Abstract:
Light energy is utilized to shrink or tighten tissue surrounding a hollow organ, cavity, duct or naturally occurring or surgically created passage by cross-linking the collagen of the surrounding tissue and ccausing scar formation therein. The present device may be used in the esophagus in the area of the sphincter to treat GERD, in the female urethra to treat FSI or at the vesicouretal junction to treat VUR.  
     In the present device, a plurality of plastic tubes, each containing a slidable optical fiber with a sharpened distal end, are affixed to the outer surface of a balloon, which is mounted near the distal end of a closed end catheter. The balloon catheter may be inserted into the body inside a retractable protective sheath. When the sheath is retracted, exposing the balloon, the balloon is inflated, which presses the distal ends of the plastic tubes against the surrounding tissue. The optical fibers are simultaneously advanced manually a selected distance out of the plastic tubes into the tissue surrounding the organ, cavity, duct or passage, reducing the diameter thereof.  
     In a preferred embodiment, superelastic metal tubes with sharp, syringe-shaped ends, which have been preformed into a curved shape, are attached to the distal ends of the optical fibers. When advanced and released from the confines of the plastic tubes, the metal tubes revert to their original shape and curve outward, piercing the tissue. A fluid pathway is provided for injecting a bulking material, such as a biocompatible collagen, to further reduce the diameter of the passageway. The injected collagen can be cross-linked by laser energy, thereby reducing the mobility of the injected bulking material.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to devices and methods for shrinking collagen in body tissue.  
         BACKGROUND OF THE INVENTION  
         [0002]    Gastro esophageal reflux disease or “GERD”, female stress incontinence or “FSI” and vesicouretal reflux or “VUR” affect millions of people in the United States and many more overseas. Pharmaceuticals, such as omeprazole, marketed as Prilosec® by AstraMerck of Wayne, Pa., or rabeprazole sodium, marketed as Aciphex® by Esai Co. of Titusville, N.J. are able to palliate but not cure GERD and usually must be taken for the rest of the person&#39;s lifetime. Surgical treatment of GERD, a procedure called Nissen Fundoplication, is highly invasive, requires general anesthesia, a costly hospital stay and extensive recuperation and creates significant adverse effects, including infections and persistent pain. Likewise, surgical treatments for FSI, including slings, staples, screws and other devices, as well as the injection of collagen, such as manufactured by the Collagen Corporation and distributed as Contigen® by C.R. Bard, Inc. of Murray Hill, N.J., are invasive, entail substantial cost and frequently do not provide lasting relief.  
           [0003]    It would be desirable to be able to treat GERD, VUR, FSI and other conditions in a minimally invasive, non-surgical procedure that could be rendered in a few minutes in a hospital outpatient department or outpatient surgical center, as well as in a physician&#39;s office, without general anesthesia, at modest cost and with little recuperation time.  
         SUMMARY OF THE INVENTION  
         [0004]    Collagen present in tissue surrounding a hollow organ, body cavity, duct or naturally occurring or surgically created passage can be treated with a device embodying the present invention to tighten the tissue around the hollow organ, cavity, duct or passage, such as the esophagus in the area of the sphincter or the female urethra near the bladder neck, so as to alleviate conditions such as gastro-esophageal reflux disease, female stress incontinence, vesico-uretal reflux, and the like. A balloon made of a biocompatible, flexible (non-compliant) or elastic (compliant) material is joined to the distal end of a flexible catheter provided with a rounded, atraumatic, closed distal end. The proximal end of the catheter is provided with a handpiece for manipulating the catheter. One or more ports in the catheter, and within the balloon, provide fluid communication from the catheter into the balloon. A fluid inflow tube joined to the catheter in or near the distal end of the handpiece, provides a passageway for a fluid to be infused through the fluid inflow tube into the catheter to inflate the balloon. An optional vent valve in or near the distal end of the handpiece, permits air to escape when fluid is infused into the catheter to inflate the balloon.  
           [0005]    A plurality of small, flexible tubes are situated on the exterior of the balloon. The tubes terminate preferably at about the balloon&#39;s largest outside diameter when expanded. The proximal ends of the tubes pass through the wall of the catheter and open into its inner lumen, creating a channel for fluid flow therethrough. The openings in the catheter through which the tubes extend are sealed with an adhesive or thermal bonding. The distal end portions of the tubes are free, i.e., not attached to the external surface of the balloon.  
           [0006]    An optical fiber is slidably disposed within each of the tubes. The distal ends of the optical fibers can be beveled or sharpened if desired to facilitate penetration into tissue. The optical fibers extending from the proximal ends of the tubes are joined into a bundle within the catheter by enclosing the same in a casing, for example, made of a heat shrinkable film, or in a sleeve made of a flexible plastic material, as known in the art. The bundle of optical fibers extends through the handpiece, and can be connected to a source of high intensity light or coherent light such as a laser.  
           [0007]    A slidable control button, which may be engaged by the operator&#39;s thumb, is disposed within a slide channel on the exterior of the handpiece. The portion of the button which extends through the slide is attached to a metal sleeve which, in turn, is attached to and surrounds the bundle of optical fibers. When the button is advanced a predetermined distance, an audible “click” is created by a ratchet mechanism, and the optical fibers are extended a like distance out of the distal ends of the tubes in which they are disposed.  
           [0008]    The above described device is slidably disposed within a flexible, retractable, protective sheath, which has markings at predetermined intervals from its distal end. The catheter itself also has markings at the same intervals beginning at the proximal end of the sheath. In use, the catheter/balloon/tube assembly, contained within the sheath, may be inserted into a hollow organ, duct, cavity or passage to a selected position, which has been earlier determined in any convenient manner.  
           [0009]    When placed, the protective sheath is retracted a distance sufficient to expose all or a desired portion of the balloon. A biocompatible fluid is then infused to inflate the balloon, which urges the distal ends of the tubes up against the inner surface of the hollow organ, cavity, duct or passage to be treated. Since the distal end portions of the tubes are not affixed to the balloon, they extend away from the balloon at a greater angle than if they were fully affixed to the balloon.  
           [0010]    The optical fibers are introduced into the tissue a desired distance by the operator&#39;s thumb advancing the control button a like distance. For example, in the treatment of GERD or FSI, the device would be positioned in the esophagus at or near the level of the sphincter or in the female urethra proximal to the bladder neck, respectively. To avoid thermal damage to the sensitive inner lining (mucosa) of the esophagus or urethra, light energy is not transmitted through the optical fibers until they have been inserted through the mucosa into the tissue. Light energy is then emitted for a time sufficient to shrink the tissue, causing mechanical cross linkage of collagen and internal scarring of the tissue. The result of this treatment a is tightening of the muscle tissue surrounding the sphincter or the urethra.  
           [0011]    When light energy of a desired wavelength has been emitted at a desired level and for a sufficient amount of time, the fibers are retracted, the balloon is deflated, the protective sheath is advanced over the catheter/balloon/tube assemblage and the device is removed. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    In the drawings, FIG. 1( a ) is a schematic of the system and an enlarged, cross sectional side view of the handpiece/catheter/balloon/tube assembly of the device of the present invention, with the balloon deflated and without the protective sheath.  
         [0013]    [0013]FIG. 1( b ) is an external view of the distal end portion of the device of the present invention, which has been positioned in the esophagus in the area of the sphincter above the stomach, with the protective sheath in place.  
         [0014]    [0014]FIG. 1( c ) is an external view of the device of FIG. 1( b ) with the protective sheath retracted.  
         [0015]    [0015]FIG. 1( d ) is an external view of the device of FIG. 1( c ) with the balloon inflated and the optical fibers extended into the tissue surrounding the esophagus.  
         [0016]    [0016]FIG. 2 is a cross sectional end view of the optical fiber bundle which extends from a source of light energy.  
         [0017]    [0017]FIG. 3 is a cross sectional, end view of the catheter/balloon/tube/fiber assembly with the balloon deflated.  
         [0018]    [0018]FIG. 4 is a cross sectional, end view of the assembly of FIG. 3 with the balloon inflated.  
         [0019]    [0019]FIG. 5 is a partial, expanded, cross-sectional, side view of the preferred embodiment of the catheter/balloon/tube/fiber assembly with the balloon inflated.  
         [0020]    [0020]FIG. 6 is a partial, expanded, cross sectional, side view of a less preferred embodiment of the assembly of FIG. 5, in which the distal ends of the tubes are fully affixed to the balloon.  
         [0021]    [0021]FIG. 7 is an external top view of an alternative embodiment of the handpiece of the device of FIG. 1.  
         [0022]    [0022]FIG. 8( a ) is an external, top view of an alternate embodiment of the handpiece of the device of FIG. 1.  
         [0023]    [0023]FIG. 8( b ) is a partial, cross sectional top view of the handpiece of FIG. 8( a ) with ratchet mechanism visible.  
         [0024]    [0024]FIG. 9 is a partial, expanded, cross sectional side view of the inflated balloon of the device of FIG. 1, with the tubes and optical fibers manually articulated away from the balloon surface.  
         [0025]    [0025]FIG. 10 is a partial, expanded cross sectional side view of the balloon/tube/fiber/wire assembly of an alternative embodiment of the device of FIG. 1.  
         [0026]    [0026]FIG. 11( a ) is a partial, cross-sectional view of the distal end of an alternate embodiment of the device of the present invention.  
         [0027]    [0027]FIG. 11( b ) is a partial, external view of a component of the device of FIG. 11( a ). 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0028]    While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will be described herein in detail specific embodiments thereof, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not to be limited to the specific embodiments illustrated.  
         [0029]    As shown in FIG. 1( a ), a source of light energy  1 , such as a laser or high intensity light source, is optically coupled to a plurality of optical fibers formed into a bundle  2  by encasing the optical fibers within a flexible plastic casing  3 , such as a heat shrinkable film made, for example, of a fluorocarbon such as polytetrafluoroethylene, or a plastic tube made, for example, of polyethylene, polypropylene, polyurethane or like materials. Proper optical alignment is effected by attaching the connector  4  of bundle  2  to the optical coupler  5  of light source  1 .  
         [0030]    Optical fiber bundle  2  extends through channel  6  in handpiece  7  and is moveable therein. Control button  8  is moveably disposed within slide  9  in handpiece  7 , and may be extended and retracted by thumb pressure of the operator (not shown). Control button  8  extends through slide  9  and is attached to metal sleeve  10 , which is affixed to the exterior of fiber bundle  2  by an adhesive or similar expedient. A ratchet mechanism that emits an audible “click” each time control button  8  is advanced a given distance, for example, one millimeter, can be provided, if desired.  
         [0031]    The proximal end of flexible catheter  11  is attached to the distal end of handpiece  7  in any convenient manner. The distal end  12  of catheter  11  is closed and formed into an atraumatic shape, e.g., a rounded or blunt shape.  
         [0032]    A balloon  13 , which may be made of a flexible, non-compliant plastic film, for example, such as polyurethane or polyethylene, or an elastic, compliant material, for example, such as latex or silicone, is disposed over or about the distal end portion of catheter  11 , spaced from its distal end  12 .  
         [0033]    A plurality of plastic tubes  14 , are attached, e.g., by an adhesive, thermal bonding or other means, to the exterior of balloon  13 , at points just proximal to the distal end portions of the tubes, such that the distal end portions of tubes  14  are free (i.e., are not attached to the balloon). The tubes terminate at or just proximal to the mid-line of balloon  13 . The proximal ends  15  of tubes  14  extend through the wall of catheter  11  and terminate within the lumen of catheter  11 . The openings in catheter  11  through which tubes  14  extend are sealed with an adhesive or other fluid tight material  16 . The free distal end portions of tubes  14  are about 2 to about 10 millimeters long, preferably about 4 to about 7 millimeters long.  
         [0034]    Casing  3 , surrounds optical fiber bundle  2 , and terminates within catheter  11 , usually about 5 to 30 millimeters proximal to the proximal ends  15  of tubes  14 . Individual optical fibers  17  extend distally from casing  3  into tubes  14 . When fully retracted by moving control button  8  on handpiece  7  to its rearward most position, the distal ends of optical fibers  17  extend up to but not beyond the distal ends of tubes  14 . When control button  8  is advanced a predetermined distance, optical fibers  17  exit the distal ends of tubes  14  and extend outwardly the same distance. The distal ends of optical fibers  17  can be beveled or ground into a sharp point to facilitate their penetration into tissue. Optical fibers  17  usually are made of quartz or fused silica, and can have a core diameter of about 100 to 600 microns, preferably about 200 to 400 microns.  
         [0035]    Ports  18 ( a ) in the wall of catheter  11 , within the confines of balloon  13 , provide for entry of fluid to inflate balloon  13 . Fluid infusion tube  19  is attached to catheter  11  through port  18 ( b ), e.g., by an adhesive, thermal bonding or other means, in or distal to the distal end of handpiece  7 . Fluid infusion tube  19  terminates in luer lock  21 , which permits a source of liquid, such as distilled water, saline or a biocompatible, radio-opaque liquid, or a gas, such as carbon dioxide or air, to be injected into catheter  11  from a syringe or pump (not shown), which may be removably attached to luer lock  21 . Optionally, a one-way vent valve (not shown), may be incorporated in catheter  11  through fitting  20  to enable air to escape when fluid is infused into catheter  11  to inflate balloon  13 .  
         [0036]    Luer lock  21 , fluid tube  19 , port  18 ( b ), catheter  11  and port  18 ( a ) create a fluid channel to inflate balloon  13 . Since the open, proximal ends  15  of tubes  14  extend into the lumen of catheter  11 , when fluid is injected into catheter  11  to inflate balloon  13 , fluid also passes through the space between the optical fibers  17  and the lumens of tubes  14  and exits the distal ends of tubes  14  to cool the tissue surrounding balloon  13  at the point of penetration of optical fibers  17 .  
         [0037]    After balloon  13  has been inflated, optical fibers  17  may be extended a desired distance, about 2 to 20 mm, preferably about 3 to 15 mm, into the tissue in contact with balloon  13 . When laser or high intensity light energy is transmitted through and emitted from the distal ends of optical fibers  17  into the tissue, shrinkage of collagen and scar formation takes place within the tissue surrounding balloon  13 , tightening the tissue about the lumen of the hollow organ, cavity duct or passage. Unlike wires used to transmit RF or electrical energy, optical fibers are poor conductors of heat. Consequently, heat does not travel backward through the fibers to injure the sensitive mucosa of the organ, cavity, duct or passage. However, some heat may be conducted through the tissue, which could damage the mucosa or their underlying tissue. The emission of fluid from the distal ends of tubes  14  cools the mucosa or inner surface of the organ, cavity, duct or passage, preventing harm from conduction of heat thereto.  
         [0038]    As shown in FIG. 1( b ), the distal end portion of the device of FIG. 1( a ) has been inserted into the esophagus  22  and positioned in the area of the sphincter  23 , above the stomach  24 . Protective sheath  25  is disposed about the distal end portion of catheter  11 , whose distal tip  12  is seen just distal to the distal end of sheath  22 . A flexible plastic or metal rod  26 , whose distal end is secured to the proximal end of protective sheath  25 , extends through the esophagus  22 , the oral cavity (not shown) and outside the patient&#39;s body. Markings  27  on the exterior of the distal end portion of catheter  11  enable the operator to view through an endoscope (not shown) how far sheath  25  has been retracted.  
         [0039]    As seen in FIG. 1( c ), by retracting rod  26 , protective sheath  25  is moved rearwardly, exposing the distal end portion of catheter  11 , balloon  13  and tubes  14 .  
         [0040]    [0040]FIG. 1( d ) illustrates the device of FIG. 1( a ), in which balloon  13  has been inflated, pressing tubes  14  against the inner surface of the esophagus  22  in the area of sphincter  23 , above the stomach  24 , with optical fibers  17  advanced out of tubes  14  into the surrounding tissue. The arrows indicate the direction of emission of laser energy. Balloon  13  may be made of a non-compliant plastic film, such as polyethylene or polyurethane, or an elastic, compliant material such as silicone or latex.  
         [0041]    As shown in FIG. 2, bundle  2  of seven optical fibers  17  is encased in casing  3 , which in this instance is a heat shrinkable film, such as polyethylene terphthalate or polytetrafluoroethylene. Casing  3  may also be a sleeve made of any other flexible plastic material, as known in the art. The number of optical fibers contained in the bundle can vary from 1 to 20, preferably from 1 to 10.  
         [0042]    [0042]FIG. 3 shows a cross section of the catheter/balloon/tube/fiber assembly, proximal to the mid-line of balloon  13 , which is shown deflated. In this embodiment, six tubes  14 , each containing an optical fiber  17 , are evenly spaced about the exterior of balloon  13 . Any number of tubes  14  may be used.  
         [0043]    [0043]FIG. 4 illustrates the device of FIG. 3, with balloon  13  having been inflated by the infusion of fluid through ports  18 ( a ). In this embodiment, the entire distal end portions of tubes  14  are affixed to balloon  13 .  
         [0044]    An alternative embodiment of the device of FIG. 1( a ) is seen in FIG. 5. In this embodiment, the distal end portions of tubes  14  are not affixed to balloon  13  and, when balloon  13  is inflated, tubes  14  extend from balloon  13  at an angle from the axis of catheter  11  greater than tubes  14  shown in FIG. 4, which are entirely affixed to balloon  13 .  
         [0045]    [0045]FIG. 6 illustrates the catheter/balloon/tube assembly of FIG. 1( b ), with balloon  13  deflated, and disposed within movable outer sheath  25 . The distal end of sheath  25  has an atraumatic, rounded, inwardly extending flange  29 . Alternatively, the distal end of sheath  25  may be blunt ended (not shown) or may contain a rounded, outwardly extending flange (not shown). Gasket  30  is attached by an adhesive or other means inside the proximal end of sheath  25 . Gasket  30  creates a friction fit with catheter  11  and centers catheter  11  within sheath  25 . Gasket  30  also prevents sheath  25  from advancing beyond the point at which tubes  14  exit catheter  11 .  
         [0046]    In use, the distance the device is to be inserted into a body is measured by inserting a sound or other instrument, or by imaging, such as x-ray or ultrasound, or under direct vision through an endoscope. Catheter  11 , with sheath  25  fully extended over balloon  13 , is inserted the desired distance into the body, knowing the length of sheath  25  and noting the markings  27  on catheter  11 . When properly positioned, a clamp may be attached to catheter  11  and the patient or the operating table, so the insertion distance is maintained. Knowing the length of balloon  13  (in this example 6 centimeters), sheath  22  may be retracted  6  centimeters by withdrawing flexible rod  26  until the proximal end of sheath  22  reaches the 6th centimeter mark  27  on catheter  11 , fully exposing balloon  13 . Then the balloon inflation, fiber insertion and lasing procedure may commence. When the lasing procedure has been completed, balloon  13  is deflated by removal of fluid, sheath  25  may be advanced by rod  26  to its original position, and catheter  11  and sheath  25  may be simultaneously removed. While rod  26  is shown here as a slender rod or bar, rod  26  may consist of several rods, a carved slat, or a slotted tube (not shown), which extends about 90° to 240° around the exterior of catheter  111 , the slot enabling markings  27  on catheter  11  to be seen.  
         [0047]    As seen in FIG. 7, fiber bundle  62  may be advanced or retracted within handpiece  66  by advancing or withdrawing button  63 , which is attached to fiber bundle  62  by an extension (not shown). Button  63  is disposed within a longitudinal slide (not shown) in handpiece  66 . When button  63  is advanced or withdrawn, a ratchet mechanism (not shown) emits an audible “click”. One audible “click” made by the ratchet mechanism can indicate fiber bundle  62  has been advanced a chosen distance, for example 1 mm. Optionally, a moveable arrow  64  in window  65  on the exterior surface of handpiece  66  can indicate the distance optical fiber bundle  62  has been advanced from the distal ends of the tubes  14  (not shown).  
         [0048]    In another embodiment of the present invention, shown in FIG. 8( a ) and FIG. 8( b ), handpiece  76  contains button  73 , arrow  74  and window  75 , as described in FIG. 7, to advance and withdraw fiber bundle  72 . Handpiece  76  also contains wheel  78 , which is connected to shaft  79  within handpiece  76 , as shown in cross-sectional view in FIG. 8( b ).  
         [0049]    Wheel  78  is fixedly attached to shaft  79 , which extends perpendicular from the axis of wheel  78 , and which is rotatably disposed within the body of handpiece  76 . Flange  80  of wheel  78  has ridges  72  that engage ratchet mechanism  75 , producing an audible click when wheel  78  has been rotated a predetermined amount, for example 5°. Knob  73  is slidably disposed in longitudinal slot  70  of handpiece  76 , and ratchet mechanism  77  functions to emit an audible “click,” as described in FIG. 7. The proximal ends of articulation wires  71 , are attached to shaft  79 . Articulation wires  71  extend through each of tubes  14 , as described in the device of FIG. 5. When knob  78  is rotated, the proximal ends of articulation wires  71  are wound around shaft  79 , retracting wires  71 .  
         [0050]    As shown in FIG. 9, the distal end of articulation wire  81  is attached to the inner surface of the distal end of tube  84 , opposite the side of tube adjoining balloon  83 , by adhesive or other means, as known in the art. Retracting articulation wire  81 , as described in FIG. 8( b ), causes tube  84 , and optical fiber  87  contained therein, to be angled outward from balloon  83 . Optionally, the distal end  89  of optical fiber  87  may be ground into a pointed shape, as shown, to enable optical fiber  87  to more easily penetrate tissue. A beveled or other shape may also be used. Articulation wire  81  may be made of nitinol or stainless steel, preferably with a diameter of about 0.005″ to about 0.010″. In FIG. 9, optical fiber  87  are shown in a position extended from tube  84 . Articulation wires  81  are preferably retracted with optical fibers  87  fully retracted into tubes  84 , e.g., prior to advancement of optical fibers  87  out of the distal ends of tubes  84 .  
         [0051]    As seen in FIG. 10, a partial, expanded view of a preferred embodiment of the present invention is shown. In this embodiment optical fiber  97  is sheathed within inner catheter  90 , which is disposed within tube  94 . The distal end of tube  94  is fully attached to the surface of balloon  93  as described in for the embodiment shown in FIG. 4. A syringe needle  91  is disposed over the distal end portion of optical fiber  97 , and affixed thereto by crimping at two opposite points, for example, 3 and 9 o&#39;clock, creating fluid passageways at 12 and 6 o&#39;clock, as known in the art. Alternatively, the inner surface of syringe needle  91  may contain ridges or furrows, which provide a fluid passageway between the inner surface of syringe needle  91  and the exterior surface of optical fiber  97 . The length of syringe needle  91  is preferably about 0.7 cm to about 6 cm, more preferably about 1 to about 4 cm. The distal end of inner catheter  90  is attached to the proximal end of syringe needle  91  by an adhesive or the like, creating a fluid passageway. Inner catheter  90  may overlap, and be attached by an adhesive or the like to the proximal end of syringe needle  91 , or the proximal end of syringe needle  91  and the distal end of inner catheter  90  can each be shaped into complementary flanges, creating overlap  92  and thus producing a smooth, contiguous exterior surface.  
         [0052]    In this particular embodiment, syringe needle  91  has a curved shape with a radius of curvature sufficient to create an angle of about 20° to about 100°, preferably about 40° to about 80° from the axis of optical fiber  97  when the syringe needle is partially extended a desired distance out from the distal end of tube  94 . Syringe needle  91  is preferably composed of a superelastic shape memory alloy, most preferably a nickel—titanium (nitinol) alloy, such as TINEL™ available from Memry Corporation of Menlo Park, Calif. When confined within tube  94 , the shape of syringe needle  91  conforms to the radius of curvature of the tube. However, when the syringe needle  91  is extended out of the distal end of tube  94 , it resumes its prefabricated curved memory-shape. No external mechanical means is required to effect this change of shape. This property is referred to as shape memory. Syringe needle  91  is aligned within tube  94 , so that when it is extended from its confinement within tube  94 , syringe needle  91  resumes its curved shape and is angled outward from the surface of balloon  83 , and thus penetrates the tissue surrounding the balloon  83 . Optical fiber  87 , may be extended outward from the distal end of syringe needle  91 , if so desired.  
         [0053]    A bulking material, such as a biocompatible collagen, for example Contigen™ distributed by C.R. Bard, Inc. of Murray Hill, N.J., or Zyplast™, an injectable collagen implant material made by Collagen Aesthetics, Inc. of Palo Alto, Calif., may be injected through the fluid passageways described in FIG. 10 into the tissue surrounding the esophagus to further reduce the diameter of the inner surface of the esophagus in the area of the sphincter by expanding the surrounding tissue. When collagen is heated to a temperature above 55° C., the collagen coils unwind into long tendrils. When collagen cools, the tendrils intertwine as they resume their coil forms. Such intertwining or mechanical cross-linking of the collagen reduces its propensity to migrate away from the injection site.  
         [0054]    The collagen may be injected while laser or other thermal energy is being emitted, which heats the collagen and causes the aforementioned mechanical cross-linking of the collagen. Alternatively, the collagen may be injected first, and laser or other thermal energy may then be emitted to mechanically cross-link the collagen to keep it in place. Injection of a bulking material, can also be employed in other tissues as described herein. Thus, both shrinkage of the tissue from emission of laser energy and further reduction of the inner diameter of a duct, cavity, hollow organ or passageway in tissue can be achieved by injecting a bulking agent using the same device and avoiding a separate procedure.  
         [0055]    FIGS.  11 ( a ) and  11 ( b ) depict an alternative embodiment of the present invention. In FIG. 11( a ) the inflatable balloon of the previously described embodiments is replaced by a flexible cage comprising a plurality of flexible wires  103 . Wires  103  are cylindrically disposed within catheter  101 , throughout its whole length. The distal ends of wires  103  are attached to blunt shaped atraumatic cap  102  to form a cage structure. A plurality of tubes  104  are attached at their distal ends to wires  103  by flexible mesh bands  105 . Mesh bands  105  are preferably made of a superelastic shape memory alloy such as nitinol. FIG. 11( b ) shows an expanded view of the attachment point of tube  104  to wire  103 . The whole cage structure may be retracted into or advanced out of catheter  101  as desired. In FIG. 11( a ) the cage is shown advanced out of the distal end of catheter  101 .  
         [0056]    Tubes  104  extend throughout the entire length of catheter  101  and surround optical fibers  107 . Optical fibers  107  are adapted at their proximal ends for connection to a source of laser energy, and may be retracted into or further extended from the ends of tubes  104 , if the operator so desires. Tubes  104  are flexible and may be slidably moved within catheter  101 , independent of the movement of wires  103 . With the cage structure advanced out of the distal end of catheter  101 , as shown, when the proximal ends of wires  103  are held stationary with respect to catheter  101 , advancement of tubes  104  toward the distal end of catheter  101  causes flexible wires  104  to bow outward to form an expanded cage. Flexible mesh bands  105  then cause the distal ends of tubes  103  to point outward, away from the axis of the catheter  101 . Optical fibers  107  may then be extended out of the distal end of tubes  103  into the surrounding tissue. Laser energy or other thermal energy may then be applied to the surrounding tissue as described for the other embodiments.  
         [0057]    In an alternative embodiment, not shown in the FIGURES, each of optical fibers  107  may be enclosed within an inner catheter and may have a short length of syringe needle affixed to their distal ends, as described in FIG. 10. The resulting fluid passageway may be used to inject a bulking material, such as collagen, as described above.  
         [0058]    In another alternate embodiment, not shown, the cage structure comprising wires  103  and attached tubes  104 , in which optical fibers  107  are slidably retained, may be disposed, if desired, within the retractable protective sheath  25  described in FIGS.  1 ( b ),  1 ( c ),  1 ( d ) and  6  herein, to facilitate atraumatic insertion of the wire/tube/fiber assembly into a hollow organ, cavity, duct or passageway.  
         [0059]    Lasers which may be utilized with the above described devices include, without limitation argon, KTP, diode, Nd:YAG, Alexandrite and Holmium:YAG, the latter requiring optical fibers with a low OH content. High intensity white light may also be used.  
         [0060]    At a given position in the esophagus, after the optical fibers have been deployed, an argon, KTP, diode, Nd:YAG, Alexandrite or other laser may be used at an energy level of about 5 to 30 watts for about 5 seconds to 1 minute, after which the device can be repositioned and the procedure repeated until a sufficient shrinkage or tightening of the tissue around the esophagus has occurred. If a Holmium:YAG laser is being used, about 0.2 to 1 joule per pulse of laser energy at a repetition rate of about 3 to 30 hertz may be employed for about 5 seconds to 1 minute. In the female urethra, for example, less energy for a shorter period of time will be sufficient to achieve the desired shrinkage effect, due to the smaller size of the duct and surrounding tissue.  
         [0061]    The above described devices may be made of various elastic, flexible or rigid materials and in various sizes, depending upon the application. For use through the mouth into the esophagus, the outside diameter of sheath  25  of the device of FIG. 1( c ) can be 4 mm to 15 mm in diameter, preferably about 6 to 10 mm. For use in the female urethra, the outside diameter of sheath  25  should be much smaller, preferably about 2 to 6 mm in diameter.  
         [0062]    Numerous variations and modifications of the embodiments described above may be effected without departing from the spirit and scope of the novel features of the invention. It is to be understood that no limitation with respect to the specific apparatus illustrated herein is intended or should be inferred. It is, of course, intended to cover by the appended claims all such modifications as fall within the scope of the claims.