114 Parviz K. Kavoussi Department of Reproductive Urology, Austin Fertility & Reproductive Medicine/Westlake IVF, Austin, TX, USA Approximately 500 000 men in the United States undergo vasectomy every year. With a divorce rate of approximately 50% in the United States, up to 6% of men who have undergone vasectomy will elect to have the vasectomy reversed some time in their lifetime [1, 2]. Vasectomy reversal (VR) was described in the 1930s and the use of the operative microscope for magnification to assist in the anastomosis was applied in the 1970s with significantly improved patency rates [3–5]. For years, people have been dreaming of robots. Whether it has been for science fiction or for practical uses, the idea of robots mechanically assisting us with tasks has seemed appealing. We used to hear people say “some day robots will do surgery for us.” This has not necessarily become the case, but robots are finding more utility in assisting us with surgery. The da Vinci® system began with uses for gross surgical procedures and has expanded its utility to microsurgery. In urology, this particularly lends itself to VR. Surgery that we initially tried with the naked eye advanced through multiple technologies including optical loupes, operative microscopes, and now the operative robot. The advantages of using robotics to assist with microsurgery include the ability of devices such as EndoWrists® to work with seven degrees of freedom, enabling movements that the human hand and wrist cannot make, an ergonomic design for the surgeon which is less fatiguing and that may enhance performance, the scalability of motion, and high‐definition 3D optimal visualization of a microsurgical field. Once the learning curve for robotic microsurgery is mastered by microsurgeons it should improve operative times as well. Understanding the anatomy of the vas deferens and the epididymis is paramount to a successful outcome with VR and the same is true for robot‐assisted vasectomy reversal (RAVR). The vas deferens is a tubular structure derived embryologically from the mesonephric (Wolffian) duct. It extends from the distal end of the cauda of the epididymis and the tortuous segment leaving the epididymis for the first 2–3 cm is known as the convoluted vas deferens. The vas deferens measures between 30 and 35 cm in length from the cauda epididymis to the ejaculatory duct, where it terminates. It travels behind the vessels in the spermatic cord, posteriorly. Depending on the segment, the lumen of the vas deferens ranges between 0.2 and 0.7 mm in diameter [6]. The deferential artery, a branch of the superior vesical artery, supplies the vas deferens [7]. The venous drainage of the scrotal vas deferens is via the deferential vein, which drains into the pampiniform plexus. The venous drainage of the pelvic vas deferens is via the pelvic venous plexus. The lymphatic drainage travels to the external and internal iliac nodes. Sperm travel through the epididymis from the testis to reach the vas deferens. If uncoiled, the tightly coiled tubular epididymis would stretch to 3.5–4.5 m long. The three regions of the epididymis are characterized as the caput (head), the corpus (body), and the cauda (tail). The caput epididymis comprises 8–12 ductuli efferentes from the testis. The most distal portion of the cauda epididymis is continuous with vas deferens. The arterial supply of the caput and corpus epididymis is from a branch of the testicular artery, which further divides to supply the superior and inferior epididymal branches [8]. Branches from the deferential artery provide vascular supply to the cauda epididymis. Venous drainage of the corpus and cauda epididymis are via the vena marginalis of Haberer, draining into the pampiniform plexus via the vena marginalis of the testis, or through cremasteric or deferential veins [8]. Lymphatic drainage of the caput and corpus epididymis is through channels that travel with the internal spermatic vein, draining to the preaortic nodes. Lymphatic channels from the cauda epididymis join those leaving the vas deferens to drain into the external iliac nodes. Prior to undergoing RAVR, the level of spermatogenesis in the patient should be assessed. A history of fertility from prior to the vasectomy is typically considered sufficient. A full physical examination should be performed prior to RAVR with special attention to the genital examination. Testicular volumes and consistency should be assessed. Firm, normal‐volume testicles are indicators of good spermatogenesis, whereas small or soft testes may indicate some spermatogenic deficiency. It is not uncommon for the epididymis to feel dilated on examination in men who have undergone vasectomy. Epididymal induration may indicate the need for robot‐assisted vasoepididymostomy (RAVE). When a large vasectomy defect or gap can be palpated, this should prompt counseling for a more extensive dissection to perform a tension‐free anastomosis. When a sperm granuloma is palpated at the testicular end of the vas deferens, this indicates leaking of sperm as a result of a pop‐off valve‐like mechanism to decrease intraepididymal pressures. Sperm granuloma are associated with better outcomes with VRs, suggesting that the epididymis has protected itself by decreasing intraluminal pressures [9]. When physical examination reveals a very long vasectomy defect, a segment that has been removed, the surgeon should consider a nonstandard incision approach [10]. As more men are being diagnosed with hypogonadism and are being treated with testosterone replacement therapy, adversely impacting the level of spermatogenesis, medical management must be considered prior to performing RAVR in these men. Testosterone replacement should be discontinued, testicular salvage therapy with clomiphene citrate or human chorionic gonadotropin (hCG) should be implemented for approximately three months, and then RAVR can be performed with acceptable outcomes [11]. The obstructive interval since the vasectomy has a significant impact on the type of RAVR required, whether robot‐assisted vasovasostomy (RAVV) or RAVE. This has been shown to affect patency rates in many studies on VR; in general, the longer the interval since vasectomy, the more challenging the candidate is considered to be for VR [12, 13]. However, in the hands of a surgeon who is proficient in both RAVV and RAVE, RAVR should still be offered to men with longer obstructive intervals. In technically skilled hands, success rates remain high regardless of the type of VR performed in men with obstructive intervals over 10 years [14]. Multiple nomograms have been constructed to predict the type of VR required and patency rates. Factors evaluated to assess these outcomes include patient age, testicular volume, the presence of sperm granuloma, and obstructive interval [15, 16]. There is a question over the accuracy of the nomograms and their utility with inconsistent data [17, 18]. As it is not typically possible to predict preoperatively if vasoepididymostomy will be required, VR should only be performed by surgeons skilled in both vasovasostomy and vasoepididymostomy [19, 20]. Before a man undergoes RAVR, his female partner should undergo a fertility evaluation, with counseling on female age and ovarian reserve impact on the couple’s fertility potential [10]. Semen analysis with a centrifuged evaluation of the pellet may be performed prior to VR. Ten percent of these centrifuged pellets will reveal whole sperm, suggesting good outcomes and indicating that sperm will be found in the vas deferens at least unilaterally at the time of VR [21]. When the semen analysis reveals low semen volume, transrectal ultrasound should be performed to rule out the possibility of a concomitant ejaculatory duct obstruction. When the physical examination indicates potential spermatogenic deficiency with findings such as small, soft testicles, a serum follicle‐stimulating hormone (FSH) should be obtained. An elevated FSH indicates spermatogenic failure, a potentially poor outcome with VR, and may be a predictor of the need for higher levels of assisted reproduction care [22]. Serum antisperm antibody (ASA) testing is not recommended as a routine preoperative test prior to VR. Approximately 60% of men develop circulating ASAs after bilateral vasectomy [23]. Preoperative ASA testing is of unproven value, and the high postoperative conception rate after VR questions the impact of circulating ASAs on fecundability [24–31]. RAVR may be performed with local, regional, or general anesthesia [10]. As meticulous robot‐assisted microsurgical technique and tissue handling is mandated for superior outcomes, general anesthesia is the anesthesia of choice to minimize patient movement and to optimize patient comfort. Although RAVR can be performed with local anesthesia with sedation, this tends to result in more motion, which makes a challenging operation even more challenging. If a RAVE or a more difficult anastomosis is required, it may require lengthy operative times which can be difficult for the patient under local anesthesia or sedation. The patient is placed in the supine position. After induction of general anesthesia, all pressure points are padded and the scrotum is shaved, prepared, and draped. Once the vasa are prepared and ready for the anastomosis, the operative robot is brought in from the patient’s right side at a 90° angle with the 0° camera placed directly over the operative field of the scrotal incision, perpendicular to the floor (Figure 114.1). Figure 114.1 The robotic system is positioned at a 90° angle to the patient with the camera positioned directly above the operative field (view from console). The scrotal incision provides the most direct access to the vasectomy defect to isolate the ends of the vas deferens for anastomosis. In scenarios with high vasectomy defects or long vasectomy defects, the incision may be extended toward the external inguinal ring. The testis may be delivered in cases with a very low vasectomy defect or when a RAVE is deemed necessary. Mini‐incision VR using no‐scalpel vasectomy principles has been evaluated and found to have comparable patency rates with less postoperative pain and faster functional recovery [32, 33]. Mini‐incision RAVR is the author’s approach of choice, using an incision less than 1 cm. In men who have previously undergone varicocele repair or inguinal hernia repair, the surgical approach to RAVR will vary. If a man has undergone varicocele repair for orchialgia or for hypogonadism with a concomitant vasectomy, the RAVR should be approached through the prior subinguinal incision after confirming that the vasectomy was performed subinguinally by previous operative report. In men who have suspected vas deferens obstruction from previous inguinal herniorrhaphy, approaching the RAVR through the previous scar will lead to the site of the vas deferens obstruction. RAVR following herniorrhaphy has also been performed intra‐abdominally with robot assistance. This is a prime example of the robotic platform’s ability to improve access to a difficult vas deferens repair [34, 35]. Once the vasectomy defect is isolated through the incision, the abdominal and testicular ends of the vasa may be isolated with the use of vessel loops. Care should be taken to not strip the vas deferens of the perivasal adventitia to maintain the microvasculature supply to the vas deferens. The abdominal and testicular ends of the vas deferens are adequately mobilized, with its adventitia intact, to allow for a tension‐free anastomosis. The obstructed segment of the vas deferens at the vasectomy defect site may be excised or excluded. Care should be taken to preserve the deferential artery during this maneuver. After the testicular and abdominal ends of the vas deferens are isolated, the testicular end of the vas deferens is sharply divided at an exact 90°. The divided end of the vas deferens should have the muscularis and the mucosa inspected to confirm that there is a healthy surface to anastomose without fibrosis or scar. Fluid from the testicular lumen of the vas deferens is then applied to a glass slide, diluted with a drop of saline, and examined under the light microscope (Figure 114.2). The quality of the fluid from the testicular end of the vas deferens and the microscopic findings dictate whether a RAVV or a RAVE should be performed. If microscopic examination of the vasal fluid reveals whole sperm with tails (Figure 114.3) or when there is copious, clear fluid from the vas deferens but no sperm are found in the fluid, RAVV should be performed. If fluid is not present, a 24 gauge angiocatheter sheath is cannulated into the lumen of the testicular end of the vas deferens and barbotage is performed with 0.1 ml of saline, which is then microscopically examined. If there is no significant vasal fluid or sperm identified after this maneuver, a RAVE should be performed. When the vasal fluid appears thick and toothpaste‐like in quality, sperm are typically not found on microscopic examination of the fluid, and RAVE is indicated. Figure 114.2 Obtaining vasal fluid from the testicular end of the vas deferens to evaluate under the microscope. Figure 114.3 Whole sperm visualized under the light microscope in the vasal fluid. Over 90% of VRs will be successful when sperm fragments (sperm heads and/or short tails) are found in the vasal fluid intraoperatively, regardless of the fluid quality. This success rate surpasses the expected success rate with vasoepididymostomy [36, 37]. Sperm quality has been categorized in five grades to describe the findings in the vasal fluid. Grade 1 reveals mainly normal motile sperm, grade 2 mainly normal nonmotile sperm, grade 3 mainly sperm heads, grade 4 only sperm heads, and grade 5 no sperm [38, 39]. The abdominal end of the vas deferens is divided in a similar manner. The lumen is gently cannulated with a 24 gauge angiocatheter sheath and saline is injected into the lumen to demonstrate patency (Figure 114.4
Robot‐Assisted Vasectomy Reversal
Introduction
Anatomy
Preoperative evaluation/physical examination
Preoperative laboratory testing
Anesthesia
Patient positioning
Incision approaches
Preparing the vas deferens
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