TECHNICAL FIELD OF THE PRESENT INVENTION

The present invention relates to a method for performing a vasectomy without mechanically bruising the sensory nerves in the spermatic cord so as to thereby reduce post-procedural pain.

BACKGROUND OF THE PRESENT INVENTION

Vasectomy is a surgical procedure that typically involves the removal of a portion 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; once the vas deferens is interrupted, the sperm cannot be delivered and the man is rendered sterile. Currently used vasectomy methods, such as the No Scalpel Vasectomy (“NSV”), require that each vas deferens be dissected from the scrotum to allow the clinician to occlude and divide the vas duct. Therein, the vas deferens is isolated, extracted, or otherwise delivered from the scrotum via one or two openings formed by puncturing the scrotum and then expanding the opening(s). The vas sheath is then retracted from a portion of the vas duct, which is then hemi-dissected and occluded, preferably by means of mucosal cautery in which the distal end of the filament of a battery powered cautery unit is inserted into each duct lumen and energized so as to create a luminal plug of scar tissue. Alternatively, vas occlusion may involve ligation with a suture or surgical clip. In either case, after the vas is divided, a portion of the duct is optionally excised and one end is isolated in the vas sheath to create a barrier to reconnection of the duct. For example, a layer of the vas sheath may be placed between the two severed ends of the vas duct in order to cover one end but not the other in a technique referred to as “fascial interpositioning”. Once both ends are sufficiently secured, the duct is then returned to the scrotum, the opening through which the vas was accessed is allowed to close and the procedure is deemed complete.

While the procedure appears simple, significant surgical skill is required and complications may result. Most common of these is the arisal of hematomas caused by slow bleeders at the site of the duct occlusion and division. In non-elastic tissue, a small amount of bleeding is quickly stopped by the tension that develops in the tissue. However, because the scrotum is essentially an elastic balloon-like vessel, the hydrostatic pressure necessary to stop bleeding is not present. Accordingly, even the slightest amount of persistent bleeding can cause a tremendously large hematoma. In a similar manner, rough handling of the tissue can lead to significant swelling. Even the most experienced vasectomy surgeon will occasionally encounter these problems.

Other disadvantages inherent in conventional surgical vasectomy, as exemplified by the NSV, include the prolonged surgical duration, which is generally on the order of twenty minutes or more. In addition, conventional vasectomy procedures fail to adequately account for 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 have 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. Finally, because sharp instruments are used, performing a vasectomy on HIV+ patients presents a risk to the surgeon.

In addition, vasectomy patients experience varying levels of post procedure discomfort. This may range from mild discomfort that disappears within a few days, to persistent pain that may require up to several weeks or more to dissipate. The spermatic cord formed by the vas deferens includes an inner vas duct and an outer sheath that surrounds the duct with sensory nerves located primarily in the portion of the sheath distal to the duct when a vasectomy is performed. In a typical NSV, after the vas sheath and the duct contained therein are isolated and exposed at an opening created in the patient's scrotum, an opening is formed in the vas sheath proximal to the surgeon to expose the duct. The duct is then grasped by an instrument and the sheath is retracted away from the clamp to expose a portion of the duct sufficient for occluding and dividing the duct. Retracting (stripping) the sheath from the duct to create this operative space has a tendency to bruise or otherwise damage sensory nerves in the portion of the sheath that is stripped back. Additional injury to the nerves may occur when one end of the duct is returned to the sheath, and the other end is secured outside the sheath so as to provide fascial interpositioning. It is believed that bruising and other trauma to these nerves is a contributing factor to post vasectomy pain.

In the above-referenced co-pending U.S. patent application Ser. No. 16/700,393 to Van Wyk that published as U.S. 2020/0170831 on Jun. 4, 2020 (hereinafter “Van Wyk '831”) and to which the instant application claims priority, the present inventor discloses a method for sealing and dividing a vas duct. The method may be performed with the vas isolated outside the scrotum in the manner of a standard NSV, or, alternatively, in situ, without isolating the vas outside of the scrotum. In the earlier described methods, both the vas duct and the vas sheath are severed after sealing. However, for many clinicians, this is less desirable than retaining an intact vas sheath. Accordingly, there is a need in the art for a vasectomy method that provides reliable occlusion of the vas duct without causing post vasectomy pain due to injury of sensory nerves in the vas sheath.

SUMMARY OF THE PRESENT INVENTION

Disclosed herein are methods for performing a vasectomy in which the multiple steps required to occlude and divide a vas duct in a typical NSV are replaced by a simple sealing process followed by an optional dividing step. According to methods of the present invention, the duct is sealed in two locations spaced a predetermined distance apart without removing the duct from the sheath. Importantly, the sheath is not stripped back to expose a portion of the duct prior to sealing as this stripping process is known to cause injury to the sensory nerves present in the “back side” of sheath, i.e., the region of the sheath behind or distal to the vas duct. This eliminates the associated opportunities for injury to or bruising of nerves located in the vas sheath.

In the methods of the present invention, the vas sheath with its contained duct is isolated and optionally delivered from the scrotum through an opening or openings formed in the scrotum. In certain embodiments, the sheath and duct may be dissected from the scrotum through bilateral openings. In other embodiments, both ducts may be delivered through a single opening formed on the midline of the scrotum. In further embodiments, the duct is addressed in situ, without removal from the scrotum.

In either case, after the sheath and duct are located, a non-conductive or insulated clamp is applied to the duct within the sheath, at the midline of the duct, thereby minimizing contact with delicate sensory nerves present in the “back” or distal region of the sheath. The jaws of a radio frequency (“RF”) bipolar coagulating instrument are positioned around the clamp and closed onto the tissue so as to apply a compressing force. Radio frequency energy from an electrosurgical generator is applied so as to heat the tissue between the bipolar jaws so as to coagulate and seal the tissue. The result is an arcuate region of sealed sheath tissue. Portions of the duct contained within this arcuate region are sealed within the sealed sheath tissue. Tissue circumscribed within the arcuate region (that is, surrounding the non-conductive clamp) is not coagulated. Optionally, while the jaws of the bipolar coagulating device remain in place, this tissue can be removed so as to divide the duct. This may be accomplished using the insulated clamp or another instrument. This removal is not essential since the uncoagulated region is circumscribed by the sealed region and accordingly has no blood flow to it. The tissue will naturally necrose and be absorbed by the body over time.

Because the non-conductive clamp is positioned at about the midline of the duct and the bipolar jaws of the sealing device that surround the clamp are narrow, the number of nerves that are clamped between the jaws is minimized. During sealing of the arcuate region, nerves between the jaws are destroyed by the heat and clamping force. Those that are in sufficiently close proximity to the jaws are destroyed by the RF energy and resulting heat, a process known as radio frequency neurotomy. The RF neurotomy technique is commonly used in other regions of the body to deaden pain producing nerves. In the context of the vasectomy methods of the present invention, it is a desirable byproduct of the sealing method.

In parent publication Van Wyk '831, the present inventor teaches a vasectomy method that may be performed outside of the scrotum, more particularly a method that includes bipolar occlusion of a portion of the vas deferens and subsequent removal of that vas portion that includes both the inner vas duct and the duct's surrounding sheath. In the context of this vasectomy method as previously described, the sealed ends of the separated duct and surrounding sheath are returned to the scrotum and the ends have independent mobility within the scrotum. In contrast, in the methods of the present invention, only a portion of the sheath is sealed and removed along with the vas duct segment. Critically, in the context of the present invention, contact with the distal region (or “back side”) of the vas sheath that contains the bulk of the sensory nerves is avoided. In this manner, the sealed ends of the vas duct, as well as the sealed region of the sheath, remain connected, a preferred result that is akin to that achieved via the “non-divisional” Marie Stopes vasectomy methods described in greater detail hereinbelow. Namely, in the methods of the present invention, like those of Marie Stopes, a physical separation is maintained between the sealed duct ends while the principal nerve-containing region of the outer sheath is preserved.

These and other objectives can be accomplished by the invention herein disclosed. Further 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. To that end, 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. In addition, regarding the specific objectives recited above, 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 objectives herein can be viewed in the alternative with respect to any one aspect of this invention.

