive sinus surgery being used to perform a sinus surgery on a human patient. The human patient is treated by a working device  10 . Working device  10  may be connected to one or more auxiliary devices located on a treatment tray  12 . A C-arm fluoroscope  14  provides fluoroscopic visualization of anatomical regions during the procedure. An instrument console  16  comprising one or more functional modules  18  may also be present. Examples of functional modules that can be used with the invention are:
         1. Suction pump for delivering a controlled amount of negative pressure or vacuum to a suction device,   2. Irrigation pump to deliver saline, antibiotic solution or other suitable irrigation medium,   3. Power module to supply power to drills or other electrical devices,   4. Storage modules for storing instruments, medications etc.,   5. Energy delivery module to provide radiofrequency, laser, ultrasound or other therapeutic energy to a surgical device,   6. Fluoroscope, MRI, CT, Video, Endoscope or Camera or other imaging modules to connect or interact with devices used during various diagnostic or therapeutic procedures,   7. Display module e.g. a LCD, CRT or Holographic screen to display data from various modules such as an endoscope, fluoroscope or other data or imaging module,   8. Remote control module to enable an operator to control one or more parameters of one or more functional modules  18 ,   9. Programmable Microprocessor that can store one or more operation settings for one or more functional modules  18  etc., and   10. Stabilization device for holding various apparatuses during the procedure which may include a stabilization arm, table, clip, intranasal or extranasal inflatable support or robotically controlled apparatus,   11. Rotary drive module for rotating rotatable device such as a drill or auger (e.g., a motor having a rotation drive shaft or drive cable attached thereto.       

     One or more functional modules  18  may be connected to the working device  10 . Instrument console module  16  can be controlled by console control means  20 , e.g. a foot pedal controller, a remote controller etc. Instrument console  16  may be fitted with wheels to enable an operator to change the position of the instrument console  16  in an operating area. In one embodiment, instrument console module  16  and C-arm fluoroscope  14  are integrated in a single unit. 
       FIG. 1A  shows a magnified view of region  1 A of  FIG. 1  showing a system for catheter-based minimally invasive sinus surgery of a human patient. In  FIG. 1A , a balloon catheter is used as an example of working device  10 . Working device  10  has attachments for a variety of auxiliary devices such as a balloon inflation syringe  22 , a guidewire  24  and a suction or irrigation tube  26 . Working device  10  and the auxiliary devices may be detachably attached to treatment tray  12 . Treatment tray  12  may comprise one or more treatment tray controllers  28  to control one or more treatment parameters. Treatment tray  12  may comprise one or more storage modules to store devices used during a surgery e.g. irrigation bottles, swabs etc. 
       FIG. 1B  shows a perspective view of a treatment tray for catheter-based minimally invasive sinus surgery of a human patient. Treatment tray  12  comprises one or more device holders  30  to detachably hold devices during the surgery. In one embodiment, device holders  30  are detachably attached to device holder slots  32  on treatment tray  12 . Thus the position of device holders  30  on treatment tray  12  can be changed by removing a device holder  30  from a device holder slot  32  and transferring to a new device holder slot  32 . 
       FIG. 2A  shows a portion of a stabilizing device  100  comprising a stabilizing member  102 . Stabilizing member  102  comprises a lumen through which working device  10  can be introduced. In this example, stabilizing member  102  is located in a nostril. Alternatively, stabilizing member  102  may be located in other suitable regions of the head e.g. the nasal passages. 
     Stabilizing member  102  may be oriented to stabilizing device  100  in a variety of orientations. Also, the stabilizing member can be used to stabilize more than one working device.  FIGS. 2B-2D  show various alternate embodiments of stabilizing member  102  of  FIG. 2A .  FIG. 2B  shows an embodiment of a radially symmetrical stabilizing member  104 , wherein the axis  106  of stabilizing member  104  is substantially parallel to the axis  110  of stabilizing device  100 .  FIG. 2C  shows an embodiment of a radially symmetrical stabilizing member  112 . The axis  114  of stabilizing member  112  is substantially non-parallel to the axis  116  of stabilizing device  100 .  FIG. 2D  shows an embodiment of a stabilizing member  118 , wherein stabilizing member  118  comprises two lumens enclosing a first stabilizing device  120  and a second stabilizing device  122 . Suitable materials that can be used for constructing the stabilizing members are:
         Foam materials such as polyurethane foam, polyvinyl chloride foam, Thermal-Reactive Foam™ etc.,   Inflatable members such as compliant or non-compliant balloons,   Moldable materials such as silicone rubber or wax,   Metals such as stainless steel or super-elastic or shape memory metals such as Nitinol   Thermoplastic elastomers such as block copolymers e.g. styrene-butadiene-styrene (SBS) rubber or ionomers etc.       

     The stabilizing members may be pre-molded to a predefined shape. 
       FIGS. 2E-2G  show perspective views of various embodiments of inflatable occluding devices.  FIG. 2E  shows a partial view of an occluding device  124  comprising an inflatable occluding member  126 . Inflatable occluding member  126  may be made of compliant materials e.g. silicone rubber, or non-compliant materials e.g. polyethylene terephthalate (PET). Inflatable occluding member  126  can be inflated through an inflation port  127  located on the occluding device  124 . Occluding device  124  can have one or more device insertion ports. The device insertion ports can be used to insert a variety of diagnostic or therapeutic devices such as endoscopes, guidewires, catheters etc. In this example, occluding device  124  has a first device insertion port  128  and a second device insertion port  130 . The device insertion ports may comprise one or more flush ports. In this example, occluding device  124  comprises a first flush port  132  located on first device insertion port  128  and a second flush port  134  located on second device insertion port  130 . Such an occluding device may be used for occluding one or two nostrils to provide a gas-tight or liquid-tight seal against the nostril or to stabilize devices that are passed through the device insertion ports on the occluding device. 
     The inflatable occluding member may be made of variety of shapes.  FIG. 2F  shows an occluding device  136  comprising an inflatable occluding member  138  of an elongated shape wherein the diameter of the inflatable occluding member  138  tapers along the length of occluding device  136 . Inflatable occluding member  138  may also be spherical, disk shaped, cylindrical, conical etc. 
     The inflatable occluding member may comprise a variety of surface features. For example,  FIG. 2G  shows an occluding device  140  comprising an inflatable occluding member  142 . Inflatable occluding member comprises a series or parallel circular ribs on its surface. Other surface features such as coatings (e.g. friction increasing coatings, abrasion resisting coatings, puncture resisting coatings, conductive coatings, radiopaque coatings, echogenic coatings, thrombogenicity reducing coatings and drug releasing coatings etc.), braids, grooves etc. may also be present on inflatable occluding member  142 . 
     FIGS.  3 A- 3 D′ show embodiments of stabilizing members comprising an adhesive element.  FIG. 3A  shows front view of an embodiment of a stabilizing member  200  comprising a pair of upper wings  202  and a pair of lower wings  204 . In this embodiment, upper wings  202  are larger than lower wings  204 . Stabilizing member  200  further comprises one or more orifices  206  through which one or more working devices can be introduced. Stabilizing member  200  is made of a light weight, flexible material that conforms to the contours of the patient&#39;s body. Examples of such materials are woven and non-woven fabrics, plastic films (e.g. polyvinylchloride films, polypropylene films etc.), cellulose, paper etc. Stabilizing member  200  may have a porous structure for increased transmission of water vapor produced in perspiration from the skin under stabilizing member  200 . One surface of stabilizing member  200  is coated with an adhesive to enable stabilizing member  200  to adhere to a surface on a patient&#39;s body. A non-allergenic adhesive is used to minimize skin irritation. Examples of such adhesives are non-allergenic pressure-sensitive adhesives such as silicone pressure sensitive adhesives, rubber pressure sensitive adhesives and acrylic or hydrogel pressure sensitive adhesives. Stabilization member  200  may also be lubricated with a silicone or other biocompatible lubricant at the orifice to allow easier introduction and removal of devices. 
     Stabilizing member  200  may be used to stabilize one or more working devices.  FIG. 3B  shows a front view of stabilizing member  200  of  FIG. 3A  with two working devices: a first working device  208  and a second working device  210 .  FIG. 3C  shows a front view of the stabilizing member  200  of  FIG. 3A  with a single working device  212 . 
       FIG. 3D  shows a side view of stabilizing member  200  of  FIG. 3A  attached to a patient&#39;s body. Upper wings  202  are attached on the nose of the patient. Lower wings  204  are attached above the upper lip of the patient. A working device  10  is introduced through the orifice  206  into the patient&#39;s nose. FIG.  3 D′ shows a front view of stabilizing member  200  of  FIG. 3A  attached to a patient&#39;s body. 
       FIGS. 4A and 4B  show perspective views of an occluding device in deflated and inflated states respectively. Occluding device  300  comprises a shaft  302  and an inflatable balloon  304  located on distal region of shaft  302 . Shaft  302  has a diameter D.sub.1 and inflatable balloon  304  has a diameter D.sub.2 in the deflated state, wherein D.sub.2 is greater then D.sub.1. Inflatable balloon  304  can be made of compliant materials e.g. polyurethane, silicone etc. or non-compliant materials e.g. polyethylene terephthalate etc. Inflatable balloon  304  can be inflated through balloon inflation port  306  located on proximal region of occluding device  300 . The inflated diameter D.sub.3 of the inflatable balloon is greater than D.sub.2 and is particularly suitable for occluding the Nasopharynx. Occluding device  300  further comprises a series of aspiration ports  308  located proximal to inflatable balloon  304 . Aspiration ports  308  are connected to an aspiration lumen  310  to aspirate contents proximal to inflatable balloon  304 . 
     Any diagnostic or therapeutic device disclosed herein may comprise one or more malleable regions. For example,  FIG. 5  shows a perspective view of a guide catheter comprising a plastically deformable (malleable) region. Guide catheter  400  comprises a shaft  402  comprising a malleable region  404  located on distal region of shaft  402 . Shaft  402  may comprise stiffening elements e.g. a braid, hypotube etc. Malleable region  404  may comprise malleable metallic tubes, rods (e.g. rods embedded in shaft  402  etc.), wires etc. Examples of metals that can be used for constructing malleable region  404  are malleable stainless steel, fully annealed stainless steel, copper, aluminum etc. Guide catheter  400  further comprises a threaded luer  406  located on proximal end of shaft  402 . In this example, malleable region  404  is located on distal end of guide catheter  400 . Malleable region  404  can also be located on proximal region or any other intermediate region on shaft  402 . Shaft  402  may also comprise more than one malleable regions. Such a design comprising one or more malleable regions can be used for any of the devices mentioned herein such as catheters with working elements, guide catheters, guide catheters with a pre-set shape, steerable guide catheters, steerable catheters, guidewires, guidewires with a pre-set shape, steerable guidewires, ports, introducers, sheaths or other diagnostic or therapeutic devices. 
       FIG. 6  shows a perspective view of a guide catheter comprising a lubricious layer. Guide catheter  500  comprises a shaft  502  comprising a threaded luer  504  located on the proximal end of the shaft  502 .  FIG. 6A  shows a crossectional view of the guide catheter of  FIG. 6  through the plane  6 A- 6 A. Shaft  502  comprises a braid  506  embedded in the shaft. Shaft  502  further comprises a lubricious layer  508  located on the inner surface of shaft  502 . Lubricious layer  508  may be made of suitable materials such as Teflon liners, Teflon coatings or Teflon sheaths. Such a design comprising one or more lubricious layers can be used for any of the devices mentioned herein such as catheters with working elements, guide catheters, guide catheters with a pre-set shape, steerable guide catheters, steerable catheters, guidewires, guidewires with a pre-set shape, steerable guidewires, ports, introducers, sheaths or other diagnostic or therapeutic devices. 
       FIG. 7  shows perspective view of an embodiment of a guide catheter comprising a straight hypotube. Guide catheter  600  comprises a tubular element  602  and a hypotube  604  attached to the external surface of tubular element  602 . Suitable materials for constructing hypotube  604  are Stainless Steel 304, Nitinol etc. In one embodiment, hypotube  604  is annealed to the external surface of tubular element  602 . Tubular element  602  can be made from a variety of materials including Pebax, HDPE etc. Tubular element  602  may comprise a braid or a jacket. In an embodiment, tubular element  602  comprises a lubricious coating  605  on its inner surface. The lubricious coating  605  can be made of suitable lubricious materials such as Teflon. In an embodiment, tubular element  602  comprises a bent or angled region near the distal end of tubular element  602 . The bent or angled region may enclose an angle from 0 degrees to 180 degrees. Further this bent or angled region may be further bent out of plane to present a compound three-dimension end shape. Hypotube  604  can be malleable or substantially stiff. A malleable hypotube can be used in situations where the guide catheter  600  has to be bent or distorted to optimize its shape to conform to a patient&#39;s anatomy. Examples of materials that can be used to make a malleable hypotube are malleable stainless steel, fully annealed stainless steel, copper, aluminum etc. A substantially stiff hypotube can be used in situations where extra support is needed for introduction or removal or devices through guide catheter  600 . Examples of materials that can be used to make a substantially stiff hypotube are Stainless Steel 304, Nitinol etc. Hypotube  604  may be bent to a two-dimensional or three-dimensional shape. Distal tip of tubular element  602  may comprise a radio-opaque marker  606  e.g. a standard radio-opaque marker band. The proximal region of tubular element  602  comprises a threaded luer. 
       FIG. 7A  shows a crossectional view of guide catheter  600  of  FIG. 7  through plane  7 A- 7 A. The crossection of guide catheter  600  shows an outer hypotube  604  enclosing a tubular member  602  which in turn comprises a lubricious coating  605  located on the inner surface of tubular member  602 . 
       FIG. 8  shows a perspective view of a second embodiment of a guide catheter comprising a straight hypotube. Guide catheter  700  comprises a hypotube  702 . Proximal end of hypotube  702  may comprise a threaded luer  704 . Hypotube  702  encloses a tubular liner  706  that protrudes from the distal end of hypotube  702 . Suitable materials for constructing tubular liner  706  are PTFE, Nylon, PEEK etc. Distal region of tubular liner  706  is covered with a tubular element  708 . Tubular element  708  may be constructed of suitable materials such as Pebax, HDPE, Nylon etc. and may comprise a braid. Proximal end of tubular element  708  may be bonded to distal end of hypotube  702  or may overlap distal region of hypotube  702 . In one embodiment, distal region of tubular element  708  comprises a bent or angled region. In another embodiment, stiffness of tubular element  708  varies along the length of tubular element  708 . Tubular element  708  may comprise a radio-opaque marker band  710  near distal end of tubular element  708 .  FIG. 8A  shows a crossectional view of guide catheter  700  of  FIG. 8  through plane  8 A- 8 A showing hypotube  702  and tubular liner  706 .  FIG. 8B  shows a crossectional view of guide catheter  700  of  FIG. 8  through plane  8 B- 8 B showing tubular element  708  and tubular liner  706 . 
     The hypotubes disclosed above may be malleable or non-malleable. They may also comprise one or more bent or angled regions. For example,  FIG. 8C  shows a perspective view of an embodiment of a guide catheter comprising a curved or bent hypotube to facilitate access to the frontal sinuses. Guide catheter  712  comprises a hypotube  714  comprising a threaded luer  716  at the proximal end of hypotube  714 . Hypotube  714  may comprise one or more bent or angled regions. In this embodiment, the bent or angled region encloses an angle ranging from 60 degrees to 180 degrees. Hypotube  714  may be malleable or non-malleable. In this example, hypotube  714  encloses a tubular element  718 . Tubular element  718  may be constructed of suitable materials such as Pebax, HDPE etc. The distal region of tubular element  718  comprises a bent or angled region. In this embodiment, the bent or angled region encloses an angle ranging from 60 degrees to 170 degrees to facilitate access to the frontal sinuses using guide catheter  712 . Distal region of tubular element  718  may comprise a radio-opaque marker  720 .  FIG. 8D  shows a perspective view of a second embodiment of a guide catheter comprising a curved or bent hypotube to facilitate access to the sphenoid sinuses. The catheter construction is similar to the catheter in  FIG. 8C  except the bent or angled region of hypotube  714  encloses an angle ranging from 90 degrees to 180 degrees and the bent or angled region of tubular element  718  encloses an angle ranging from 120 degrees to 180 degrees. 
       FIG. 8E  shows a perspective view of an embodiment of a guide catheter comprising two bent or angled or curved regions to facilitate access to the maxillary sinuses. Guide catheter  740  comprises a tubular element  742  comprising a threaded luer  744  at the proximal end of tubular element  742 . Tubular element  742  further comprises a proximal bent, curved or angled region  746  enclosing an angle ranging from 90 degrees to 180 degrees and a distal bent, curved or angled region  748  enclosing an angle ranging from 90 degrees to 180 degrees. Tubular element  742  can be constructed from a variety of biocompatible materials such as Pebax, HDPE, Nylon, PEEK etc. and may comprise a braid. The inner surface of tubular element  742  may comprise a lubricious layer e.g. a Teflon layer. A curved region  750  is attached to the distal end of tubular element  742 . Curved region  750  may enclose an angle ranging from 75 degrees to 180 degrees. The stiffness of curved region  750  is more than the stiffness of tubular element  742  so that there is no significant change to the shape of curved region  750  during the operation of guide catheter  740 . The distal end of curved region  750  comprises a soft, atraumatic tip  752 . The distal end of curved region  750  may also comprise a radiopaque marker. Guide catheter  740  may be further bent out of plane to present a compound three-dimension end shape.  FIG. 8F  shows a perspective view of a second embodiment of a guide catheter comprising two bent or angled or curved regions and a hypotube to facilitate access to the maxillary sinuses. The construction of guide catheter  754  is similar to guide catheter  740  in  FIG. 8E  except that guide catheter  754  further comprises a hypotube  756  on the outer surface of the proximal region of guide catheter  754 . 
       FIG. 8G  shows a coronal section of the paranasal anatomy showing a method of accessing a maxillary sinus ostium using guide catheter  754  of  FIG. 8F . Guide catheter  754  is introduced through a nostril and advanced in the paranasal anatomy such that atraumatic tip  752  is located inside or adjacent to a maxillary sinus ostium MSO. Proximal bent, curved or angled region  746  allows guide catheter  754  to be positioned around the inferior turbinate IT. Similarly, distal bent, curved or angled region  748  allows guide catheter  754  to be positioned around the middle turbinate MT. A guidewire or a suitable diagnostic or therapeutic device may then be introduced through the lumen of guide catheter  754  into the maxillary sinus MS.  FIG. 8H  shows a sagittal section of the paranasal anatomy showing the method of  FIG. 8G  to access a maxillary sinus ostium using guide catheter  754  of  FIG. 8F . 
       FIG. 8I  shows a perspective view of an example of a guide catheter comprising a common proximal portion and a plurality of detachable distal tips. Distal end of common proximal portion  760  attaches to proximal end of a first detachable tip  762  by an attachment mechanism. First detachable tip  762  comprises an angled, curved or bent region enclosing an angle of 80-110 degrees suitable for access to the frontal and ethmoid sinuses. Similarly, distal end of common proximal portion  760  attaches to proximal end of a second detachable tip  764  by an attachment mechanism. Second detachable tip comprises two angled, curved or bent regions enclosing angles of 80-110 degrees and 80-110 degrees respectively. Such a design is suitable for access to the maxillary sinuses. Examples of attachment mechanisms are screw mechanisms, snap fitting mechanisms, slide fit mechanisms etc. Distal end of first detachable tip  762  and second detachable tip  764  may comprise a radiopaque marker such as a radiopaque band. Such a design comprising detachable distal regions can be used in a variety of diagnostic or therapeutic devices discloses herein. It can be used for easy access to one or more anatomical regions in the ear, nose, throat or mouth by using multiple detachable distal tips, wherein each detachable tip is optimized for access to a particular anatomical region. 
       FIG. 9  shows a perspective view of a set of devices to dilate or modify ostia or other openings in the ear, nose, throat or mouth structures. Guide catheter  800  comprises a shaft  802  comprising a threaded luer  804  at proximal end of shaft  802 . Distal end of shaft  802  comprises a radio-opaque marker band MB to enable the physician to identify the tip of shaft  802  in a fluoroscopic image. The distal end of shaft  802  may be substantially straight or may comprise one or more bent or angled regions. One or more distance markings DM may also be located on the shaft  802 . An optional subselective catheter  806  may also be present in the set of devices. Subselective catheter  806  comprises a shaft  808  comprising a threaded luer  810  at the proximal end of shaft  808 . Inner diameter of shaft  808  is smaller than inner diameter of shaft  802 . Distal end of the shaft  808  comprises a radio-opaque marker band MB to enable the physician to identify the tip of shaft  808  in a fluoroscopic image. Distal end of shaft  808  may be substantially straight or may comprise one or more bent or angled regions. One or more distance markings DM may also be located on the shaft  808 . Working device  812  comprises a shaft  814  comprising a working element  816  located on distal region of shaft  814  and a threaded luer  818  located on proximal end of shaft  814 . In this example, the working element  816  is a dilating balloon. Other examples of working elements include dilating stents, suction or irrigation devices, needles, polypectomy tools, brushes, brushes, energy emitting devices such as ablation devices, laser devices, image-guided devices containing sensors or transmitters, endoscopes, tissue modifying devices such as cutters, biopsy devices, devices for injecting diagnostic or therapeutic agents, drug delivery devices such as substance eluting devices, substance delivery implants etc. The distal end of shaft  814  may be substantially straight or may comprise a bent or angled region. One or more distance markings DM may also be located on shaft  814 . The set of devices further comprises a guidewire  820 . Guidewire  820  may be substantially straight or may comprise a bent or angled region. One or more distance markings DM may also be located on guidewire  820 . In one embodiment of a method using the abovementioned set of devices, guide catheter  800  is introduced into a patient&#39;s body so that distal end of guide catheter  800  is in the vicinity of an anatomical opening (e.g. an ostium) of an anatomical region (e.g. a paranasal sinus). Thereafter, guidewire  820  is introduced through guide catheter  800  into the anatomical region e.g. the paranasal sinus. If necessary, guide catheter  800  may be removed and the smaller subselective catheter  806  may be introduced over guide wire  820  into the paranasal sinus. Thereafter, working device  812  is introduced over guidewire  820  into the paranasal sinus and a diagnostic or therapeutic procedure is performed by working device  812 . In another embodiment of a method using the abovementioned set of devices, subselective catheter  806  is introduced into a patient&#39;s body so that distal end of subselective catheter  806  is in the vicinity of an anatomical opening (e.g. an ostium) of an anatomical region (e.g. a paranasal sinus). Thereafter, guidewire  820  is introduced through subselective catheter  806  into the anatomical region e.g. the paranasal sinus. Thereafter, subselective catheter  806  is removed. Larger guide catheter  800  is then introduced over guide wire  820 . Working device  812  is then introduced over guidewire  820  into the paranasal sinus and a diagnostic or therapeutic procedure is performed by working device  812 . This method embodiment enables a user to introduce larger working device  812  in the anatomical region. 
       FIG. 10  shows a perspective view of a probing device. The probing device  900  comprises a probing element  902  and a detachable handle  904 . Probing element  902  comprises an atraumatic tip  906  located on the distal end of probing element  902 . In one embodiment, atraumatic tip  906  is spherical. Probing element  902  can be made from a variety of biocompatible materials such as metals (e.g. stainless steel, titanium, Nitinol etc.) or polymers (e.g. Pebax, polyethylene etc.). Probing element  902  may be rigid or flexible or malleable. In the embodiment shown in  FIG. 10 , the distal region of the probing element  902  is malleable. This enables a physician to adjust probing device  900  for a patient&#39;s unique anatomy. Probing element  902  may comprise one or more curved or angled regions. Length of probing element  902  can range from 10 centimeters to 30 centimeters. Detachable handle can be attached to the probing element  902  by a variety of attachment mechanisms including screw arrangement, clipping mechanism etc. The tip of the probing element may further be modified to include a marker, sensor or transmitter capable of being tracked using one or more imaging modalities, such as x-ray, electromagnetic, radio-frequency, ultrasound, radiation, optics, and/or similar modalities. 
       FIGS. 10A-10C  show various steps of a method of using the probing device shown in  FIG. 10  to access an anatomical region. In  FIG. 10A , probing device  900  is advanced in to a patient&#39;s frontal sinus ostium through the nasal cavity. Atraumatic tip  906  prevents the probing device  900  from perforating and damaging healthy tissues. Thereafter, in  FIG. 10B , detachable handle  904  is detached from probing element  902 . Thereafter, in  FIG. 10C , a working device  908  e.g. a catheter is advanced over the probing element  902  into the patient&#39;s frontal sinus ostium. Working device  908  can then be used to perform a diagnostic or therapeutic procedure or introduce other devices. In this example, probing device  900  was used to access the patient&#39;s frontal sinus ostium. Other anatomical locations in the patient&#39;s body e.g. ostia of other paranasal sinuses, ostia of lachrymal ducts, regions in the Eustachian tube, ducts of salivary glands, etc. may be accessed by similar methods. It is also possible that working device  908  may be preloaded over probing element  902  and maintained in a retracted position relative to the probing element until distal portion of the probing element  902  is introduced into a desired location. Further, multiple working devices may be inserted within working device  908  or over working device  908  once it is properly positioned. 
       FIG. 11A  shows a perspective view of a first embodiment of a dual balloon catheter that can be used to perform a diagnostic or therapeutic procedure. Catheter  1000  comprises a catheter shaft  1002  and a proximal balloon  1004  and a distal balloon  1006  located on catheter shaft  1002 . A variety of diagnostic or therapeutic modules may be located in the inter-balloon region  1008  located between proximal balloon  1004  and distal balloon  1006 . Examples of such diagnostic or therapeutic modules are dilating or occluding balloons, dilating stents, suction or irrigation devices, needles, polypectomy tools, energy emitting devices like ablation devices, laser devices, image-guided devices containing sensors or transmitters, imaging devices, endoscopes, tissue modifying devices like cutters, biopsy devices, devices for injecting diagnostic or therapeutic agents, lavage devices, drug delivery devices such as substance eluting devices, substance delivery implants etc. etc. A catheter hub  1010  is located on the proximal end of catheter shaft  1002 . Catheter hub  1010  comprises a balloon inflation port  1012  that can be used to inflate both proximal balloon  1004  and distal balloon  1006 . 
       FIG. 11B  shows a perspective view of a second embodiment of a dual balloon catheter that can be used to perform a diagnostic or therapeutic procedure. The catheter  1014  shown in this embodiment further comprises a second balloon inflation port  1016 . Balloon inflation port  1012  is used to inflate proximal balloon  1004  and second balloon inflation port  1016  is used to inflate distal balloon  1006 . In one embodiment of a method using catheter  1014 , distal balloon  1006  is inflated before proximal balloon  1004 . 
       FIGS. 11C-11E  show perspective views of third, fourth and fifth embodiments respectively of dual balloon catheters for dilating an anatomical region. In  FIG. 11C , catheter  1020  comprises a catheter shaft  1022  comprising a catheter hub  1024  at the proximal end of catheter shaft  1022 . The distal region of catheter shaft  1022  comprises a proximal balloon  1026  and a distal balloon  1028 . Proximal balloon  1026  and distal balloon  1028  can be made from compliant or non-compliant materials. Catheter shaft  1022  further comprises a dilating balloon  1030  located between proximal balloon  1026  and distal balloon  1028 . Dilating balloon  1030  is constructed from suitable non-compliant materials such as Polyethylene terephthalate etc. The balloons are inflated through three balloon inflation ports located on catheter hub  1024 . A first balloon inflation port  1032  is used to inflate proximal balloon  1026 , a second balloon inflation port  1034  is used to inflate distal balloon  1028  and a third balloon inflation port  1036  is used to inflate dilating balloon  1030 .  FIG. 11D  shows a perspective view of catheter  1020  in  FIG. 11C  further comprising a stent  1038  disposed on dilating balloon  1030 . Several types of stent designs can be used to construct stent  1038  such as metallic tube designs, polymeric tube designs, chain-linked designs, spiral designs, rolled sheet designs, single wire designs etc. These designs may have an open celled or closed celled structure. A variety of fabrication methods can be used for fabricating stent  1038  including but not limited to laser cutting a metal or polymer element, welding metal elements etc. A variety of materials can be used for fabricating stent  1038  including but not limited to metals, polymers, foam type materials, plastically deformable materials, super elastic materials etc. Some non-limiting examples of materials that can be used to construct stent  1038  are Nitinol, stainless steel, titanium, polyurethane, gelfilm, polyethylene and silicones e.g. silastic. A variety of features can be added to stent  1038  including but not limited to radiopaque coatings, drug elution mechanisms etc.  FIG. 11E  shows a perspective view of catheter  1020  in  FIG. 11C  wherein proximal balloon  1026  and distal balloon  1028  are conical. Dual balloon catheters may also be used to deploy self-expanding stents at a target anatomical region. 
       FIGS. 11F-11J  show the various steps of a method of dilating an anatomical region using the catheter of  FIG. 11D . In  FIG. 11F , catheter  1020  is introduced into an anatomical region to be dilated. In one embodiment, catheter  1020  is introduced over a guidewire  1040 . In  FIG. 11G , distal balloon  1028  is inflated through second balloon inflation port  1034 . Thereafter, catheter  1020  is pulled in the proximal direction till distal balloon  1028  gets lodged in the anatomical region to be dilated. Thereafter in  FIG. 11H , proximal balloon  1026  is inflated through first balloon inflation port  1032 . This enables catheter  1020  to be securely lodged in the anatomical region to be dilated. Thereafter in  FIG. 11I , dilating balloon  1030  is inflated through third balloon inflation port  1036 . Inflated dilation balloon  1030  exerts an outward force on the anatomical region and causes it to dilate. This step also deploys stent  1038 . Thereafter in  FIG. 11J , proximal balloon  1026 , distal balloon  1028  and dilating balloon  1030  are deflated and catheter  1020  is removed by pulling catheter  1020  in the proximal direction. 
       FIGS. 12A-12C  show the various steps of a method of deploying a stent in the ear, nose, throat or mouth using a working catheter comprising a locating mechanism. In this example, the locating mechanism is a locator balloon. A working device  1100  is provided that comprises a locator balloon  1104  and a stent  1106  located on a stent deploying balloon  1108  located on a catheter shaft  1110 . Locator balloon  1104  is located on the distal region of the catheter shaft  1110  and stent  1106  is located proximal to the locator balloon  1104 . In  FIG. 12A , the working device  1100  is inserted into an anatomical region through an anatomical opening  1111  such that the locator balloon  1104  is located distal to anatomical opening  1111 . Examples of the anatomical region are paranasal sinuses, Eustachian tubes, lachrymal ducts and other structures in the ear, nose, throat or mouth etc. Examples of anatomical opening  1111  are ostia of paranasal sinuses, ostia of lachrymal ducts etc. In  FIG. 12B , locator balloon  1104  is inflated. The inflated diameter of the locator balloon is greater than the diameter of the anatomical opening. Working device  1100  is then pulled in the proximal direction such that locator balloon  1104  presses against the anatomical opening  1111 . This enables stent  1106  to be positioned accurately in a desired location relative to anatomical opening  1111 . In  FIG. 12C , stent deploying balloon  1108  is inflated to deploy stent  1106 . Thereafter, stent deploying balloon  1108  and locator balloon  1104  are deflated and the working device  1100  is removed by pulling it out in the proximal direction. Similar working catheters comprising locating mechanisms can also be used to deploy self-expanding stents. 
     In this example, the locating mechanism was a locator balloon. Other examples of locating device are deployable elements such as wire meshes, radially projecting wires, deployable devices located on guidewires (e.g. balloons, wire meshes etc.), devices deployed on pull-elements (e.g. radially expandable elements etc.) etc. 
       FIGS. 12D-12H  show the various steps of a method of dilating an anatomical opening in the ear, nose, throat or mouth using a combination of a dilating device and an anchoring device. In this example, the dilating device is a dilating balloon catheter and the anchoring device is an anchoring balloon catheter. In  FIG. 12D , an anchoring balloon catheter  1120  comprising a catheter shaft  1122  and an anchoring balloon  1124  is inserted over a guidewire GW into an anatomical opening. In one embodiment, shaft  1122  of anchoring balloon catheter  1120  is coated with a lubricious coating such as Teflon. In this example the anatomical opening is the sphenoid sinus ostium SSO of a sphenoid sinus SS. In  FIG. 12E , anchoring balloon  1124  is inflated. The inflated diameter of anchoring balloon  1124  is greater than the diameter of the anatomical opening. Thereafter, anchoring balloon catheter  1120  is pulled in the proximal direction so that anchoring balloon  1124  is anchored in the anatomical opening. In  FIG. 12F , a dilating balloon catheter  1126  comprising a shaft  1128  and a dilating balloon  1130  is advanced in the proximal direction over shaft  1122  of anchoring balloon catheter  1120 . Dilating balloon catheter  1126  is advanced till the distal portion of dilating balloon catheter  1126  touches anchoring balloon  1124 . This design accurately positions dilating balloon  1130  in a target location in the anatomical opening. Thereafter, in  FIG. 12G , dilating balloon  1130  is inflated to dilate the anatomical opening. Thereafter, in  FIG. 12H , the dilating balloon  1130  and anchoring balloon  1124  are deflated and dilating balloon catheter  1126  and anchoring balloon catheter  1120  are withdrawn from the anatomical opening by pulling them in the proximal direction. Dilating balloon  1130  can be made of suitable non-compliant materials e.g. polyethylene terephthalate etc. Anchoring balloon  1124  can be made of suitable compliant materials e.g. polyurethane, silicone etc. or non-compliant materials e.g. polyethylene terephthalate etc. Examples of anchoring devices are catheters comprising balloons, deployable elements such as wire meshes, radially projecting wires; deployable devices located on guidewires (e.g. balloons, wire meshes etc.); devices deployed on pull-elements (e.g. radially expandable elements etc.) etc. 
     Such a combination of an anchoring device and a working device inserted along the anchoring device can be used for a variety of other methods and devices disclosed herein for treating anatomical openings such as ostia of paranasal sinuses, ostia of lachrymal ducts, ducts of salivary glands, Eustachian tubes and other ear, nose, throat or mouth structures etc. 
       FIG. 13  shows a perspective view of a dilating device comprising an electrode element to reduce restenosis. Dilating device  1200  comprises a shaft  1202  and a dilating element  1204  located on the distal region of shaft  1202 . Examples of dilating elements are non-compliant dilating balloons, mechanically expandable elements etc. Dilating device  1200  further comprises an electrode element  1206  located on dilating element  1204 . Electrode element  1206  in combination with one or more surface electrodes attached to a surface of a patient&#39;s body delivers electrical energy to an anatomical region to be dilated. The electrical energy causes a controlled destruction of the adjacent anatomical region thereby reducing the risk to restenosis of the dilated region. Electrode element  1206  may have a variety of configurations including meshes, wires wound in a spiral configuration, wires wound in a sinusoidal configuration etc. Electrode element  1206  can be constructed from a variety of biocompatible metallic materials such as platinum-iridium alloys (e.g. 90% platinum/10% iridium) etc. Dilating device  1200  may further comprise an insulating layer between electrode element  1206  and dilating element  1204 . In one embodiment, electrode element  1206  is located on a sheath that can be advanced over dilating device  1200  such that electrode element  1206  is located above dilating element  1204 . 
       FIG. 14  shows a perspective view of an embodiment of a balloon catheter comprising a sizing balloon and a dilating balloon. A portion of the sizing balloon has been removed to show the dilating balloon underneath the sizing balloon. Balloon catheter  1300  comprises a shaft  1302  and a dilating balloon  1304  located on distal region of shaft  1302 . Dilating balloon  1304  can be made of suitable non-compliant materials e.g. polyethylene terephthalate, Nylon etc. Dilating balloon  1304  is inflated through a first balloon inflation opening  1305 . Balloon catheter  1300  further comprises a sizing balloon  1306  located around dilating balloon  1304 . Sizing balloon  1306  is made from a compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. Sizing balloon  1306  is inflated through a second balloon inflation opening  1307 . Dilating balloon  1304  and sizing balloon  1306  enclose an inter-balloon volume  1308 .  FIG. 14A  shows a crossection of the balloon catheter in  FIG. 14  through plane  14 A- 14 A. Shaft  1302  comprises a guidewire lumen  1310 , a first inflation lumen  1312  that terminates distally in first balloon inflation opening  1305  of  FIG. 14 , and a second inflation lumen  1314  that terminates distally in second balloon inflation opening  1307  of  FIG. 14 . 
       FIGS. 14B-14D  show the various steps of dilating an anatomical opening using the balloon catheter in  FIG. 14 . In  FIG. 14B , balloon catheter  1300  is introduced over a guidewire GW into an anatomical opening  1316  to be dilated. Examples of the types of anatomical openings  1316  that may be dilated by this invention include ostia of paranasal sinuses, Eustachian tubes, ostia of lachrymal ducts, etc. Thereafter, in  FIG. 14C , sizing balloon  1306  is inflated using an imagable inflating medium. Examples of suitable imagable inflating media are saline with a radiopaque contrast agent, carbon dioxide gas etc. Distal region of balloon catheter  1300  is subsequently imaged using a suitable imaging modality such as fluoroscopy or X-rays. This enables an operator to accurately estimate the size of anatomical opening  1316 . Such a balloon catheter is also suited for estimating the diameter of the narrowest region in a tubular anatomical region e.g. a Eustachian tube prior to performing a diagnostic or therapeutic procedure such as balloon dilation. On the basis of information obtained during step  14 C, balloon catheter  1300  may be repositioned and step  14 C repeated if necessary. Thereafter, in step  14 D, sizing balloon  1306  is deflated. Also in step  14 D, dilating balloon  1304  is inflated to dilate a target region in anatomical opening  1316 . Thereafter, dilating balloon  1304  is deflated and balloon catheter  1300  is withdrawn from anatomical opening  1316 . In one embodiment, sizing balloon  1306  may be reinflated after a balloon dilation procedure to obtain feedback about the performance of the balloon dilation procedure. 
       FIG. 15  shows a perspective view of a balloon catheter  1400  for delivering diagnostic or therapeutic agents. This balloon catheter  1400  comprises a catheter shaft  1402  which may be flexible, malleable or rigid, and a dilating balloon  1404  located on the distal region of shaft  1402 . Dilating balloon  1404  can be made of any suitable compliant or non-compliant materials (e.g. polyethylene terephthalate etc.). An outer balloon or sheath  1406  covers the dilating balloon  1404 , as shown in the cut-away view of  FIG. 15 . Sheath  1406  can be made of suitable non-compliant materials e.g. polyethylene terephthalate etc. or compliant or semi-compliant materials such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. Sheath  1406  comprises one or more pores  1408  through which diagnostic or therapeutic agents can be delivered to the surrounding anatomy. Pores  1408  may have a pore size ranging from sub-micron to a few microns. Dilating balloon  1404  is inflated by a balloon inflation lumen  1410 . The diagnostic or therapeutic agents can be delivered to the region between sheath  1406  and dilating balloon  1404  by an agent delivery lumen  1412 . In this particular embodiment, sheath  1406  is attached to shaft  1402 .  FIG. 15A  shows a crossection through the plane  15 A- 15 A of  FIG. 15  showing shaft  1402  comprising balloon inflation lumen  1410 , agent delivery lumen  1412  and a guidewire lumen  1414 . 
       FIG. 16  shows a perspective view of a balloon catheter comprising one or more agent delivery reservoirs. Balloon catheter  1500  comprises a shaft  1502  and a balloon  1504  located on the distal region of shaft  1502 . Balloon  1504  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon, etc., or from non-compliant materials such as polyurethane, etc. Balloon catheter  1500  further comprises one or more agent delivery reservoirs  1506  located on balloon  1504 . Agent delivery reservoirs  1506  contain one or more diagnostic or therapeutic agents absorbed in a matrix. Examples of diagnostic or therapeutic agents are contrast agents, pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an anesthetic agent with or without vasoconstrictor (e.g., Xylocaine with or without epinephrine, Tetracaine with or without epinephrine), an analgesic agent, an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, anti-proliferative agents, hemostatic agents to stop bleeding, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations etc. When balloon  1504  is inflated to dilate an anatomical region, it exerts pressure on agent delivery reservoirs  1506 . This pressure squeezes out the one or more diagnostic or therapeutic agents absorbed in the matrix and causes them to be released into the anatomical region. In one embodiment, agent delivery reservoirs  1506  comprise diagnostic or therapeutic agents absorbed in a porous matrix formed of a porous material such as a flexible or rigid polymer foam, cotton wadding, gauze, etc. Examples of biodegradable polymers that may be foamed or otherwise rendered porous include polyglycolide, poly-L-lactide, poly-D-lactide, poly(amino acids), polydioxanone, polycaprolactone, polygluconate, polylactic acid-polyethylene oxide copolymers, modified cellulose, collagen, polyorthoesters, polyhydroxybutyrate, polyanhydride, polyphosphoester, poly(alpha-hydroxy acid) and combinations thereof. Examples of non-biodegradable polymers that may be foamed or otherwise rendered porous include polyurethane, polycarbonate, silicone elastomers etc.  FIG. 16A  shows a crossection view through plane  16 A- 16 A of  FIG. 16  showing shaft  1502  comprising a balloon inflation lumen  1508  and a guidewire lumen  1510 . 
       FIG. 17  shows a perspective view of a balloon catheter comprising a balloon comprising one or more micropores or openings. Balloon catheter  1600  comprises a shaft  1602  comprising a dilating balloon  1604  located on the distal region of shaft  1602 . Dilating balloon  1604  can be made of suitable non-compliant materials e.g. polyethylene terephthalate etc. Dilating balloon  1604  comprises one or more micropores  1606  of a pore size ranging from submicron (e.g. 0.5 micron) to a few microns. Micropores  1606  can be formed on material of dilating balloon  1604  by various processes including mechanical punching, mechanical drilling, irradiation e.g. directing a laser beam or an ion or electron beam at the balloon material etc. Dilating balloon  1604  is inflated using an inflating medium comprising one or more diagnostic or therapeutic agents to be delivered to a target anatomical region such as ostia of paranasal sinuses, ostia of lachrymal ducts, ducts of salivary glands, Eustachian tubes etc. Examples of diagnostic or therapeutic agents are contrast agents, pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), an anesthetic agent, an analgesic agent, a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, anti-proliferative agents, hemostatic agents to stop bleeding, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations etc. When dilating balloon  1604  is inflated, a portion of the inflating medium seeps out of dilating balloon  1604  through micropores  1606  and thus is delivered to the adjacent anatomical regions. Thus dilation and agent delivery can be achieved in a single step.  FIG. 17A  shows a crossectional view through the plane  17 A- 17 A of  FIG. 17  showing shaft  1602  comprising a guidewire lumen  1608  and a balloon inflation lumen  1610 . 
       FIG. 18  shows a balloon catheter comprising a balloon having an outer coating of diagnostic or therapeutic agents. Balloon catheter  1700  comprises a shaft  1702  and a dilating balloon  1704  located on the distal region of shaft  1702 . Dilating balloon  1704  can be made of suitable non-compliant materials e.g. polyethylene terephthalate etc. Dilating balloon  1704  comprises a coating  1706  of one or more diagnostic or therapeutic agents on the outer surface of dilating balloon  1704 . Coating  1706  may comprise diagnostic or therapeutic agents located in a suitable carrier medium. In one embodiment, the carrier medium is a hydrogel. In another embodiment, the carrier medium is a solid having the consistency of wax e.g. sterile bone wax. In another embodiment, the carrier containing the agents can be deposited on the outer surface of dilating balloon  1704  just before balloon catheter  1700  is used for performing a diagnostic or therapeutic procedure. Coating  1706  may be present on the surface of dilating balloon  1704  in a variety of configurations. In one embodiment, coating  1706  is in the form of parallel strips of a carrier medium comprising one or more diagnostic or therapeutic agents. The coating may also be in the form of an annular layer, a plurality of discrete spots etc. When dilating balloon  1704  is inflated to dilate an anatomical region, coating  1706  comes into contact with the adjacent anatomical region. A portion of coating  1706  is deposited on the adjacent anatomical region which delivers the diagnostic or therapeutic agents to the adjacent anatomical region. Thus dilation and agent delivery can be achieved in a single step. In one embodiment, coating  1706  comprises a hemostatic material with a consistency of bone-wax. 
       FIGS. 18A-18C  show the steps of a method of using the balloon catheter of  FIG. 18  to dilate an anatomical region. In  FIG. 18A , balloon catheter  1700  is introduced in an anatomical region  1708 . Balloon catheter  1700  is positioned such dilating balloon  1704  is located in the target region to be dilated. Thereafter, in  FIG. 18B , dilating balloon  1704  is inflated. This dilates anatomical region  1708  and deposits a portion of coating  1706  on the dilated region. Thereafter, in  FIG. 18C , dilating balloon  1704  is deflated and balloon catheter  1700  is withdrawn from anatomical region  1708  leaving behind a deposited layer  1710  of coating  1706  on the dilated anatomical region  1708 . 
       FIG. 19A  shows a perspective view of a lavage catheter. Lavage catheter  1800  comprises a shaft  1802  and an occluding balloon  1804  located on the distal region of shaft  1802 . Occluding balloon  1804  can be made of suitable compliant materials e.g. polyurethane, silicone etc. or non-compliant materials e.g. polyethylene terephthalate etc. Lavage catheter  1800  further comprises a flushing tip  1806  and an aspiration tip  1808  located on the distal end of shaft  1802 . In  FIG. 19A , lavage catheter  1800  is introduced over a guidewire GW into an anatomical region e.g. a sphenoid sinus SS through an anatomical opening e.g. a sphenoid sinus ostium SSO.  FIG. 19B  shows a crossectional view through the plane  19 B- 19 B of  FIG. 19A . Shaft  1802  comprises an aspiration lumen  1810 , a flushing lumen  1812  and a guidewire lumen  1814 . Distal end of aspiration lumen  1810  opens at the distal end of aspiration tip  1808  and distal end of flushing lumen  1812  opens at the distal end of flushing tip  1806 . 
       FIG. 19C  shows the method of operation of lavage catheter  1800  of  FIG. 19A  to lavage an anatomical region. In  FIG. 19C , occluding balloon  1804  is inflated and lavage catheter  1800  is pulled in the proximal direction till occluding balloon occludes the anatomical opening e.g. sphenoid sinus ostium SSO. Thereafter, a flushing medium introduced in the anatomical region through flushing tip  1806 . The flushing medium may be introduced in lavage catheter  1800  from a flushing medium container  1816  e.g. a saline bag connected to the proximal region of lavage catheter  1800 . The flushing medium is aspirated from the anatomical region through aspiration tip  1808 . The proximal end of lavage catheter  1800  may be connected to a collection vessel  1818  to collect the aspirated flushing medium. In one embodiment, collection vessel  1818  is further connected to wall suction. 
       FIG. 20A  shows a perspective view of the distal end of a second embodiment of a lavage catheter. Lavage catheter  1900  comprises a tubular member  1902  comprising a one or more openings  1904  located on the distal region of tubular member  1902 . Tubular member  1902  may be made from a variety of materials such as silicone elastomers, Pebax, HDPE etc. Distal region of tubular member  1902  may comprise a curved or bent region. Tubular member  1902  comprises a first lumen connected to openings  1904 . Suitable diagnostic or therapeutic fluids can be introduced or removed through openings  1904 . Examples of such fluids are saline, pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, a contrast agent, an anesthetic agent with or without vasoconstrictor (e.g., Xylocaine with or without epinephrine, Tetracaine with or without epinephrine), an analgesic agent, hemostatic agents to stop bleeding, anti-proliferative agents, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations etc. In one embodiment, tubular member  1902  comprises a second lumen that acts as a guidewire lumen. 
       FIG. 20B  shows a perspective view of the distal end of the lavage catheter of  FIG. 20A  introduced in an anatomical region. In this example, the anatomical region is a maxillary sinus MS comprising a maxillary sinus ostium MSO. Lavage catheter  1900  may be introduced into the anatomical region by an over-the-wire method, through a cannula, or by a variety of methods disclosed in this patent application and in the patents documents incorporated herein by reference. Other examples of anatomical regions that can be treated using lavage catheter  1900  are other paranasal sinuses, lachrymal ducts, Eustachian tubes, and other hollow organs in the ear, nose, throat or mouth. 
       FIG. 20C  shows an embodiment of the lavage catheter of  FIG. 20A  being used to lavage an anatomical region. In this embodiment, lavage catheter  1900  further comprises an outer sheath  1910  comprising an occluding balloon  1912  located on the distal region of outer sheath  1910 . Occluding balloon  1912  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. or from non-compliant materials such as polyurethane etc. Outer sheath  1910  covers tubular member  1902  such that outer sheath and tubular member  1902  enclose a suction lumen  1914  between them. Tubular member  1902  is used to introduce a lavage fluid  1916  into the anatomical region through openings  1904 . Suction lumen  1914  is used to remove lavage fluid  1916  from the anatomical region. 
       FIG. 20D  shows a sagittal section of a human head showing the general working environment of the lavage devices of  FIGS. 20A-20C . Distal end of lavage catheter  1900  is introduced into an anatomical region such as Ethmoid air cell EAC. Lavage catheter  1900  may be introduced into the EAC by an over-the-wire method, through a cannula, or by a variety of methods disclosed in this patent application and in the patents documents incorporated herein by reference. Proximal end of lavage catheter  1900  is detachably connected to a irrigation and suction apparatus  1918 . Irrigation and suction apparatus  1918  provides lavage fluid  1916  to lavage catheter  1900  and also provides suction to remove lavage fluid  1916  from the EAC. Lavage catheter  1900  may similarly be used to diagnose or treat other paranasal sinuses, lachrymal ducts, ducts of salivary glands, Eustachian tubes, and other hollow organs in the ear, nose, throat or mouth. 
       FIG. 21  shows a perspective view of a cutting device comprising cutting jaws. Cutting device  2000  comprises a shaft  2002  comprising an upper jaw  2004  and a lower jaw  2006  located on the distal end of shaft  2002 . Proximal region of shaft  2002  comprises a scissor-like device with handles or other suitable control apparatus  2008  that is useable to control the movement of upper jaw  2004  and/or lower jaw  2006 . Upper jaw  2004  and lower jaw  2006  are hinged together so that they can be opened or closed by scissor handles  2008  to bite, grip or cut tissue. In one embodiment, the edges of upper jaw  2004  and lower jaw  2006  are provided with a series of cutting teeth. Alternately, the edges of upper jaw  2004  and lower jaw  2006  may be provided with sharp edges, blunt gripping teeth etc. Shaft  2002  comprises a lumen  2010 . This enables cutting device  2000  to be advanced over an access device such as a guidewire to access a target anatomical region. Examples of materials that can be used to construct cutting device  2000  are stainless steel 304, stainless steel 316, titanium, titanium alloys etc. 
       FIG. 21A  shows a perspective view of the distal region of the cutting device of  FIG. 21  wherein the cutting jaws are closed. 
       FIG. 21B  shows a perspective view of one embodiment of the jaws of the cutting device of  FIG. 21 . Upper jaw  2004  comprises an upper jaw notch  2012 . In one embodiment, upper jaw notch  2012  is semicircular in shape. Similarly, lower jaw  2006  comprises a lower jaw notch  2014 . In one embodiment, lower jaw notch  2014  is semicircular in shape. This design enables a guidewire to pass through a gap in the distal end of the cutting device  2000  even when upper jaw  2004  and lower jaw  2006  are closed. In another embodiment, a guidewire passes through an opening located on either upper jaw  2004  or lower jaw  2006 . Upper jaw  2004  and lower jaw  2006  can also be square, ovoid, trapezoidal or circular in shape. 
       FIG. 21C  shows a crossectional view of the cutting device in  FIG. 21  through plane  21 C- 21 C. Shaft  2002  of cutting device  2000  comprises a lumen  2010  for an access device such as a guidewire. Shaft  2002  further comprises one or more pull wires  2016  that connect upper jaw  2004  and lower jaw  2006  to control apparatus  2008 . When the control apparatus  2008  is moved, pull wires  2016  transmit the movement to upper jaw  2004  and lower jaw  2006  causing them to open or close. 
       FIG. 22A  shows a perspective view of an alternate embodiment of a device comprising cutting or gripping jaws. Cutting device  2100  comprises a shaft  2102 . Distal end of cutting device  2100  comprises an upper jaw  2104  and a lower jaw  2106  that are hinged together at a first hinge  2108 . Proximal end of upper jaw  2104  comprises a first elongate member  2110  and proximal end of second jaw  2106  comprises a second elongate member  2112 . The proximal end of first elongate member  2110  is connected to a second hinge  2114  which in turn is connected to a third elongate member  2116 . Proximal end of second elongate member  2112  is connected to a third hinge  2118  which in turn is connected to a fourth elongate member  2120 . The proximal ends of third elongate member  2116  and fourth elongate member  2120  are connected by a fourth hinge  2122  to pull wire  2124  that passes through shaft  2102 .  FIG. 22A  shows cutting device  2100  wherein the upper jaw  2104  and lower jaw  2106  are in an open configuration. When pull wire  2124  is pulled in the proximal direction, fourth hinge  2122  is pulled inside shaft  2102 . This causes the distal ends of third elongate member  2116  and fourth elongate member  2120  to come closer to each other. This in turn causes the proximal ends of first elongate member  2110  and second elongate member  2112  to come closer to each other. This in turn causes upper jaw  2104  and lower jaw  2106  close. Similarly, pushing pull wire  2124  in the distal direction causes upper jaw  2104  and lower jaw  2106  to open. In one embodiment, cutting device  2100  comprises a spring mechanism located between pull wire  2124  and shaft  2102  that biases upper jaw  2104  and lower jaw  2106  in an open or closed configuration. 
       FIG. 22B  shows a perspective view of the device of  FIG. 22A  wherein the jaws of the cutting device are in a closed configuration. 
       FIGS. 23A-23C  show the various steps of a method of puncturing an anatomical region using a flexible, rotating drill shaft. In  FIG. 23A , an access catheter  2200  is introduced through a nostril to a location adjacent to an anatomical region  2202  to be punctured. In this example, anatomical region  2202  is a maxillary sinus having a maxillary sinus ostium  2204 . Other examples of the types of anatomical regions  2202  are other paranasal sinuses, lachrymal ducts, bony structures in the ear, nose, throat or mouth etc. Access catheter  2200  can be made of suitable biocompatible materials having a sufficient stiffness such as malleable stainless steel tubes; titanium tubes; fully annealed stainless steel tubes; copper tubes; aluminum tubes; tubular elements made of Pebax, HDPE etc. comprising a hypotube; etc. One or more regions of access catheter  2200  may be shapeable or malleable to allow a user to adjust the shape of access catheter  2200  to a patient&#39;s unique anatomy. A substantially stiff access catheter  2200  can be used in situations where extra support is needed for introduction or removal or devices through access catheter  2200 . In an embodiment, a lubricious coating e.g. a Teflon coating is present on the inner surface of access catheter  2200 . The lubricious coating can be made of suitable lubricious materials such as Teflon. In  FIG. 23B , a flexible drill shaft  2206  is introduced through access catheter  2200 . Access catheter  2200  helps to align flexible drill shaft  2206  in the anatomical region  2202  in a desired orientation. Flexible drill shaft  2206  can be designed for efficient transfer of unidirectional or bidirectional torque. Flexible drill shaft  2206  can be made from a suitable material having a high torsional stiffness such as heat treated spring steel. Proximal end of flexible drill shaft  2206  is connected to a reversible drive motor that is used to rotate flexible drill shaft  2206  at a desired angular velocity. Flexible drill shaft  2206  comprises a drill bit  2208  located on the distal end of flexible drill shaft  2206 . Drill bit  2208  can range from 0.5 mm-5 mm in diameter. Drill bit  2208  may be made from suitable materials such as tungsten carbide, carbon steel, diamond powder coated metal etc. Drill bit  2208  can have a drill bit design such as twist drill bit, masonry drill bit, spur point bit, step drill bit etc. Flexible drill shaft  2206  is introduced through access catheter  2202  till drill bit  2208  touches a target location on anatomical region  2202  to be punctured. In  FIG. 23C , flexible drill shaft  2206  is rotated so that drill bit  2208  punctures anatomical region  2202 . Such a method and device can be used for a minimally invasive puncturing of suitable anatomical regions for drainage, aeration, introduction of diagnostic or therapeutic devices etc. Such a device and method can also be used for enlarging or clearing natural or artificial openings in anatomical regions. After a desired opening is created or enlarged, access catheter  2200  and flexible drill shaft  2206  are withdrawn from the anatomy. In one embodiment, flexible drill shaft  2206  is a non-rotating shaft having high column strength and comprising a puncturing tip at the distal end of flexible drill shaft  2206 . In another embodiment, flexible drill shaft  2206  acts as an ultrasonic drill by connecting the proximal end of flexible drill shaft to an ultrasonic generator. In another embodiment, access catheter  2200  comprises one or more bearings that reduce friction between access catheter  2200  and flexible drill shaft  2206 . 
       FIG. 23D  shows a sectional view of an embodiment of a drilling device. Drilling device  2220  comprises a shaft  2222  comprising a proximal rigid portion  2224  and a distal rigid portion  2226 . Shaft  2222  may comprise a deformable (e.g., corrugated, plastically deformable, malleable, etc.) portion  2228  between proximal rigid portion  2224  and distal rigid portion  2226 . Plastically deformable region  2228  allows the shape of drilling device  2220  to be adjusted to facilitate advancement of the device through tortous anatomy, to access to a target anatomical location and/or to achieve a desired positioning or attitude of the bit  2230  within the subject&#39;s body. Proximal rigid portion  2224 , distal rigid portion  2226  and plastically deformable or malleable region  2228  can be made of suitable biocompatible materials such as stainless steel e.g. fully annealed stainless steel, copper, aluminum etc. Drilling device  2220  further comprises a rotating drill bit  2230  located at distal end of a rotatable drive member of shaft  2222 . Rotating drill bit  2230  can be made from suitable materials such as tungsten carbide, carbon steel, diamond powder coated metal etc. Rotating drill bit  2230  can be an abrasive coated spherical ball or a twist (e.g., helical) drill bit, masonry drill bit, spur point bit, step drill bit etc. Proximal region of rotating drill bit  2230  is in contact with distal end of shaft  2222 . In order to reduce friction between rotating drill bit  2230  and shaft  2222 , the contact surfaces between rotating drill bit  2230  and shaft  2222  comprise a lubricious coating e.g. a Teflon coating. Proximal region of rotating drill bit  2230  is also attached to a flexible drive shaft  2232  that supplies torque to the rotating drill bit  2230 . In one embodiment, flexible drive shaft  2232  comprises a coil assembly with high torsional stiffness and column strength. In another embodiment, flexible drive shaft  2232  comprises a heat treated spring steel cable. Proximal end of flexible drive shaft  2232  is connected to a reversible drive motor. In one embodiment, rotating drill bit  2230  and flexible drive shaft  2232  comprise a coaxial lumen to enable drilling device  2220  to be introduced over a guidewire into a target anatomy. Such a device can be used for a minimally invasive puncturing of suitable anatomical regions for drainage, aeration, introduction of diagnostic or therapeutic devices etc. Such a device can also be used for enlarging or clearing natural or artificial openings in anatomical regions. It will be appreciated by those of skill in the art that, although this device  2220  is referred to herein as a “drilling device” it may be used for numerous purposes other than “drilling.” For example, this device  2220  may be used to cut, grind, polish or create grooves or depressions in bone, cartilage or other tissue and/or may be used as a screw driver. Thus, in some applications, this drilling device  2220  may alternatively be aptly referred to as a cutter, grinder, rotating rasp, rotating brush, dremmel, polisher, burnisher, boring tool, grooving tool, etc. Also, in some embodiments, the bit may comprise a drive bit that is useable to drive a permanent or resorbable bone screw or other type of screw or anchor. Also, the bit  2230  may be interchangeable and a variety of different bits  2220  may be provided to accomplish various different applications (e.g., grinding, polishing, burnishing, grooving, boring, rasping, debulking, forming indentations or depressions, driving screws, etc.).  FIGS. 24A-24C  show a sagittal section of an Ethmoid sinus showing various methods of treating Ethmoid sinus diseases by a minimally invasive approach.  FIG. 24A  shows a sagittal section of an Ethmoid sinus comprising an anterior Ethmoid air cell  2300 , a posterior Ethmoid air cell  2302  and an intermediate Ethmoid air cell  2304  located between anterior Ethmoid air cell  2300  and posterior Ethmoid air cell  2302 . A guide catheter  2306  is introduced to a region inferior to the basal lamella of a middle turbinate. Guide catheter  2306  may comprise a design selected from the various guide catheter designs disclosed herein and in the patent documents incorporated herein by reference. Thereafter, an introducer needle  2308  is introduced through guide catheter  2306 . Introducer needle  2308  comprises a lumen through which devices such as guidewires can be introduced. Introducer needle  2308  can be made of suitable biocompatible materials such as Stainless steel, Nitinol, polymers, polymer-metal composites etc. Introducer needle  2308  is advanced through guide catheter  2306  such that the distal tip of introducer needle  2308  punctures a wall of an Ethmoid air cell e.g. anterior Ethmoid air cell  2300  and enters the Ethmoid air cell. Thereafter, a guidewire  2310  is introduced through introducer needle  2308  into the Ethmoid air cell e.g. anterior Ethmoid air cell  2300 . Thereafter, introducer needle  2308  is removed from the anatomy. In  FIG. 24B , a working device is introduced over guidewire  2310  into the Ethmoid air cell. An example of a working device is a balloon catheter  2312  comprising a dilating balloon  2314 . Thereafter, the working device is used to perform a diagnostic or therapeutic procedure e.g. balloon dilation of the introducer needle puncture site to create a drainage channel for sinus secretions. Similarly, other working devices such as dilating or occluding balloons, dilating stents, suction or irrigation devices, needles, polypectomy tools, brushes, energy emitting devices such as ablation devices, laser devices, image-guided devices containing sensors or transmitters, imaging devices, endoscopes, tissue modifying devices such as cutters, biopsy devices, devices for injecting diagnostic or therapeutic agents, lavage devices, drug delivery devices such as substance eluting devices, substance delivery implants etc. may be used to perform diagnostic or therapeutic procedures. The method shown in  FIGS. 24A-24B  may also be used to create an opening of a suitable diameter to facilitate insertion of other working devices into the Ethmoid air cells. For example,  FIG. 24C  shows a method of treating Ethmoid sinus diseases by a rongeur. In this method, rongeur  2316  having a distal cutting tip  2318  is introduced through guide catheter  2306  into an Ethmoid air cell via the introducer needle puncture site. Thereafter, rongeur  2316  is used to remove tissue from the Ethmoid air cell. 
     FIGS.  24 A′- 24 A″″ show a method of creating drainage channels for sinus secretions in Ethmoid sinus. In FIG.  24 A′, guide catheter  2306  is introduced to a region inferior to the basal lamella of a middle turbinate. Thereafter, introducer needle  2308  is advanced through guide catheter  2306  such that the distal tip of introducer needle  2308  punctures a wall of an Ethmoid air cell e.g. an intermediate Ethmoid air cell  2304  and enters the Ethmoid air cell. In FIG.  24 A″, introducer needle is used to create internal channels in the Ethmoid sinus by puncturing walls of adjacent Ethmoid air cells e.g. anterior Ethmoid air cell  2300 , posterior Ethmoid air cell  2302  etc. In FIG.  24 A′″, introducer needle  2308  and guide catheter  2306  are removed leaving behind internal channels that allow drainage of sinus secretions through the introducer needle puncture site in the intermediate Ethmoid air cell  2304 . Sinus secretions from anterior Ethmoid air cell  2300  or posterior Ethmoid air cell  2302  flow into intermediate Ethmoid air cell  2304  from which they flow out of the Ethmoid sinus. The internal channels as well as the introducer needle puncture site in the intermediate Ethmoid air cell  2304  may be dilated using a balloon catheter as shown in  FIGS. 24A-24B . In FIGS.  24 A′- 24 A′″, introducer needle  2308  was introduced into the Ethmoid sinus through intermediate Ethmoid air cell  2304 . Similar procedures may be performed by introducing introducer needle  2304  into the Ethmoid sinus through anterior Ethmoid air cell  2300  or posterior Ethmoid air cell  2302 . In one embodiment, anterior Ethmoid air cell  2300 , posterior Ethmoid air cell  2302  and intermediate Ethmoid air cell  2304  are punctured separately through the basal lamella of a middle turbinate to create separate drainage channels for each Ethmoid air cell as shown in FIG.  24 A″″. 
       FIG. 25A  shows a perspective view of an embodiment of a microshaver or ostium enlarger device  2400 . Device  2400  comprises a proximal portion  2402  and a distal portion  2403 . Proximal portion  2402  is hollow and comprises a proximal cutting surface  2404  e.g. sharp cutting teeth etc. located on the distal end of proximal portion  2402 . Distal portion  2403  comprises a distal cutting surface  2406  e.g. sharp cutting teeth etc. located on the proximal end of distal portion  2403 . Distal portion  2403  is further connected to a pull shaft  2408  that encloses a guidewire lumen  2410 . Guidewire lumen  2410  allows microshaver  2400  to be introduced over a guidewire GW into a target anatomy. The region between pull shaft  2408  and proximal portion  2402  encloses a suction lumen  2412 . Suction lumen  2412  can be used to remove solid debris or liquids from the target anatomy by suction. Proximal portion  2402 , distal portion  2403  and pull shaft  2408  can be made of suitable biocompatible materials such as stainless steel. 
       FIG. 25B  shows a crossection of a paranasal sinus showing one way in which the device  2400  of  FIG. 25A  may be used to remove tissue or matter. The device  2400  is introduced over a guidewire GW into paranasal sinus  2414 . The device  2400  is then positioned such that the tissue or matter is located between proximal cutting surface  2404  and distal cutting surface  2406 . Thereafter, in this embodiment, pull shaft  2408  is pulled in the proximal direction. This causes movement of distal region  2403  in the proximal direction with respect to proximal portion  2402 . This in turn forces cylindrical distal cutter  2406  to be retracted into the interior of the cylindrical proximal cutter  2404 , thereby cutting off or breaking tissue or matter that is captured therebetween. Optionally, in this embodiment, the cylindrical distal cutter  2406  cylindrical proximal cutter  2404  may be rotated relative to the other to further cut or shave tissue. Also, optionally in this embodiment, suction lumen  2412  can be used to remove any solid debris or liquids generated during the procedure. 
       FIGS. 25C and 25D  show an example of another way in which the device  2400  may be used—i.e., to shave tissue or matter. Examples of anatomical structures that may be shaved by this device  2400  include bone, cartilage and soft tissues of Eustachian tubes, turbinates, lachrymal ducts, anatomical openings such as ostia of paranasal sinuses, ostia of lachrymal ducts, etc. and other regions in the ear, nose, throat or mouth. As shown in  FIG. 25C , in this embodiment, there need not be a proximally moveable pull shaft  2408 , but rather the distal cutting surface  2406  may remain positioned within the cylindrical proximal cutting surface  2404 . The cuffing surfaces are positioned adjacent to the tissue or matter to be shaved and the cylindrical distal cutter  2406  and/or cylindrical proximal cutter  2404  is/are rotated to shave the tissue or matter. Suction may be applied through lumen  2412  to draw the tissue or matter into slots  2409  such that it will be shaved by the rotating proximal cutter  2404 . 
       FIGS. 26A-26C  show a device and method for treating a mucocyst of other flowable substance-containing structure (e.g., cyst, hematoma, pustule, etc.) located within a paranasal sinus, ear, nose or throat. In general, the device comprises an elongate shaft  2500 , a penetrator such as a needle  2502  that is advanceable from and retractable into the shaft  2500  to form an opening in the mucocyst or other structure, and a compressor such as a balloon  2506  that is useable to compress the mucocyst or other structure to force its contents to flow out of the opening created by the needle  2502  or other penetrator. Specifically, as shown in the example of  FIG. 26A , a guide catheter  2500  is introduced into an anatomical region through an anatomical opening. The outer diameter of guide catheter  2500  is less than the inner diameter of the anatomical opening. In  FIGS. 26A-26C , frontal sinus FS is used as an example of an anatomical region. Other examples of anatomical regions are other paranasal sinuses, lachrymal passages, Eustachian tubes and other structures in the ear, nose, throat or mouth etc. Guide catheter  2500  may comprise a design selected from the various guide catheter designs disclosed herein and in the patent documents incorporated herein by reference. A puncturing needle  2502  is then introduced through guide catheter  2500  into the frontal sinus FS. Puncturing needle  2502  has a sharp distal tip and can be made from a variety of materials such as hardened tool steel, stainless steel etc. Puncturing needle  2502  is navigated through the frontal sinus FS such that the distal tip of puncturing needle  2502  punctures a mucocyst  2503  in the frontal sinus FS. Thereafter, puncturing needle  2502  is withdrawn. In  FIG. 26B , a guidewire GW is introduced into the frontal sinus FS. Thereafter, a balloon catheter  2504  comprising a balloon  2506  is introduced over guidewire GW into the frontal sinus FS. Balloon  2506  can be made of suitable compliant or semi-compliant materials such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon, etc. Balloon  2506  is then inflated. Inflated balloon  2506  compresses the punctured mucocyst  2503 . This causes drainage of mucocyst secretions into the frontal sinus FS. In  FIG. 26C , balloon  2506  is inflated further so that it occupies a volume in the frontal sinus FS and displaces the mucocyst secretions from the frontal sinus FS out through the frontal sinus ostium FSO. 
       FIGS. 27A-27B  show various steps of a method of treating a mucocyst by a balloon catheter comprising a deployable puncturing needle. In  FIG. 27A , a guide catheter  2600  is introduced into an anatomical region through an anatomical opening. The outer diameter of guide catheter  2600  is less than the inner diameter of the anatomical opening. In  FIGS. 27A-27B , frontal sinus FS is used as an example of an anatomical region. Other examples of anatomical regions are other paranasal sinuses, lachrymal passages, Eustachian tubes, other ear, nose, throat and mouth structures etc. Guide catheter  2600  may comprise a design selected from the various guide catheter designs disclosed herein and in the patent documents incorporated herein by reference. A balloon catheter  2602  comprising a balloon  2604  and a deployable puncturing needle  2606  is then introduced through guide catheter  2600  into the frontal sinus FS. Balloon  2604  can be made of suitable compliant or semi-compliant materials such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon, etc. Deployable puncturing needle  2606  can be made from a variety of materials such as hardened tool steel, stainless steel etc. Balloon catheter  2604  is oriented in a desired orientation and deployable puncturing needle  2606  is advanced such that the distal tip of deployable puncturing needle  2606  punctures the mucocyst MC. Thereafter, deployable puncturing needle  2606  is withdrawn into balloon catheter  2602 . In  FIG. 27B , balloon  2604  is inflated. Inflated balloon  2604  compresses the punctured mucocyst MC. This causes drainage of mucocyst secretions into the frontal sinus FS. Balloon  2604  is then inflated further so that it occupies a volume in the frontal sinus FS and displaces the mucocyst secretions from the frontal sinus FS out through the frontal sinus ostium FSO. In one embodiment, deployable puncturing needle  2606  is located in a needle lumen. Deployable puncturing needle  2606  may be advanced or withdrawn by advancing or withdrawing deployable puncturing needle  2606  through the needle lumen. 
       FIGS. 28A-28C  show various embodiments of catheters comprising agent delivery needles. In  FIG. 28A , catheter  2700  comprises a shaft  2702  having a guidewire lumen. Catheter  2700  further comprises a deployable injecting needle  2704  made from suitable biocompatible materials such as stainless steel. Deployable injecting needle  2704  comprises a lumen for injecting one or more diagnostic or therapeutic agents  2706  into the adjacent anatomy. Deployable injecting needle  2704  is deployed at any suitable angle to the longitudinal axis of shaft  2702 , for example such angle may range from 0 degrees to 135 degrees. In one embodiment, deployable injecting needle  2704  is located in a needle lumen. Deployable injecting needle  2704  is deployed or withdrawn by relative motion of deployable injecting needle  2704  with respect to shaft  2702 . In another embodiment, deployable injecting needle  2704  can be deployed or withdrawn by inflating or deflating a deploying balloon. The deploying balloon can be made from suitable materials such as polyimide, parylene (e.g. C,D,N), silicone, polyurethane, polyethylene terephthalate etc. Catheter  2700  is introduced into a target anatomy and deployable injecting needle  2704  is deployed. Deployable injecting needle  2704  penetrates into the adjacent anatomy. One or more diagnostic or therapeutic agents  2706  are then injected into the adjacent anatomy. In one embodiment, catheter  2700  may be introduced in an anatomical region through a guide catheter  2708 .  FIG. 28B  shows a perspective view of catheter  2700  of  FIG. 28A  wherein catheter  2700  further comprises a second deployable injecting needle  2710 . Second deployable injecting needle  2710  comprises a lumen for injecting one or more diagnostic or therapeutic agents  2712  into the adjacent anatomy. In one embodiment, diagnostic or therapeutic agents  2712  are the same as diagnostic or therapeutic agents  2706 .  FIG. 28C  shows a perspective view of catheter  2700  of  FIG. 28A  wherein catheter  2700  further comprises a balloon  2714 . In one embodiment, balloon  2714  is a dilating balloon made of suitable non-compliant materials e.g. polyethylene terephthalate etc. This embodiment can be used for both balloon dilation and agent delivery. In another embodiment, balloon  2714  is an anchoring balloon made of suitable non-compliant materials e.g. polyethylene terephthalate etc. or suitable compliant or semi-compliant materials such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. The anchoring balloon can be used to stabilize the position and orientation of catheter  2700  before agent delivery. 
     Examples of diagnostic or therapeutic agents that can be delivered by the catheters in  FIGS. 28A-28C  are pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), an anesthetic agent with or without a vasoconstriction agents (e.g. Xylocaine with or without Epinephrine, Tetracaine with or without epinephrine, etc.), an analgesic agent, a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, hemostatic agents to stop bleeding, anti-proliferative agents, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations, viral vectors carrying DNA, proteins or mRNA coding for important therapeutic functions or substances etc. Catheters in  FIGS. 28A-28C  can be used to diagnose or treat anatomical regions such as paranasal sinuses, regions in the Eustachian tubes, lachrymal ducts, ducts of salivary glands, anatomical openings such as ostia of paranasal sinuses, ostia of lachrymal ducts, other regions in the ear, nose, throat or mouth etc. 
       FIG. 29A  illustrates an embodiment of a displacement catheter to displace and remove secretions in an anatomical region. Displacement catheter  2800  comprises an outer sheath  2802  that encloses a balloon catheter  2804 . Outer sheath  2802  may be flexible or substantially rigid. Outer sheath  2802  may be made of suitable materials such as Pebax, HDPE etc. Outer sheath  2802  may comprise a hypotube made of suitable biocompatible materials such as stainless steel, Nitinol etc. Balloon catheter  2804  comprises a catheter shaft  2806  and a balloon  2808  located on the distal region of catheter shaft  2806 . Catheter shaft  2806  may be made of suitable materials such as Pebax, HDPE etc. Balloon  2808  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. 
       FIG. 29B  shows a sectional view of an anatomical region showing a method of displacing secretions by the displacement catheter of  FIG. 29A . Displacement catheter  2800  is introduced in an anatomical region. In  FIG. 29B , a Maxillary sinus MS is used as an example of an anatomical region. Other examples of anatomical regions that can be treated using displacement catheter  2800  are other paranasal sinuses, lachrymal passages, Eustachian tubes etc. Displacement catheter  2800  can be advanced into an anatomical region through natural openings e.g. ostia of sinuses or artificially created openings. In this example, displacement catheter  2800  is advanced into the Maxillary sinus through a natural opening such as a maxillary sinus ostium MSO such that the distal end of displacement catheter is near the distal region of Maxillary sinus MS. Outer diameter of outer sheath  2802  is less than inner diameter of Maxillary sinus ostium MSO. Thereafter, outer sheath  2802  is withdrawn gradually by pulling outer sheath  2802  in the proximal direction over balloon catheter  2804 . Simultaneously, balloon  2808  is inflated by a suitable inflating medium such as saline mixed with radiographic contrast. This causes distal region of balloon  2804  to inflate before the proximal region of balloon  2804 . Balloon  2804  gradually begins to occupy available volume in the Maxillary sinus MS and thus displaces secretions  2810  out of the Maxillary sinus MS through the Maxillary sinus ostium MSO. In one embodiment of balloon  2804 , distal region of balloon  2804  has a higher compliance than proximal regions of balloon  2804 . In another embodiment, balloon  2804  comprises multiple compartments such that each compartment can be inflated independently of other compartments. Balloon  2804  may be detachably connected to catheter shaft  2806  to enable permanent occlusion of the anatomical region. Balloon  2804  may also comprise a variety of drug delivery mechanisms including drug eluting coatings, drug eluting pores for eluting a drug dissolved in the inflating medium etc. 
       FIG. 30  shows a perspective view of an embodiment of an ultrasonic drilling device. Drilling device  2900  comprises a rigid or flexible drilling shaft  2902 . Drilling shaft  2902  can be made of suitable materials such as tungsten carbide flexible wire. The proximal end of drilling shaft  2902  is connected to a piezoelectric crystal  2904  such as a quartz (SiO2) or barium titanate (BaTiO3) crystal. Piezoelectric crystal  2904  may have a layer of backing material  2906  on the proximal surface of piezoelectric crystal  2904 . Piezoelectric crystal  2904  is connected by electrodes  2908  to an electric power source  2910 . Electric power source  2910  delivers a suitable current via electrodes  2908  to piezoelectric crystal  2904  to cause piezoelectric crystal  2904  to vibrate at an ultrasonic frequency. The vibration of piezoelectric crystal  2904  is transmitted to drilling shaft  2902 . In one embodiment, drilling shaft  2902  is connected to piezoelectric crystal  2904  by a coupler  2912 . 
       FIGS. 30A-30B  show a sectional view of an anatomical region showing a method of enlarging a natural or artificially created anatomical opening using the drilling device of  FIG. 30 . The drilling device may also be used to create new openings in an anatomical region. Distal part of drilling device  2900  comprising drilling shaft  2902  of diameter D.sub.2 is positioned such that the distal end of drilling shaft  2902  touches an anatomical opening e.g. a sphenoid sinus ostium SSO to be dilated. The anatomical opening has an initial diameter D.sub.1. Thereafter, current from electric power source  2910  is switched on, which in turn causes drilling shaft  2902  to vibrate in the axial direction. The vibration of drilling shaft  2902  causes distal tip of drilling shaft  2902  to impact the anatomical opening. In  FIG. 30B , the impact of drilling shaft  2902  causes dilation of the anatomical opening from an initial diameter D.sub.1 to a diameter D.sub.2. 
     Similarly, other embodiments of drilling devices may be used to puncture, remodel or change the shape, size or configuration of anatomical structures such as paranasal sinuses, Eustachian tubes, middle ear, nasopharynx, Lachrymal ducts or other anatomical regions in the ear, nose, throat or mouth. Such drilling devices may comprise for example elements for ablation or delivery of energy such as laser, RF, thermal shock waves etc. 
       FIG. 31  shows a sectional view of an embodiment of a catheter for providing an internal cast for fractured bony cavities. Catheter  3000  comprises a shaft  3002  comprising a plurality of inflating elements e.g. inflating balloon in the distal region of shaft  3002 . In the example shown in  FIG. 31 , catheter  3000  comprises a proximal interior balloon  3004 , a distal interior balloon  3006  and an intermediate interior balloon  3008  located between proximal interior balloon  3004  and distal interior balloon  3006 . Catheter  3000  further comprises an intermediate balloon  3010  covering proximal interior balloon  3004  and intermediate interior balloon  3008  as shown in  FIG. 31 . Catheter  3000  further comprises an outer balloon  3012  that covers intermediate balloon  3010  and a portion of distal interior balloon  3006  as shown in  FIG. 31 . The balloons on catheter  3000  can be inflated independently of each other. For example proximal interior balloon  3004  can be inflated by a proximal interior balloon lumen  3014 , distal interior balloon  3006  can be inflated by a distal interior balloon inflation lumen  3016  and intermediate interior balloon  3008  can be inflated by an intermediate balloon inflation lumen  3018 . The balloons on catheter  3000  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. or from suitable non-compliant materials e.g. polyethylene terephthalate etc. The balloons on catheter  3000  may be coated with a variety of coatings including lubricious coatings, drug eluting coatings etc.  FIG. 31A  shows a crossection through the outer balloon  3012  in the catheter  3000  of  FIG. 31  through plane  31 A- 31 A. Outer balloon  3012  comprises a balloon material  3020  made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. or from suitable non-compliant materials e.g. polyethylene terephthalate etc. A coating  3022  is located on the outer surface of balloon material  3020 . Examples of materials that can be used in coating  3022  are contrast agents, pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), an anesthetic agent with or without a vasoconstriction agents (e.g. Xylocaine with or without Epinephrine, Tetracaine with or without epinephrine, etc.), an analgesic agent, a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, hemostatic agents to stop bleeding, anti-proliferative agents, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations etc. 
       FIGS. 31B-31D  shows various steps of a method of providing an internal cast for a fractured bony cavity using the catheter shown in  FIG. 31 . In  FIGS. 31B-31D , Maxillary sinus MS is used as an example of bony cavity that can be treated using catheter  3000 .  FIG. 31B  shows a patient with a fractured bony cavity e.g. a fractured Maxillary sinus MS having one or more fractured bones  3024 . In  FIG. 31C , catheter  3000  is introduced into the Maxillary sinus MS through a natural opening e.g. an ostium or an artificially created opening. In  FIG. 31D , one or more balloons on catheter  3000  are sequentially inflated to push fractured bones  3024  into their original un-fractured configuration. Catheter  3000  may then be left in place for a desired period ranging from a few minutes to several days during which fractured bones  3024  begin to heal in their original un-fractured configuration. After catheter  3000  has been left in place for the desired period, catheter  3000  is removed by deflating the balloons and withdrawing catheter  3000  from the anatomy. Thus, catheter  3000  provides an internal cast for a fractured bony cavity. Various embodiments of catheter  3000  may be used for crating internal casts for fractured paranasal sinuses, lachrymal passages, Eustachian tubes, other structures in the ear, nose, throat, mouth etc. 
     The various devices and methods disclosed herein may be used in conjunction with various surgical navigations systems.  FIGS. 32 and 32A  show an embodiment of a surgical navigation system comprising electromagnetic sensors. Examples of electromagnetic sensors that can be used with the present invention are electromagnetic sensors of an electromagnetic surgical navigation system such as GE InstaTrak™ 3500 plus system etc.  FIG. 32  shows a perspective view of a patient&#39;s head showing the location of external ear canal electromagnetic sensors  3100  and teeth electromagnetic sensors  3102 . External ear canal electromagnetic sensors  3100  are introduced through an ear canal into a region adjacent to a tympanum. Teeth electromagnetic sensors  3102  are attached to one or more teeth of the patient. In one embodiment, teeth electromagnetic sensors  3102  are attached to teeth using an adhesive. In an alternate embodiment, teeth electromagnetic sensors  3102  are attached to braces or caps which in turn are attached to teeth. The braces or caps can be made of suitable materials that cause minimal artifacts on CT or MRI images. An example of such a material is aluminum alloy 2017-T4 which causes minimal artifacts on a CT scan image. Other locations of electromagnetic sensors include skin (e.g. a skin patch comprising an electromagnetic sensor), a head frame etc. The patient&#39;s head is imaged using an imaging modality such as CT or MRI. External ear canal electromagnetic sensors  3100  and teeth electromagnetic sensors  3102  are passively imaged by the imaging modality and thus act as fiducial markers. 
       FIGS. 32 and 32A  illustrate a surgical navigation system comprising fiducial markers that have electromagnetic sensors. Various other embodiments of fiducial markers such as passively imaged fiducial markers or active sensors or transmitters may be used in conjunction with the various methods and devices disclosed herein. The fiducial markers may be located on relevant anatomical regions such as teeth, ear canals, skull bones, frames fixed to rigid bones etc. The fiducial markers may be used with a variety of modalities including but not limited to electromagnetic, infrared, ultrasonic, radio-frequency, MRI, CT, Fluoroscopic or other 2D or 3D image guided systems for the head, neck or other anatomical regions manufactured by companies such as Biosense, Stryker, Brainlab, Xomed, GE/VTI etc. 
       FIG. 32A  shows an enlarged view of region  32 A in  FIG. 32 . Teeth electromagnetic sensors  3102  are connected to the electromagnetic surgical navigation system by removable leads  3104 . In another embodiment, external ear canal electromagnetic sensors  3100  or teeth electromagnetic sensors  3102  are connected to the electromagnetic surgical navigation system by telemetry. During a procedure, external ear canal electromagnetic sensors  3100  and/or teeth electromagnetic sensors  3102  are actively imaged by suitable electromagnetic surgical navigation systems such as GE InstaTrak™ 3500 plus system etc. Thereafter, data from imaging modality such as CT or MRI and the electromagnetic surgical navigation system is merged to obtain a three dimensional map of the anatomy showing the electromagnetic sensors. The three dimensional map can then be used for image guided procedures such as diagnostic or therapeutic procedures of paranasal sinuses, Eustachian tubes, lachrymal ducts, other ear, nose, throat or mouth structures etc. 
     Other image guided surgery systems such as infrared sensor based systems e.g. Stryker Leibinger® Navigation System can also be used in conjunction with one or more methods or devices disclosed herein. 
       FIG. 33  shows a section of the anatomical region around a Eustachian tube (ET) showing a diagnostic or therapeutic procedure being performed by devices inserted through the pharyngeal ostium of the Eustachian tube.  FIG. 33  shows a guidewire GW inserted into a desired region in the ET through the Nasopharynx and a diagnostic or therapeutic being performed by a device introduced into the Eustachian tube over guidewire GW. 
       FIG. 33A  shows an enlarged view of region  33 A in  FIG. 33  showing the anatomical region around a Eustachian tube (ET) showing a diagnostic or therapeutic procedure being performed by devices inserted through the pharyngeal ostium of the Eustachian tube. In one embodiment, guidewire GW comprises an anchoring balloon  3200  located on the distal region of guidewire GW. Anchoring balloon  3200  is inflated after positioning guidewire GW at a target location. Anchoring balloon  3200  anchors guidewire GW to the adjacent anatomy and prevents accidental repositioning of guidewire GW during a diagnostic or therapeutic procedure. Anchoring balloon  3200  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. Guidewire GW may comprise anchoring elements other than anchoring balloon  3200  such as a notch on guidewire GW, a bent region on guidewire GW, a self expanding element, a hook, a coiled element etc. In another embodiment, guidewire GW comprises a sensor  3202  located on the distal region of guidewire GW. Sensor  3202  enables guidewire GW to be used in conjunction with a suitable surgical navigation system. In one embodiment, sensor  3202  is an electromagnetic sensor used in conjunction with an electromagnetic surgical navigation system such as GE InstaTrak™ 3500 plus system etc. One or more sensor  3202  or other types of surgical navigation sensors or transmitters may also be located on other diagnostic or therapeutic devices disclosed herein. Sensor  3202  may be used in conjunction with a stationary sensor  3204  located in the external ear. The combination of sensor  3202  and stationary sensor  3204  enables guidewire GW to be accurately positioned in a target region. In an embodiment, a radiopaque plug  3206  is inserted from the external ear to a region adjacent to an eardrum. Radiopaque plug  3206  serves as a fiducial marker during preoperative scanning of the patient and thus enables a physician to accurately position a diagnostic or therapeutic device close to the eardrum. Other image guidance methods and devices can also be used in conjunction with diagnostic or therapeutic procedures disclosed herein.  FIG. 33A  also shows a diagnostic or therapeutic device  3208  comprising a shaft  3210  and a working element  3212  e.g. a dilating balloon being introduced over guidewire GW. Diagnostic or therapeutic device  3208  may comprise a radiopaque marker  3214 . 
       FIG. 33B  shows a front view of a human head with a portion of the face removed to show an embodiment of a method of introducing a guidewire into a Eustachian tube. In  FIG. 33B , a guide catheter  3250  is introduced through a nostril into the Nasopharynx. Distal portion of guide catheter  3250  may comprise a bent or angled region. For example, such bent or angled region may form e an internal angle ranging from 45 degrees to 150 degrees. Guide catheter  3250  can be constructed using one of the various designs disclosed herein and in the patent documents incorporated herein by reference. Guide catheter  3250  is positioned in the Nasopharynx such that the distal tip of guide catheter  3250  is located near a nasopharyngeal opening of a Eustachian tube. Thereafter, a guidewire GW is introduced through guide catheter  3250  into the Eustachian tube. Guidewire GW can then be used to advance one or more diagnostic or therapeutic devices into the Eustachian tube to perform one or more diagnostic or therapeutic procedures. 
       FIGS. 34A-34D  illustrate various examples of working elements that can be located on the diagnostic or therapeutic device in  FIG. 33 . FIG.  34 A shows an example of a working element comprising a dilating balloon. Dilating balloon  3312  can be made from a suitable non-compliant materials e.g. polyethylene terephthalate, Nylon etc. Similarly, devices shown in  FIGS. 14 ,  15 ,  16 ,  17  and  18  may also be used to treat a Eustachian tube as shown in  FIG. 33 . 
       FIG. 34B  shows an example of a working element comprising a dilating balloon loaded with a balloon-expandable stent. Dilating balloon  3314  can be made from a suitable non-compliant materials e.g. polyethylene terephthalate, Nylon etc. Several types of stent designs can be used to construct stent  3316  such as metallic tube designs, polymeric tube designs, chain-linked designs, spiral designs, rolled sheet designs, single wire designs etc. These designs may have an open celled or closed celled structure. A variety of fabrication methods can be used for fabricating stent  3316  including but not limited to laser cutting a metal or polymer element, welding metal elements etc. A variety of materials can be used for fabricating stent  3316  including but not limited to metals, polymers, foam type materials, plastically deformable materials, super elastic materials etc. A variety of features can be added to stent  3316  including but not limited to radiopaque coatings, drug elution mechanisms to elute anti-inflammatory agents, antibiotics etc. In one embodiment, stent  3316  is bioabsorbable. Working elements may also comprise a self-expanding stent instead of a pressure-expandable stent. 
       FIG. 34C  shows an example of a working element comprising a lavage element. Lavage element  3318  comprises a plurality of lavage openings  3320 . Lavage openings are connected to a lavage lumen in shaft  3210  through which suitable ravage media such as solutions containing contrast agents, pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, anti-parasitic, antifungal, etc.), an anesthetic agent with or without a vasoconstriction agents (e.g. Xylocaine with or without Epinephrine, Tetracaine with or without epinephrine, etc.), an analgesic agent, a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), an allergen or another substance that causes secretion of mucous by tissues, hemostatic agents to stop bleeding, anti-proliferative agents, cytotoxic agents e.g. alcohol, biological agents such as protein molecules, stem cells, genes or gene therapy preparations etc. can be delivered. In one embodiment, a fraction of lavage openings  3320  are connected to an aspiration lumen to aspirate the lavage media out of the Eustachian tube. 
       FIG. 34D  shows an example of a working element comprising a substance delivery reservoir. Substance delivery reservoir  3322  may be fully or partially biodegradable or non-biodegradable. In one embodiment, substance delivery reservoir  3322  is made of a suitable biocompatible material such as hydrogel (e.g. collage hydrogel). In another embodiment, substance delivery reservoir  3322  comprises a porous matrix formed of a porous material such as a flexible or rigid polymer foam, cotton wadding, gauze, etc. Examples of biodegradable polymers that may be foamed or otherwise rendered porous include polyglycolide, poly-L-lactide, poly-D-lactide, poly(amino acids), polydioxanone, polycaprolactone, polygluconate, polylactic acid-polyethylene oxide copolymers, modified cellulose, collagen, polyorthoesters, polyhydroxybutyrate, polyanhydride, polyphosphoester, poly(alpha-hydroxy acid) and combinations thereof. Examples of non-biodegradable polymers that may be foamed or otherwise rendered porous include polyurethane, polycarbonate, silicone elastomers etc. Substance delivery reservoir  3322  may also include one or more embodiments disclosed in U.S. patent application Ser. No. 10/912,578 entitled “Implantable Device and Methods for Delivering Drugs and Other Substances to Treat Sinusitis and Other Disorders” filed on Aug. 4, 2004, the entire disclosure of which is expressly incorporated herein by reference. The substance delivery reservoir  3322  or any substance delivery devices described in this application may be used to deliver various types of therapeutic or diagnostic agents. The term “diagnostic or therapeutic substance” as used herein is to be broadly construed to include any feasible drugs, prodrugs, proteins, gene therapy preparations, cells, diagnostic agents, contrast or imaging agents, biologicals, etc. Such substances may be in bound or free form, liquid or solid, colloid or other suspension, solution or may be in the form of a gas or other fluid or nan-fluid. For example, in some applications where it is desired to treat or prevent a microbial infection, the substance delivered may comprise pharmaceutically acceptable salt or dosage form of an antimicrobial agent (e.g., antibiotic, antiviral, antiparacytic, antifungal, etc.), a corticosteroid or other anti-inflammatory (e.g., an NSAID), a decongestant (e.g., vasoconstrictor), a mucous thinning agent (e.g., an expectorant or mucolytic), an agent that prevents of modifies an allergic response (e.g., an antihistamine, cytokine inhibitor, leucotriene inhibitor, IgE inhibitor, immunomodulator), etc. 
     Some nonlimiting examples of antimicrobial agents that may be used in this invention include acyclovir, amantadine, aminoglycosides (e.g., amikacin, gentamicin and tobramycin), amoxicillin, amoxicillin/clavulanate, amphotericin B, ampicillin, ampicillin/sulbactam, atovaquone, azithromycin, cefazolin, cefepime, cefotaxime, cefotetan, cefpodoxime, ceftazidime, ceftizoxime, ceftriaxone, cefuroxime, cefuroxime axetil, cephalexin, chloramphenicol, clotrimazole, ciprofloxacin, clarithromycin, clindamycin, dapsone, dicloxacillin, doxycycline, erythromycin, fluconazole, foscarnet, ganciclovir, atifloxacin, imipenem/cilastatin, isoniazid, itraconazole, ketoconazole, metronidazole, nafcillin, nafcillin, nystatin, penicillin, penicillin G, pentamidine, piperacillin/tazobactam, rifampin, quinupristin-dalfopristin, ticarcilliniclavulanate, trimethoprim/sulfamethoxazole, valacyclovir, vancomycin, mafenide, silver sulfadiazine, mupirocin (e.g., Bactroban Nasal®, Glaxo SmithKline, Research Triangle Park, N.C.), nystatin, triamcinolonelnystatin, clotrimazole/betamethasone, clotrimazole, ketoconazole, butoconazole, miconazole, tioconazole, detergent-like chemicals that disrupt or disable microbes (e.g., nonoxynol-9, octoxynol-9, benzalkonium chloride, menfegol, and N-docasanol); chemicals that block microbial attachment to target cells and/or inhibits entry of infectious pathogens (e.g., sulphated and sulphonated polymers such as PC-515 (carrageenan), Pro-2000, and Dextrin 2 Sulphate); antiretroviral agents (e.g., PMPA gel) that prevent retroviruses from replicating in the cells; genetically engineered or naturally occurring antibodies that combat pathogens such as anti-viral antibodies genetically engineered from plants known as “plantibodies;” agents which change the condition of the tissue to make it hostile to the pathogen (such as substances which alter mucosal pH (e.g., Buffer Gel and Acidform); non-pathogenic or “friendly” microbes that cause the production of hydrogen peroxide or other substances that kill or inhibit the growth of pathogenic microbes (e.g., lactobacillus); antimicrobial proteins or peptides such as those described in U.S. Pat. No. 6,716,813 (Lin et al.) which is expressly incorporated herein by reference or antimicrobial metals (e.g., colloidal silver). 
     Additionally or alternatively, in some applications where it is desired to treat or prevent inflammation the substances delivered in this invention may include various steroids or other anti-inflammatory agents (e.g., nonsteroidal anti-inflammatory agents or NSAIDS), analgesic agents or antipyretic agents. For example, corticosteroids that have previously administered by intranasal administration may be used, such as beclomethasone (Vancenase® or Beconase®), flunisolide (Nasalide®), fluticasone proprionate (Flonase®), triamcinolone acetonide (Nasacort®), budesonide (Rhinocort Aqua®), loterednol etabonate (Locort) and mometasone (Nasonex®). Other salt forms of the aforementioned corticosteroids may also be used. Also, other non-limiting examples of steroids that may be useable in the present invention include but are not limited to aclometasone, desonide, hydrocortisone, betamethasone, clocortolone, desoximetasone, fluocinolone, flurandrenolide, mometasone, prednicarbate; amcinonide, desoximetasone, diflorasone, fluocinolone, fluocinonide, halcinonide, clobetasol, augmented betamethasone, diflorasone, halobetasol, prednisone, dexamethasone and methylprednisolone. Other anti-inflammatory, analgesic or antipyretic agents that may be used include the nonselective COX inhibitors (e.g., salicylic acid derivatives, aspirin, sodium salicylate, choline magnesium trisalicylate, salsalate, diflunisal, sulfasalazine and olsalazine; para-aminophenol derivatives such as acetaminophen; indole and indene acetic acids such as indomethacin and sulindac; heteroaryl acetic acids such as tolmetin, dicofenac and ketorolac; arylpropionic acids such as ibuprofen, naproxen, flurbiprofen, ketoprofen, fenoprofen and oxaprozin; anthranilic acids (fenamates) such as mefenamic acid and meloxicam; enolic acids such as the oxicams (piroxicam, meloxicam) and alkanones such as nabumetone) and Selective COX-2 Inhibitors (e.g., diaryl-substituted furanones such as rofecoxib; diaryl-substituted pyrazoles such as celecoxib; indole acetic acids such as etodolac and sulfonanilides such as nimesulide) 
     Additionally or alternatively, in some applications, such as those where it is desired to treat or prevent an allergic or immune response and/or cellular proliferation, the substances delivered in this invention may include a) various cytokine inhibitors such as humanized anti-cytokine antibodies, anti-cytokine receptor antibodies, recombinant (new cell resulting from genetic recombination) antagonists, or soluble receptors; b) various leucotriene modifiers such as zafirlukast, montelukast and zileuton; c) immunoglobulin E (IgE) inhibitors such as Omalizumab (an anti-IgE monoclonal antibody formerly called rhu Mab-E25) and secretory leukocyte protease inhibitor) and d) SYK Kinase inhibitors such as an agent designated as “R-112” manufactured by Rigel Pharmaceuticals, Inc, or South San Francisco, Calif. 
     Additionally or alternatively, in some applications, such as those where it is desired to shrink mucosal tissue, cause decongestion or effect hemostasis, the substances delivered in this invention may include various vasoconstrictors for decongestant and or hemostatic purposes including but not limited to pseudoephedrine, xylometazoline, oxymetazoline, phenylephrine, epinephrine, etc. 
     Additionally or alternatively, in some applications, such as those where it is desired to facilitate the flow of mucous, the substances delivered in this invention may include various mucolytics or other agents that modify the viscosity or consistency of mucous or mucoid secretions, including but not limited to acetylcysteine (Mucomyst™, Mucosil™) and guaifenesin. 
     In one particular embodiment, the substance delivered by this invention comprises a combination of an anti-inflammatory agent (e.g. a steroid or an NSAID) and a mucolytic agent. 
     Additionally or alternatively, in some applications such as those where it is desired to prevent or deter histamine release, the substances delivered in this invention may include various mast cell stabilizers or drugs which prevent the release of histamine such as cromolyn (e.g., Nasal Chrom®) and nedocromil. 
     Additionally or alternatively, in some applications such as those where it is desired to prevent or inhibit the effect of histamine, the substances delivered in this invention may include various antihistamines such as azelastine (e.g., Astylin®), diphenhydramine, loratidine, etc. 
     Additionally or alternatively, in some embodiments such as those where it is desired to dissolve, degrade, cut, break or remodel bone or cartilage, the substances delivered in this invention may include substances that weaken or modify bone and/or cartilage to facilitate other procedures of this invention wherein bone or cartilage is remodeled, reshaped, broken or removed. One example of such an agent would be a calcium chelator such as EDTA that could be injected or delivered in a substance delivery implant next to a region of bone that is to be remodeled or modified. Another example would be a preparation consisting of or containing bone degrading cells such as osteoclasts. Other examples would include various enzymes of material that may soften or break down components of bone or cartilage such as collagenase (CGN), trypsin, trypsin/EDTA, hyaluronidase, and tosyllysylchloromethane (TLCM). 
     Additionally or alternatively, in some applications, the substances delivered in this invention may include other classes of substances that are used to treat rhinitis, nasal polyps, nasal inflammation, and other disorders of the ear, nose and throat including but not limited to anti-cholinergic agents that tend to dry up nasal secretions such as ipratropium (Atrovent Nasal®), as well as other agents not listed here. 
     Additionally or alternatively, in some applications such as those where it is desired to draw fluid from polyps or edematous tissue, the substances delivered in this invention may include locally or topically acting diuretics such as furosemide and/or hyperosmolar agents such as sodium chloride gel or other salt preparations that draw water from tissue or substances that directly or indirectly change the osmolar content of the mucous to cause more water to exit the tissue to shrink the polyps directly at their site. 
     Additionally or alternatively, in some applications such as those wherein it is desired to treat a tumor or cancerous lesion, the substances delivered in this invention may include antitumor agents (e.g., cancer chemotherapeutic agents, biological response modifiers, vascularization inhibitors, hormone receptor blockers, cryotherapeutic agents or other agents that destroy or inhibit neoplasia or tumorigenesis) such as; alkylating agents or other agents which directly kill cancer cells by attacking their DNA (e.g., cyclophosphamide, isophosphamide), nitrosoureas or other agents which kill cancer cells by inhibiting changes necessary for cellular DNA repair (e.g., carmustine (BCNU) and lomustine (CCNU)), antimetabolites and other agents that block cancer cell growth by interfering with certain cell functions, usually DNA synthesis (e.g., 6 mercaptopurine and 5-fluorouracil (5FU), antitumor antibiotics and other compounds that act by binding or intercalating DNA and preventing RNA synthesis (e.g., doxorubicin, daunorubicin, epirubicin, idarubicin, mitomycin-C and bleomycin) plant (vinca) alkaloids and other antitumor agents derived from plants (e.g., vincristine and vinblastine), steroid hormones, hormone inhibitors, hormone receptor antagonists and other agents which affect the growth of hormone-responsive cancers (e.g., tamoxifen, herceptin, aromatase inhibitors such as aminoglutethimide and formestane, triazole inhibitors such as letrozole and anastrozole, steroidal inhibitors such as exemestane), antiangiogenic proteins, small molecules, gene therapies and/or other agents that inhibit angiogenesis or vascularization of tumors (e.g., meth-1, meth-2, thalidomide), bevacizumab (Avastin), squalamine, endostatin, angiostatin, Angiozyme, AE-941 (Neovastat), CC-5013 (Revimid), medi-522 (Vitaxin), 2-methoxyestradiol (2ME2, Panzem), carboxyamidotriazole (CAI), combretastatin A4 prodrug (CA4P), SU6668, SU11248, BMS-275291, COL-3, EMD 121974, IMC-1C11, IM862, TNP-470, celecoxib (Celebrex), rofecoxib (Vioxx), interferon alpha, interleukin-12 (IL-12) or any of the compounds identified in Science Vol. 289, Pages 1197-1201 (Aug. 17, 2000) which is expressly incorporated herein by reference, biological response modifiers (e.g., interferon, bacillus calmette-guerin (BCG), monoclonal antibodies, interluken 2, granulocyte colony stimulating factor (GCSF), etc.), PGDF receptor antagonists, herceptin, asparaginase, busulphan, carboplatin, cisplatin, carmustine, chlorambucil, cytarabine, dacarbazine, etoposide, flucarbazine, fluorouracil, gemcitabine, hydroxyurea, ifosphamide, irinotecan, lomustine, meiphalan, mercaptopurine, methotrexate, thioguanine, thiotepa, tomudex, topotecan, treosulfan, vinblastine, vincristine, mitoazitrone, oxaliplatin, procarbazine, streptocin, taxol, taxotere, analogs/congeners and derivatives of such compounds as well as other antitumor agents not listed here. 
     Additionally or alternatively, in some applications such as those where it is desired to grow new cells or to modify existing cells, the substances delivered in this invention may include cells (mucosal cells, fibroblasts, stem cells or genetically engineered cells) as well as genes and gene delivery vehicles like plasmids, adenoviral vectors or naked DNA, mRNA, etc. injected with genes that code for anti-inflammatory substances, etc., and, as mentioned above, osteoclasts that modify or soften bone when so desired, cells that participate in or effect mucogenesis or ciliagenesis, etc. 
     Additionally or alternatively to being combined with a device and/or a substance releasing modality, it may be ideal to position the device in a specific location upstream in the mucous flow path (i.e. frontal sinus or ethmoid cells). This could allow the deposition of fewer drug releasing devices, and permit the “bathing” of all the downstream tissues with the desired drug. This utilization of mucous as a carrier for the drug may be ideal, especially since the concentrations for the drug may be highest in regions where the mucous is retained; whereas non-diseased regions with good mucous flow will be less affected by the drug. This could be particularly useful in chronic sinusitis, or tumors where bringing the concentration of drug higher at those specific sites may have greater therapeutic benefit. In all such cases, local delivery will permit these drugs to have much less systemic impact. Further, it may be ideal to configure the composition of the drug or delivery system such that it maintains a loose affinity to the mucous permitting it to distribute evenly in the flow. Also, in some applications, rather than a drug, a solute such as a salt or other mucous soluble material may be positioned at a location whereby mucous will contact the substance and a quantity of the substance will become dissolved in the mucous thereby changing some property (e.g., pH, osmolarity, etc) of the mucous. In some cases, this technique may be used to render the mucous hyperosmolar so that the flowing mucous will draw water and/or other fluid from polyps, edematous mucosal tissue, etc., thereby providing a drying or desiccating therapeutic effect. 
     Additionally or alternatively to substances directed towards local delivery to affect changes within the sinus cavity, the nasal cavities provide unique access to the olfactory system and thus the brain. Any of the devices and methods described herein may also be used to deliver substances to the brain or alter the functioning of the olfactory system. Such examples include, the delivery of energy or the deposition of devices and/or substances and/or substance delivering implant(s) to occlude or alter olfactory perception, to suppress appetite or otherwise treat obesity, epilepsy (e.g., barbiturates such as phenobarbital or mephoobarbital; iminostilbenes such as carbamazepine and oxcarbazepine; succinimides such as ethylsuximide; valproic acid; benzodiazepines such as clonazepam, clorazepate, diazepam and lorazepam, gabapentin, lamotrigine, acetazolamide, felbamate, levetiraceam, tiagabine, topiramate, zonisamide, etc.), personality or mental disorders (e.g., antidepressants, antianxiety agents, antipsychotics, etc.), chronic pain, Parkinson&#39;s disease (e.g., dopamine receptor agonists such as bromocriptine, pergolide, ropinitrol and pramipexole; dopamine precursors such as levodopa; COMT inhibitors such as tolcapone and entacapone; selegiline; muscarinic receptor antagonists such as trihexyphenidyl, benztropine and diphenhydramine) and Alzheimer&#39;s disease, Huntington&#39;s disease or other dementias, disorders of cognition or chronic degenerative diseases (e.g. tacrine, donepezil, rivastigmine, galantamine, fluoxetine, carbamazepine, clozapine, clonazepam and proteins or genetic therapies that inhibit the formation of beta-amyloid plaques), etc. 
     The working element need not necessarily be a substance delivery reservoir  3322 . For example, another type of working element useable in this invention is a laser device. In one embodiment, the laser device may comprise an optical fiber that delivers laser energy through the distal region of the optical fiber. Typical examples of lasers that can be used in the present invention are Nd:YAG lasers, Ho:NAG lasers, short pulsed laser systems such as excimer lasers (wavelength: 308 nm, pulse length full width at half maximum height: 60 ns), dye lasers (wavelength: 504 nm, pulse length full width at half maximum height: 1200 ns), tunable die lasers, KTP lasers, argon lasers, Alexandrite lasers (wavelength: 755 nm, pulse length full width at half maximum height: 300-500 ns) etc. Such a laser device may also be used in conjunction with or as a part of any method, system or device disclosed in this patent application for laser-assisted ablation or cutting, laser-assisted cauterization or other laser-assisted methods of treating sinusitis, mucocysts, tumors, polyps, occlusions, obstructions, edema or other conditions of the paranasal sinuses, Eustachian tubes, Lachrymal ducts, salivary glands and other hard or soft ear, nose, throat or mouth structures. 
     Such devices, systems and methods may also be used for performing other diagnostic or therapeutic procedures of Eustachian tubes, tympanums and middle ear structures. Examples of such procedures are biopsies, microendoscopy of the Eustachian tube and the middle ear structures, diagnosis and/or treatment of roundwindow ruptures, auditory-ossicle dislocations after tympanoplasty, prothesis dislocation after stapeclotomy, neuroradiologically undetectable liquorrhea caused by otobasal fractures, progressive disorders of the sound-conducting apparatus, Dysplasia of the ear, chronic otitis media mesotympanalis, cholesteatoma, presurgical evaluation of pathologic findings of both the mucosal lining and the ossicular chain, epitympanic retraction pockets of the ear drum, all chronic and recurrent ventilation or drainage disorders of Eustachian tubes etc. 
       FIG. 35  shows a perspective view of an embodiment of a guidewire comprising a sensor used for surgical navigation. Guidewire  3400  comprises a sensor  3402  located on the distal region of guidewire  3400 . Sensor  3402  enables guidewire  3400  to be used in conjunction with a suitable surgical navigation system. In one embodiment, sensor  3402  is an electromagnetic sensor used in conjunction with an electromagnetic surgical navigation system such as GE InstaTrak™ 3500 plus system. In one embodiment, guidewire  3400  comprises an anchoring balloon  3404  located on the distal region of guidewire  3400 . Anchoring balloon  3404  is inflated after positioning guidewire  3400  at a target location. Anchoring balloon  3404  anchors guidewire  3400  to adjacent anatomy and prevents accidental repositioning of guidewire  3400  during a diagnostic or therapeutic procedure. Anchoring balloon  3404  may be made from suitable compliant or semi-compliant material such as crosslinked polyethylene or other polyolefins, polyurethane, flexible polyvinylchloride, Nylon etc. In one embodiment, guidewire  3400  comprises a soft distal tip. In another embodiment, guidewire  3400  comprises a curved distal end e.g. a “J” shaped distal end. Sensors similar to sensor  3402  may be present on other diagnostic or therapeutic devices disclosed herein such as balloon catheters etc. Similarly, the devices disclosed herein may comprise other types of sensors or transmitters such as electromagnetic, RF, piezoelectric, magnetic etc. The sensors or transmitters may be in the form of a variety of configurations including but not limited to single coils, multiple coils, antennae etc. The sensors or transmitters may be oriented in a variety of configurations including but not limited to nested, paired, orthogonal to each other, etc. 
       FIG. 35A  shows an enlarged view of an embodiment of a low profile proximal region of the guidewire in  FIG. 35 . The proximal region of guidewire  3400  comprises a distal electrical contact  3406  and a proximal electrical contact  3408 . Distal electrical contact  3406  and proximal electrical contact  3408  are connected to sensor  3402  by conducting wires that run along guidewire  3400  to provide electrical energy to sensor  3402 . Distal electrical contact  3406  and proximal electrical contact  3408  are connected to an external electrical supply by detachable electrodes. Distal electrical contact  3406  and proximal electrical contact  3408  can be made of suitable conducting materials such as stainless steel, silver-palladium alloys, silver-platinum alloys etc. Distal electrical contact  3406  and proximal electrical contact  3408  are separated from each other by a first insulating element  3410 . In one embodiment, guidewire  3400  further comprises a second insulating element  3412  located on the proximal end of guidewire  3400 . A low profile proximal region allows for the introduction of diagnostic or therapeutic devices over guidewire  3400 . 
       FIG. 35B  shows a perspective view of a method of advancing a diagnostic or therapeutic device over the guidewire in  FIG. 35 . In this example, the diagnostic or therapeutic device is a balloon catheter  3414  comprising a shaft  3416  having a balloon  3418  at the distal region of shaft  3416  and a hub  3420  at the proximal end of shaft  3416 . Balloon catheter is advanced into a target anatomical region over the guidewire  3400 . In this example, guidewire  3400  comprises a low profile proximal end so that devices can be introduced in an over-the-wire manner into a target anatomy. 
       FIG. 35C  shows a perspective view of an embodiment of a combination of a guidewire comprising a sensor having a diagnostic or therapeutic device preloaded on the guidewire. In this example, the diagnostic or therapeutic device is balloon catheter  3414 . The proximal end of guidewire  3400  is connected to an external electrical supply  3422  by conducting wires  3424 . In this example, guidewire  3400  does not have a low profile proximal end so that devices cannot be introduced in an over-the-wire manner into a target anatomy. Thus, balloon catheter  3414  is preloaded on guidewire  3400  by inserting proximal end of balloon catheter  3414  over distal end of guidewire  3400 . 
       FIG. 35D  shows a perspective view of a second embodiment of a combination of a guidewire comprising a sensor having a diagnostic or therapeutic device preloaded on the guidewire. In this example, the diagnostic or therapeutic device is balloon catheter  3414 . The proximal end of guidewire  3400  is connected by conducting wires  3426  to plug  3428 . Plug  3428  detachably fits into an external power supply  3430 . In this example, guidewire  3400  does not have a low profile proximal end so that devices cannot be introduced in an over-the-wire manner into a target anatomy. Thus, balloon catheter  3414  is preloaded on guidewire  3400  by inserting proximal end of balloon catheter  3414  over distal end of guidewire  3400 . 
     One or more flexible regions especially flexible distal regions on the diagnostic or therapeutic devices disclosed herein may comprise bending or deflecting elements. Examples of such bending or deflecting elements are one or more pull wires etc. made of suitable materials such as stainless steel flat wire etc. 
     The abovementioned devices and methods may also be used for diagnosing or treating other conditions caused by narrowing or blockage of structures in the ear, nose, throat or mouth such as choanal atresia. 
     Various devices described herein such as catheters may comprise one or more lumens such as end-to-end lumens, zipper lumens, rapid exchange lumens, parallel lumen surrounded by a jacket etc. 
     It is to be appreciated that the invention has been described hereabove with reference to certain examples or embodiments of the invention but that various additions, deletions, alterations and modifications may be made to those examples and embodiments without departing from the intended spirit and scope of the invention. For example, any element or attribute of one embodiment or example may be incorporated into or used with another embodiment or example, unless to do so would render the embodiment or example unsuitable for its intended use. All reasonable additions, deletions, modifications and alterations are to be considered equivalents of the described examples and embodiments and are to be included within the scope of the following claims.