Abstract:
Conventional vasectomy techniques suffer from a number of disadvantages, including, for example, a substantial risk for the development of hematomas and swelling, a potential for spontaneous regeneration and undesired resumption of fertility, a need for a highly skilled surgical professional, as well as a long recovery period, accompanied by severe limitations on post-surgical activity. The invention disclosed herein overcomes the disadvantages and deficiencies of the prior art by providing a rapid, reliable, less invasive male sterilization procedure as well as a vasectomy device and kit for use therewith.

Description:
PRIORITY  
       [0001]    This application claims the benefit of U.S. Provisional Application Nos. 60/856,304 and 60/906,444, filed Nov. 3, 2006 and Mar. 12, 2007, respectively, the contents of which are hereby incorporated by reference in their entirety. 
     
    
     TECHNICAL FIELD OF THE INVENTION  
       [0002]    The present invention relates to a surgical instrument, and more particularly to a surgical instrument and kit for performing vasectomies and a method for performing vasectomies using the instrument and kit. 
       BACKGROUND OF THE INVENTION  
       [0003]    A vasectomy is surgical procedure which typically involves the removal of all or part of the ducts that carry sperm out of the testes (i.e., the vas deferens), thereby stopping the flow of sperm from the testicle to the prostate gland. After the vas deferens is interrupted, the sperm cannot be delivered and the man is rendered sterile. Unfortunately there are a few complications that are related to the procedure which cause significant concern but no real damage. 
         [0004]    In non-elastic tissue, a small amount of bleeding is quickly stopped by the tension that develops in the tissue. However, the scrotal skin is highly elastic. Accordingly, a tamponade effect is created in most tissue that does not occur in the scrotum. Thus, even the slightest amount of persistent bleeding can cause tremendously large hematomas. Rough handling of the tissue, in a similar manner, causes significant swelling. Even the most experienced vasectomy surgeons occasionally encounter these problems. 
         [0005]    Another problem associated with conventional vasectomy procedures involves the natural tendency of the cut ends of the vas deferens to grow back together, thereby allowing the flow of sperm to the prostate and resumption of fertility. Means for avoiding this failure has been the subject of debate among those skilled in the art, the question being whether the vas deferens should be clipped, cut, cauterized, ligated or all of the above. At present, the prevailing opinion for improving current procedures (discussed hereinafter) seems to be that further dissection (with the potential for further bleeding and swelling) should be used to remove a significant amount of tissue between the cut ends to minimize the possibility of contact. 
         [0006]    Conventional vasectomy procedures are depicted in  FIGS. 1 through 7  and discussed in detail hereinafter. As shown in the Figures, the vas deferens  2  is readily located within the scrotum  4 , between testicles  6  and the prostate. As depicted in  FIG. 1 , a portion of the vas deferens  2  is trapped against the skin of the scrotum  4  by digital manipulation. As seen in  FIG. 2 , a standard blunt-tipped surgical clamp  8  (commonly referred to as a “vas clamp”) is then used to temporarily hold the trapped duct  2  against the skin of the scrotum  4 . The scrotum  4  is then punctured and the wound expanded sufficiently to allow dissection of the vas deferens  2 , following which the duct  2  is grasped at partial thickness using a clamp  10  and extracted as shown in  FIGS. 3 and 4 . As seen in  FIG. 5 , the vas sheath  12  is retracted and an electrocautery with a blunt wire  14  is inserted into each hemitransected vas. In  FIG. 6 , ligation is complete.  FIG. 7  depicts the anatomy after completion of the procedure on a vas deferens. For simplicity purposes, the above discussion describes only the principle steps, shown to demonstrate the principles of the procedure; intermediate steps have been eliminated. In any event, the large number of discrete steps creates multiple opportunities for complications. Also, the presence of bodily fluids during resection steps creates hazardous conditions for clinicians when performing the procedure on an HIV+patient. 
         [0007]    Thus, conventional vasectomy techniques suffer from a number of disadvantages, including, but not limited to, a substantial risk for the development of hematomas and swelling, a potential for spontaneous regeneration and undesired resumption of fertility, a need for a highly skilled surgical professional, as well as a long recovery period, accompanied by severe limitations on post-surgical activity. The present invention is intended to overcome disadvantages and deficiencies of the prior art. 
       SUMMARY OF THE PRESENT INVENTION  
       [0008]    Thus, it is an object of the present invention to provide a rapid, reliable, less invasive male sterilization procedure as well as a novel vasectomy device and kit for use therewith. This and other objectives can be accomplished by the invention herein disclosed. However, regarding the specific objectives recited below, it will be understood by those skilled in the art that one or more aspects of this invention can meet certain objectives, while one or more other aspects can meet certain other objectives. Each objective may not apply equally, in all its respects, to every aspect of this invention. As such, the objects herein can be viewed in the alternative with respect to any one aspect of this invention. 
         [0009]    It is an object of the present invention to provide a method for performing vasectomies that utilizes fewer steps than conventional vasectomy methods.  2 / 22   
         [0010]    It is also an object of the present invention to provide a method for performing vasectomies which may be performed more quickly than current techniques. In some instances, both vas deferens may be treated in less than five minutes. 
         [0011]    It is further an object of the present invention to provide a method for performing vasectomies that reduces the likelihood of complications, including for example, the onset of massive hematomas and swelling. 
         [0012]    It is further an object of the present invention to provide a method for performing vasectomies which reduces or eliminates the possibility of spontaneous reconnection of the vas deferens, thereby eliminating an avenue for failure associated with conventional procedures. 
         [0013]    It is further an object of the present invention to provide a method for performing vasectomies that allows patients to immediately resume normal activities, including, for example, showering and bathing. 
         [0014]    It is further an object of the present invention to provide a method for performing vasectomies that allows patients to more quickly resume normal activities of daily living and work, providing a substantially shortened recovery period as compared with conventional vasectomies. 
         [0015]    It is further an object of the present invention to provide a method for performing vasectomies in which there is little or no opportunity for contact with bodily fluids. In this manner, the method permits the performance on HIV+patients and individuals with other blood-borne diseases (e.g., Hepatitis) with minimal risk to the clinician. 
         [0016]    It is further an object of the present invention to provide a surgical instrument for performing vasectomies which allows the vasectomy procedure to be completed using a single instrument and a vas clamp. 
         [0017]    It is further an object of the present invention to provide a surgical instrument for performing vasectomies which allows the vasectomy procedure to be performed by clinicians with limited training. 
         [0018]    It is further an object of the present invention to provide a kit for performing vasectomies containing the novel surgical instruments of the present invention, coupled with other conventional materials that are required to complete the vasectomy procedure. Pursuant to the objectives listed herein, the present invention herein provides 
         [0019]    Pursuant to the objectives listed herein, the present invention herein provides a method for performing a vasectomy, optionally including the steps of: (a) locating the vas deferens within the scrotum; (b) temporarily isolating a length of the vas deferens in a fold of scrotal skin; (c) placing a clamping vasectomy device around a portion of the isolated scrotal skin containing the length of vas deferens, wherein the clamping vasectomy device is configured to retain an arcuate area of clamped scrotal tissue containing a first and second segment of the vas deferens, the clamping vasectomy device having an interior perimeter which defines a convex area of unclamped scrotal tissue that contains a third segment of the vas deferens; and (d) excising some or all of the convex area of unclamped scrotal tissue, including the third segment of vas deferens. 
         [0020]    The clamping step may in one embodiment result in the physical crushing of the clamped scrotal tissue. In an alternate embodiment, the clamping step may result in the thermal coagulation of the clamped tissue. To that end, the present invention provides an alternate embodiment of the method for performing a vasectomy that includes the steps of: (a) locating the vas deferens within the scrotum; (b) temporarily isolating or trapping a length of the vas deferens in a fold of scrotal skin, for example by means of a standard vas clamp; (c) positioning an arcuate clamping vasectomy device around the portion of scrotal skin containing the isolated length of vas deferens, the clamping device being optionally connected to the bipolar output of an electrosurgical generator; (d) applying cauterizing energy, for example radio frequency (RF) power, to the clamped portion of scrotal tissue so as to thermally coagulate the tissue; and (e) excising or removing tissue the unclamped scrotal tissue defined by the curve of the clamping device, the excised tissue containing at least a portion of the vas deferens. 
         [0021]    In either of the above-described embodiments, the step of locating the vas deferens may be accomplished through routine digital manipulation. Likewise, the step of temporarily isolating a length of the vas deferens may be accomplished using a standard vas clamp. 
         [0022]    In either of the above-described embodiments, excision step may be achieved by means of conventional cutters (e.g., surgical scalpels and the like) or through electrosurgical ablation, using, for example a cutting electrode such as a bipolar RF electrode. The former embodiment necessitates a subsequent step of sealing the cut are, by means of surgical adhesive, suture, cauterization or a combination thereof. 
         [0023]    The present invention further provides a vasectomy device for removing a section of the vas deferens trapped within a fold of scrotal skin, more particularly a clamping instrument having a proximal handle portion and a distal clamping portion, the clamping portion having a pair of opposingly faced upper and lower jaws movable between open and closed positions, wherein the jaws in the closed position are configured to retain an arcuate area of clamped tissue, wherein the jaws further include a pair of mating inner edges that engage to form a continuous curved perimeter which in use defines a convex area of unclamped tissue. 
         [0024]    In one embodiment, the vasectomy device of the present invention may optionally further include a means for cauterizing clamped tissue, for example through inclusion of one or more electrodes having one or more output ends positioned on an engaging face of either or both of the upper and lower jaws. 
         [0025]    In another embodiment, the vasectomy of the present invention may optionally further include a cutting electrode configured to slidably engage the continuous curved perimeter defined by the inner edges of the upper and lower jaws. 
         [0026]    In yet another embodiment, the vasectomy of the present invention may optionally further include a power source, for example a radio frequency (RF) generator optionally mounted to the handle portion of the clamping instrument. 
         [0027]    The present invention further provides a kit for performing a vasectomy containing the vasectomy device of the present invention in combination with one or more standard vas clamps. The kit may optionally further contain a local anesthetic and/or a power source, optionally mountable to the vasectomy device and/or composed of one or more rechargeable batteries capable of delivering cauterizing radio frequency energy. 
         [0028]    These and other objects and features of the invention will become more fully apparent when the following detailed description is read in conjunction with the accompanying figures and examples. However, it is to be understood that both the foregoing summary of the invention and the following detailed description are of a preferred embodiment and not restrictive of the invention or other alternate embodiments of the invention. In particular, while the invention is described herein with reference to a number of specific embodiments, it will be appreciated that the description is illustrative of the invention and is not constructed as limiting of the invention. Various modifications and applications may occur to those who are skilled in the art, without departing from the spirit and the scope of the invention, as described by the appended claims. Likewise, other objects, features, benefits and advantages of the present invention will be apparent from this summary and certain embodiments described below, and will be readily apparent to those skilled in the art. Such objects, features, benefits and advantages will be apparent from the above in conjunction with the accompanying examples, data, figures and all reasonable inferences to be drawn therefrom, alone or with consideration of the references incorporated herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0029]    Various aspects and applications of the present invention will become apparent to the skilled artisan upon consideration of the brief description of the figures and the detailed description of the present invention and its preferred embodiments which follows: 
           [0030]      FIG. 1  is a prior art figure that depicts a perspective view of manual location of the vas deferens within the scrotum. 
           [0031]      FIG. 2  is a prior art figure that depicts a perspective view of the vas isolated in a fold of the scrotum using a vas clamp. 
           [0032]      FIG. 3  is a prior art figure that depicts a step in a conventional vasectomy procedure in which the vas deferens is extracted from the scrotum 
           [0033]      FIG. 4  is a prior art figure that depicts a step in a conventional vasectomy procedure in which the vas deferens is dissected. 
           [0034]      FIG. 5  is a prior art figure that depicts a step in a conventional vasectomy procedure in which the sheath has been retracted on the vas duct and electrocautery is used to 
           [0035]      FIG. 6  is a prior art figure that depicts a step in a conventional vasectomy procedure in which ligation is complete. 
           [0036]      FIG. 7  is a prior art figure that depicts the anatomy at the completion of a conventional vasectomy procedure. 
           [0037]      FIG. 8  depicts a portion of the anatomy after a vasectomy operation in accordance with the principles of this invention. 
           [0038]      FIG. 9  depicts a system for performing vasectomies including an instrument constructed in accordance with the principles of this invention. 
           [0039]      FIG. 10(   a ) is an exploded view of a first subassembly of a vasectomy device constructed in accordance with the principles of this invention. 
           [0040]      FIG. 10(   b ) is a plan view of the objects of  FIG. 10(   a ). 
           [0041]      FIG. 10(   c ) is a side elevational view of the objects of  FIG. 10(   a )  FIG. 10(   d ) is a perspective view of the objects of  FIG. 10(   a ). 
           [0042]      FIG. 11(   a ) is an exploded view of a second subassembly of a vasectomy device constructed in accordance with the principles of this invention. 
           [0043]      FIG. 11(   b ) is a plan view of the objects of  FIG. 11(   a ). 
           [0044]      FIG. 11(   c ) is a side elevational view of the objects of  FIG. 11(   a ). 
           [0045]      FIG. 11(   d ) is a perspective view of the objects of  FIG. 11(   a ). 
           [0046]      FIG. 12  is a side elevational view of a vasectomy instrument constructed in accordance with the principles of this invention. 
           [0047]      FIG. 13  is an expanded plan view of the distal portion of the objects of  FIG. 12 . 
           [0048]      FIG. 14  is a perspective view of the device of  FIG. 12  with the clamping jaws opened for use. 
           [0049]      FIG. 15  is a plan view of a clamping instrument formed in accordance with the principles of this invention and suitable for use with the vasectomy device of  FIG. 12 . 
           [0050]      FIG. 16  is a side elevational view of the objects of  FIG. 15 . 
           [0051]      FIG. 17  is a perspective view of the objects of  FIG. 15 . 
           [0052]      FIG. 18  is a plan view of the clamping instrument of  FIG. 15  suitable for use in a vasectomy procedure. 
           [0053]      FIG. 19  is a perspective view of the objects of  FIG. 18 . 
           [0054]      FIG. 20  is a plan view of the clamping instrument of  FIG. 15  suitable for use with the vasectomy device of  FIGS. 12 to 14 . 
           [0055]      FIG. 21  is a perspective view of the objects of  FIG. 20 . 
           [0056]      FIG. 22  is an expanded plan view of the distal portion of the objects of  FIG. 20 . 
           [0057]      FIG. 23  is an expanded perspective view of the objects of  FIG. 22 . 
           [0058]      FIG. 24  is an expanded view of the distal portion of the vasectomy device of  FIGS. 12 to 14  in use with coagulated tissue clamped between the jaws. 
           [0059]      FIG. 25  is a perspective view of the objects of  FIG. 24 . 
           [0060]      FIG. 26  is a side elevational view of the vasectomy device of  FIGS. 12 to 14  at the completion of a vasectomy procedure before the clamping jaw pressure is released. 
           [0061]      FIG. 27  is an expanded side elevational view of the distal portion of the objects of  FIG. 26 . 
           [0062]      FIG. 28  is an expanded perspective view of the objects of  FIG. 27 . 
           [0063]      FIG. 29  depicts the site after completion of a vasectomy procedure in accordance with the principles of this invention. 
           [0064]      FIG. 30  is an expanded perspective view of the distal portion of an alternate embodiment formed in accordance with the principles of this invention. 
           [0065]      FIG. 31  is a plan view of the objects of  FIG. 30 . 
           [0066]      FIG. 32  is an expanded side elevational sectional view of the objects of  FIG. 30  at location A-A of  FIG. 30 . 
           [0067]      FIG. 33  is an expanded perspective view of the distal portion of an alternate embodiment formed in accordance with the principles of this invention. 
           [0068]      FIG. 34  is a plan view of the objects of  FIG. 33 . 
           [0069]      FIG. 35  is an expanded axial sectional view of the objects of  FIG. 33  at location A-A of  FIG. 34 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0070]    It is to be understood that this invention is not limited to the specific devices, systems, methodologies or protocols herein described, as these may vary in accordance with routine experimentation and optimization. It is also to be understood that the terminology used in the description is for the purpose of describing the particular versions or embodiments only, and is not intended to limit the scope of the present invention which will be limited only by the appended claims. It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural reference unless the context clearly dictates otherwise. Thus, for example, reference to a “clamp” is a reference to one or more clamps and equivalents thereof known to those skilled in the art, and so forth. 
         [0071]    All publications mentioned herein are incorporated herein by reference in their entirety. However, nothing herein should be construed as an admission that the invention is not entitled to antedate such disclosure by virtue of prior invention. 
         [0072]    Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. However, in case of conflict, the present specification, including definitions, will control. Accordingly, in the context of the present invention, the following definitions apply: 
         [0073]    As used herein, the noted directional terms relate to a human body in a standing position. For instance, “up” refers to in the direction of the head, “down” refers to in the direction of the feet. Herein, the “vertical” direction is parallel to the axis of the body and the “horizontal” direction is parallel to the floor. “Lateral” refers to the direction extending away from the center of the body whereas “medial” refers to a direction extending toward the center of the body. 
         [0074]    In the context of the present invention, the term “proximal” refers to that end or portion of a device or instrument which is situated closest to the body of the subject when the device is in use. 
         [0075]    In the context of the present invention, the term “distal” refers to that end or portion of a device or instrument which is situated farthest away from the body of the subject when the device is in use. 
         [0076]    In the context of the present invention, the term “arcuate” is used herein to describe shapes forming or resembling an arch. It is used interchangeably with its synonym, arciform. 
         [0077]    In the context of the present invention, the term “convex” refers to a surface or boundary that curves outward, as the exterior of a sphere. Conversely, the term “concave” refers to a surface or boundary that curves inward, as to the inner surface of a sphere, or is hollowed or rounded inward like the inside of a bowl. Herein, the area of unclamped scrotal tissue defined by the U-shaped jaws of the clamping vasectomy device of the instant invention and the arcuate area of clamped scrotal tissue contained therein is referred to as convex in shape. 
         [0078]    As noted above, the present invention is characterized by substantial advantages not found in conventional methods and devices. For example, by avoiding direct dissection and resulting bleeding, the present invention is able to eliminate the risk for development of massive hematomas and swelling. In addition, the present invention allows for the separation of the vas deferens in such a manner that it is virtually impossible for the ends of the vas deferens to contact each other and rejoin. Also, the number of steps in the procedure is much less than for other current vasectomy techniques thereby reducing opportunities for complications. The inherent simplicity of the disclosed procedure and associated instruments simplifies training and allows clinicians with limited experience to master their use. Moreover, the procedures of the present invention avoid exposure to bodily fluids, which, in turn, minimizes risks of transmission of blood-born diseases, such a HIV and Hepatitis, to performing clinicians. 
         [0079]    The present invention is further characterized by surgical instruments designed to perform vasectomies in accordance with the methods herein described. In one preferred embodiment, the instrument has clamping jaws, preferably a pair of opposingly faced upper and lower arcuate or “U” shaped jaws. The jaws may optionally be connected via electrical wiring to the bipolar output of an electrosurgical generator. The clamping jaws, when viewed in a plan view, preferably have a distal arcuate portion subjected to clamping pressure by the jaws, and an approximately semicircular center portion which is not subjected to clamping pressure. The jaws further include a lateral opening (or gap) that allows the clamping jaws to be positioned around a conventional vas clamp which serves to maintain the position of the vas deferens in the fold of scrotal skin. To prevent accidental shorting between the clamping jaws when connection with electrosurgical generator, the vas clamp is preferably formed from a suitable dielectric material, examples of which are readily known in the art. 
         [0080]    In a particular preferred embodiment, the surgical instrument of the present invention is optionally provided with a movable cutting electrode on the distal end of a pivoting arm, such that when deployed the movable electrode intersects tissue within the semicircular center portion of the clamping jaws so as to electrosurgically remove the center portion. The cutting electrode is connected via circuitry within the instrument to the bipolar output of the electrosurgical generator. In a preferred embodiment, both the upper jaw and the cutting electrode are continuously connected to the same bipolar output cable of the generator. In an alternate embodiment, a switching means allows the first bipolar output of the generator to be connected to either the upper clamping jaw or the cutting electrode. 
         [0081]    In use, a segment of the vas deferens is trapped within a fold of scrotal skin and its position is maintained using a standard vas clamp, optionally formed from a suitable dielectric material. The portion of the scrotum having the vas deferens is clamped between the jaws of the instrument, with the vas clamp in the center portion of the jaws. In one preferred embodiment, a ratchet mechanism may be included to maintain the clamping force. Energy can then be applied via the clamping jaws to the tissue trapped therebetween. In one embodiment, the energy may involve simple crushing of the captured tissue, which, in turn results in the formation of an arcuate area of crushed tissue. This tissue, because of the crush, will remain as a “cake” for a brief period of time, during which the tissue held by standard vas clamp. 
         [0082]    In an alternate embodiment, the energy may take the form of thermal energy, preferably in the form of RF power from the electrosurgical generator, the power level being sufficient to thermally coagulate the tissue thereby sealing the ends of the vas deferens, fusing them to the scrotal skin, and fusing the fold in the scrotal skin so as to form a contiguous mass. The length of time for coagulation is determined by the operator, typically through foot pedal activation of the generator. In a preferred embodiment, the electrosurgical unit monitors the impedance of the tissue between the clamped jaws of the instrument and based on changes in the impedance determines when coagulation is complete. In another embodiment, the time duration during which power is supplied to the instrument for coagulation is determined by a timer within the electrosurgical unit. When the tissue is fully coagulated, while the tissue is still clamped between the jaws, the vas clamp is removed. Subsequently, the electrosurgical unit is activated so as to allow the cutting electrode to remove the un-coagulated tissue in the center of the coagulated arcuate portion, after which the cutting electrode returns to its original position. The ratchet can then be released, which, in turn, allows the clamping jaws to be removed from the site. In this embodiment, closure of the wound by suturing or adhesive is not required. Accordingly, the patient may bathe or shower as soon as desired. Although traditional vasectomies recommend minimal activity for 48 hours and limited activities for one week, in the context of the present invention there are no contra-indications to the patient resuming any normal activity that does not involve direct trauma to the scrotum. 
         [0083]    The surgical instrument herein described has components that are preferably formed from injection moldable polymeric materials having molded therein, when required, metallic components that permit connection to electrical circuitry at their proximal end, and either a clamping jaw or a cutting electrode at their distal end. In a preferred embodiment, the instrument takes the form of a single-use disposable product, while in another embodiment, it is constructed for limited reuse. 
         [0084]    The present invention is further characterized by a kit for performing vasectomies, the kit containing the clamping/resecting surgical instrument of the present invention in combination with one or more standard vas clamps, preferably formed from a suitable dielectric material. 
         [0085]    Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, particular aspects and preferred embodiment of the present invention are depicted in the accompanying figures and described hereinafter. However, the embodiments described herein are merely intended to illustrate the principles of the invention. Those skilled in the art will recognize that variations and modifications may be made to the embodiments without changing the principles of the invention herein disclosed. Accordingly, the accompanying figures, described in detail below, that depict aspects of the invention are in no way intended to limit the scope of the present invention. 
         [0086]    Referring now to  FIG. 8 , portion of the anatomy after completion of a vasectomy performed in accordance with the principles of this invention is depicted. Arcuate portion  20  containing first and second segments of the vas deferens  2  and skin of scrotum  4  has been coagulated so as to form a contiguous structure, and center portion  22  of which, containing a third segment of the vas deferens  2  and scrotal skin  4 , has been removed. 
         [0087]      FIG. 9  depicts an illustrative vasectomy device  100  constructed in accordance with the principles of the present invention connected by electrical cable  142  to electrosurgical generator  50 . 
         [0088]      FIGS. 10(   a ) through  10 ( d ) depicts a first subassembly  102  of device  100 . Subassembly  102  has a first member  104  with a proximal end  106  having a vertical portion  108  the top of which has a tapered distal facing portion  110 . Member  104  has a distal end  112  having an upper clamping jaw  114  electrically connected to connector portion  116 . In a preferred embodiment member  104  is injection molded form a suitable polymeric material, and jaw  114  and connector portion  116  are portions of a stamping formed from stainless steel, titanium, nickel, or another suitable conductive or metallic material, the stamping being inserted into the injection mold prior to injection of the polymeric material. Second member  120  has a proximal end  122  having a more or less vertical arcuate protuberance  124  having a diameter less than that of hole  126  in the mid-portion of first member  104 , and less than the internal diameter of spring  134  such that on assembly protuberance  124  is positioned within spring  134 . Distal end  128  of second member  120  has protruding distally therefrom electrode  130  which is electrically connected to connector portion  132 . In a preferred embodiment, the second member  120  is injection molded form a suitable polymeric material, and electrode  130  and connector portion  132  are portions of a stamping formed from stainless steel, titanium, nickel, or another suitable conductive or metallic material, the stamping being inserted into the injection mold prior to injection of the polymeric material. Second member  120  is pivotably positioned within first member  104  by sleeve  136 , spring  134  causing second member  120  to be rotated such that distal end  142  of electrode  130  is displaced angle  140  from line  144 . 
         [0089]      FIGS. 11(   a ) through  11 ( d ) depict a second subassembly  150  of device  100 . Member  152  has a proximal end  154  with mounting holes  156  and locating hole  158 , and a distal end  160  from which protrudes lower clamping jaw  162  which is electrically connected to connector portion  164 . In a preferred embodiment, member  152  is injection molded form a suitable polymeric material, and lower clamping jaw  162  and connector portion  164  are portions of a stamping formed from stainless steel, titanium, nickel, or another suitable conductive or metallic material, the stamping being inserted into the injection mold prior to injection of the polymeric material. Mounting block  168  is mounted to proximal end  154  of member  152  by pins  170 . Lateral surface  172  of block  168  has a plurality of protuberances  174  which form a labyrinth strain relief for an electrical cable placed therein. Upper surface  169  of block  168  has formed thereon cylindrical protrusion  171  which engages locating hole  158  in member  152  when block  168  is mounted to member  150 . Ratchet arm  176  is pivotably mounted in channel  178  of block  168  by pin  180 , spring  182  causing arm  176  to rotate such that proximal stop portion  184  of arm  176  contacts the upper surface of channel  178 . First portion  186  of arm  176  has formed therein spring pocket  188  for containing spring  182 . Second portion  190  of arm  176  has formed in its proximal surface ratchet teeth  192 . Member  152  has formed therein opening  194 . 
         [0090]    Referring now to  FIG. 12  depicting device  100 , subassembly  102  is pivotably assembled to subassembly  150  by pin  200  passing through holes  196  in member  152  and sleeve  136  of subassembly  102  such that member  120  pivots freely within member  104 , and member  104  of subassembly  102  pivots freely within member  152 . Teeth  192  of ratchet arm  176  in cooperation with tapered distal portion  110  of vertical portion  108  of member  102  maintain clamping pressure between lower jaw  162  and upper jaw  114 . Electrical cable  202  connects connector portion  116  connected to upper jaw  114  to cable  204 . Electrical cable  208  connects connector portion  164  connected to lower jaw  162  to cable  204 . Cable  212  connects connector portion  132  connected to electrode  130  to cable  204 . Cables  202 ,  208  and  212  have at their distal terminal ends mating connector portions which together with portions  116 ,  164  and  132  form connector pairs, the connector pairs forming sealed assemblies. 
         [0091]    When viewed in a plan view as in  FIG. 13 , jaws  114  and  162  (hidden beneath jaw  114 ) each have a proximal portion  220  connecting ends  222  of arcuate distal portions  224  to members  104  and  152 , arcuate distal portions  224  having an inner radius  226 , an outer radius  228 , and a radial width  230 . Ends  232  of arcuate portions  224  are displaced distally from members  104  and  152  distance  234  so as to form a gap  236 . Inner radius  226  is preferably between 0.5 and 4 millimeters, and more preferably between 1 and 3 millimeters. Radial width  230  is preferably between 1 and 6 millimeters, and more preferably between 2 and 4 millimeters. Arcuate distal portions  224  define inner regions  238 . Electrode  130  has formed in its distal portion  150  opening  240  so as to form a perimitral ring  241 . 
         [0092]      FIG. 14  depicts device  100  ready for use in performing a vasectomy, jaws  114  and  162  being angularly displaced so as to allow the placement of tissue therebetween for clamping. 
         [0093]    Performing a vasectomy according to the method in accordance with the principles of this invention requires the use of vasectomy device  100 , and a clamping instrument  300 , depicted in  FIGS. 15 through 17 , formed from a suitable dielectric material. In a preferred embodiment instrument  300  is formed from a thermoplastic material by injection molding. In a further preferred embodiment, the injection moldable thermoplastic is a composite material having an inorganic filler material for added rigidity. Clamping instrument  300  has a first member  302  and a second member  304 , members  302  and  304  together forming a clamping assembly rotatably joined by pivot  306 , the assembly having a proximal end  308  forming finger loops  310 , and a distal end  312  forming clamping surfaces  314  having adjacent thereto arched portions  316 . When viewed in a plan view as in  FIG. 16 , distal end  312  is offset from the body of instrument  300  angle  318 . Interlocking portions  320  maintain clamping force on tissue between clamping surfaces  314 , sideways pressure on proximal ends  308  releasing the clamping force. 
         [0094]    A vasectomy procedure performed according to the method of this invention using instruments  100  and  200  begins using the same initial steps as a conventional vasectomy. That is, a vas duct is located and trapped within a fold of scrotal skin as shown in  FIG. 1 , and is retained in the fold using a clamp as shown in  FIG. 2 , except clamp  200  is used as shown in  FIGS. 18 and 19  in which vas duct  2  is retained in a fold of scrotal skin  4  by clamping surfaces  214 . ( FIGS. 16 and 17 ) Arched portions  216  provide clearance for the fold and duct  2 . Subsequently, as shown in  FIGS. 20 through 23 , the fold of scrotal skin  4  and vas duct  2  are positioned between lower jaw  162  and upper jaw  114  of instrument  100  and clamped by the jaws, the clamping pressure being maintained by the ratchet assembly formed by arm  176  and proximal portion  108  of member  104  ( FIG. 12 ). Gap  236  ( FIG. 13 ) between distal arcuate portions  224  of jaws  114  and  162  and members  104  and  152  of device  100  allow distal end  312  of clamp  300  to be positioned such that jaws  114  and  162  can be closed on tissue placed between them without interference from distal portion  312  of clamp  300 . When the jaws are clamped as shown in  FIGS. 22 and 23 , RF energy from the electrosurgical generator is supplied to jaws  114  and  162  causing thermal coagulation of the scrotal skin  4  and the portion of vas duct  2  between jaws  114  and  162  so as to fuse the tissue into a contiguous mass. When coagulation of the tissue is complete, clamp  300  is removed. The coagulated tissue remains clamped between jaws  114  and  162  as shown in  FIGS. 24 and 25 . Tissue in the central region  238  of jaws  114  and  162  is not coagulated. The electrosurgical generator is activated again and member  120  is rotated causing electrode  130  to advance to a position below lower jaw  162  so as to electrosurgically remove the uncoagulated tissue  360  in the central region  238  of jaws  114  and  162 . The generator is then deactivated, member  120  is released allowing electrode  130  to return to its first position. Portion  186  of ratchet arm  176  is depressed releasing teeth  192  from tapered distal facing portion  110  of portion  108  of member  104  releasing the clamping force between jaws  114  and  162 . Instrument  100  is now ready to perform the same procedure on the other vas deferens. 
         [0095]    One skilled in the art will readily recognize that numerous changes may be made to instrument  100  without departing from the principles of this invention. For instance, resection of tissue portion  360  from center portion  129  of jaws  114  and  162  is accomplished by electrode  150 . In other embodiments tissue portion  360  is resected by a conventional (non-electrosurgical) cutting feature.  FIGS. 30 through 32  depict the distal portion of an embodiment in which center tissue portion  360  is removed by a sharpened edge not connected to the electrosurgical generator. Instrument  400  is identical to instrument  100  in all aspects except that electrode  130  of device  100  is replaced by cutting element  430 . Element  430  (not connected to generator  50 ) has at its distal end perimetral ring  541  which has a sharpened lower portion  543  forming a cutting edge. When coagulation of arcuate portion  20  ( FIG. 29 ) is completed by clamping jaws  414  and  462  and clamp  300  has been removed, tissue portion  360  is removed by cutting edge  543 . In another embodiment, the distal portion of which is depicted in  FIGS. 33 through 35 , tissue portion  360  is resected from the center of the arcuate coagulated tissue portion by a cutting edge integral with one of the clamping jaws. A cutting element, either electrosurgical like element  130  of instrument  100 , or conventional like element  430  of instrument  400 , is not required thereby allowing the construction of the instrument to be simplified. Distal end  660  of member  652  has an added distal portion  663  which supports lower jaw  662  and has a portion  665  positioned beneath cutting edge portion  615  of upper jaw  614 . Cooperative interaction between cutting edge  615  of upper jaw  614  and portion  665  of portion  663  cuts tissue placed therebetween, separation of the tissue occurring when jaws  614  and  662  are clamped together. Device  600  is advantageous since removal of tissue portion  360  is accomplished with clamp  300  in place so as to ensure that a portion of vas deferens  2  is removed. In another embodiment, the cutting element (element  130  of device  100 , or element  430  of device  400 ) is configured such that tissue portion  360  can be removed by the element without removal of clamp  300 . 
         [0096]    In yet another embodiment, removal of tissue portion  360  is accomplished by a second instrument, either a conventional cutting device such as, for instance a scalpel, or by an electrosurgical instrument such as, for instance, a standard Bovie knife. 
         [0097]    Generator  50 , when operated in bipolar mode, is activated using a foot-pedal, RF energy being supplied to devices electrically connected to the bipolar output while the foot-pedal is depressed. The time required to achieve a desired clinical effect is determined by the clinician operator. When using instrument  100 , the time required for coagulation is determined by the operator who determines the length of time that his foot depresses the foot-pedal. In a preferred embodiment instrument  100  is part of a system in which generator  50  is a low-cost dedicated generator designed for use only with instrument  100 . Specialized generator  50  of this embodiment is low-cost since it has only one output, a bipolar one, at a fixed power level using a single waveform. Dedicated generator  50  has other advantages, primarily with regard to the coagulating portion of the process. In a preferred embodiment generator  50  has a means for determining the time duration during which RF power is applied to the tissue for coagulation. In a preferred embodiment, the impedance of the tissue between the jaws is monitored. Because the impedance of tissue changes during coagulation, RF power may be applied until a predetermined impedance value is reached, or until a predetermined degree of impedance change is reached. In another embodiment the means is a timer which may be set by the operator or which is preset. 
       INDUSTRIAL APPLICABILITY  
       [0098]    As noted previously herein, the vasectomy device, kit and method for performing vasectomies of the present invention overcome disadvantages and deficiencies of conventional vasectomy materials and methods by providing a rapid, reliable, less invasive male sterilization procedure that reduces or eliminates negative side effects, including swelling and spontaneous regeneration, and minimizes recovery time and recovery restrictions. It further minimizes the potential for exposure to patient bodily fluids, thereby minimizing the potential for transmission of blood-borne diseases such as HIV and Hepatitis. For example, the vasectomy method herein described does not produce bleeding and, aside from the needle used for injection of the local anesthetic, does not require the use of any sharp instruments which could inadvertently penetrate the skin of the operator. Thus, thee procedure may be performed on patients who are, for instance, HIV positive, with minimal risk to the clinician compared to other methods. 
         [0099]    Because of the complications associated with traditional vasectomies but eliminated by the technique and device herein disclosed, successful procedures have, in the past, required the utilization of skilled experienced surgeons. The vasectomy device and method of the instant invention minimizes the number of steps and duration of the procedure, thereby allowing the procedure to be quickly completed by clinicians with minimal training. Moreover, given its simplicity, less skilled heath care workers can master the procedure in relatively short period of time. This will extend the feasibility of male sterilization to areas of the world where doctors, more particularly skilled surgeons, are in short supply. For example, the instruments, kit and method of the instant invention may be advantageously used for population control in developing countries. In such countries, the availability of an electrosurgical generator, or even of suitable means for powering an electrosurgical generator may be limited. In such environments, it may be desirable to utilize a dedicated special-purpose generator  50  includes a rechargeable power source. In yet another embodiment, generator  50  with the rechargeable power source mounts to instrument  100  such that instrument  100  and generator  50  together form an assembly. 
         [0100]    While the invention has been described in detail and with reference to specific embodiments thereof, it is to be understood that the foregoing description is exemplary and explanatory in nature and is intended to illustrate the invention and its preferred embodiments. Through routine experimentation, one skilled in the art will readily recognize that various changes and modifications can be made therein without departing from the spirit and scope of the invention. 
         [0101]    Other advantages and features will become apparent from the claims filed hereafter, with the scope of such claims to be determined by their reasonable equivalents, as would be understood by those skilled in the art. Thus, the invention is intended to be defined not by the above description, but by the following claims and their equivalents.