3D digital image microscope system-assisted vasovasostomy and vasoepididymostomy in rats.

Optimal vision and ergonomics are essential factors contributing to the achievement of good results during microsurgery. The three-dimensional (3D) digital image microscope system with a better 3D depth of field can release strain on the surgeon's neck and back, which can improve outcomes in microsurgery. We report a randomized prospective study of vasoepididymostomy and vasovasostomy using a 3D digital image microscope system (3D-DIM) in rats. A total of 16 adult male rats were randomly divided into two groups of 8 each: the standard operating microscope (SOM) group and the 3D-DIM group. The outcomes measured included the operative time, real-time postoperative mechanical patency, and anastomosis leakage. Furthermore, a user-friendly microscope score was designed to evaluate the ergonomic design and equipment characteristics of the microscope. There were no differences in operative time between the two groups. The real-time postoperative mechanical patency rates were 100.0% for both groups. The percentage of vasoepididymostomy anastomosis leakage was 16.7% in the SOM group and 25.0% in the 3D-DIM group; however, no vasovasostomy anastomosis leakage was found in either group. In terms of the ergonomic design, the 3D-DIM group obtained better scores based on the surgeon's feelings; in terms of the equipment characteristics, the 3D-DIM group had lower scores for clarity and higher scores for flexibility and adaptivity. Based on our randomized prospective study in a rat model, we believe that the 3D-DIM can improve surgeon comfort without compromising outcomes in male infertility reconstructive microsurgery, so the 3D-DIM might be widely used in the future.

Clinical application of cross microsurgical vasovasostomy in scrotum for atypical obstructive azoospermia.

Seminal duct obstruction may result in obstructive azoospermia (OA) and severe oligoasthenoteratozoospermia (OAT) (<0.5 million/mL) (Nordhoff et al., 2015). Cases of partial OA and OAT can be treated effectively by microsurgical anastomosis (Goldstein and Kim, 2013) to obtain successful surgical reversal. However, microsurgical vasovasostomy (VV) (Dickey et al., 2015) and vasoepididymostomy (VE) (Peng et al., 2017) are not suitable for patients with atypical OA and poor epididymis conditions or unpredictable obstruction of the distal vas deferens. For those patients, cross anastomosis may be applied instead of routine VE or VV. A single-center, retrospective, comparison study was conducted, which assessed the usefulness of the cross VV (CVV) in the scrotum for indication and efficacy. A total of 77 cases with OA or OAT were included, and 20 cases implemented cross anastomosis, including unilateral CVV (UCVV) in 4 cases, unilateral VE plus CVV (UVE+CVV) in 11 cases, and unilateral VV-based CVV (UVV+CVV) in 5 cases. The other 57 cases received no cross-matching anastomosis. The patency and natural pregnancy rates in one year were 75.0% and 50.0%, respectively, in the UCVV group; 54.5% and 27.3%, respectively, in the UVE+CVV group; and 60.0% and 40.0%, respectively, in the UVV+CVV group. The CVV in the scrotum in the selected patients with OA and severe OAT could yield good results. We regard the CVV in the scrotum as an efficacious operation with a lower risk of injury in cases of atypical OA.

Angled vas cutter for vasovasostomy: technique and results.

OBJECTIVE: To describe the technique and results of bilateral vasovasostomy using a 3-mm vas cutting forceps angled at 15° (catalog no. NHF-3.15; ASSI) for vasal transection. DESIGN: Retrospective chart review. Institutional review board approval was granted by Western Institutional Review Board. SETTING: Single vasectomy reversal center. PATIENT(S): Men who underwent a bilateral vasovasostomy at a single institution by a single surgeon between 2001 and 2012 and had a minimum of one semen analysis postoperatively or a reported natural conception. INTERVENTION(S): Before September 14, 2010, a straight-edge vas cutter was used on all vasovasostomy connections; 375 men received a bilateral vasovasostomy and met follow-up criteria. Beginning on September 14, 2010, an angled cutter was used on all vasovasostomy patients, with 194 men meeting the exclusion criteria. MAIN OUTCOME MEASURE(S): A minimum of 1 × 10(6) sperm reported on a postoperative semen analysis, or a reported natural conception was used to establish patency. RESULT(S): The overall vasovasostomy patency rate using the angled vas cutter was 99.5% and was 95.7% using the straight vas cutter. CONCLUSION(S): The development of an angled vas cutter provides an increased surface area for vasal wound healing to allow for larger tissue diameter for better healing, resulting in high patency rates after vasovasostomy.

One-layer vasovasostomy: microsurgical versus loupe-assisted.

OBJECTIVE: To compare the outcomes of microsurgical versus loupe-assisted technique for vasectomy reversal. DESIGN: Retrospective comparative study with randomization. SETTING: University hospital male infertility clinic. PATIENT(S): Fifty men with obstructive azoospermia after vasectomy. INTERVENTION(S): One-layer vasovasostomy with microscope (group I) or optical loupe (group II). MAIN OUTCOME MEASURE(S): Patency, pregnancy, operation time, postoperative stricture. RESULT(S): Mean operation time was 106.4±10.3 minutes in group I and 78.3±5.7 minutes in group II, showing a statistically significant difference. Analysis of semen sampled from men, who succeeded in getting vasal patency, was performed finally at the sixth month after surgery and showed sperm concentrations of 21.5 million/mL and 20.7 million/mL and sperm motilities of 32.5% and 30.8% in groups I and II, respectively, without a statistical significance. Patency rates were 96% (24 out of 25) in group I and 72% (18 out of 25) in group II, showing a statistically significant difference. Pregnancy rates were 40% (10 out of 25) in group I and 28% (7 out of 25) in group II. There was no statistically significant difference in pregnancy rate between the two groups. Postoperative vasal stricture occurred in four patients, all of them from group II. There was no operation-related complication, such as hematoma or wound infection. CONCLUSION(S): Microscopic technique yielded a higher patency rate than loupe-assisted technique, possibly by reducing the chance of postoperative vasal stricture.

Video technique for human robot-assisted microsurgical vasovasostomy.

Previous studies have shown that robot-assisted microsurgical vasovasostomy (RAVV) has technical advantages over pure microscopic vasovasostomy (MVV) in animal and human models. This study presents a video technique and initial results for RAVV in 20 human cases compared with 7 MVV cases by a single fellowship-trained microsurgeon from July 2007 to June 2009. A three-layer 10-0 and 9-0 suture anastomosis was performed with up to 22 months follow-up (mean 3 months). Mean operative duration for the RAVV cases was 109 and 128 minutes for MVV (p = 0.09). At 2 months postoperatively, all patients were patent. Mean sperm count was 54 million in RAVV and 11 million in MVV (p = 0.04). The use of robotic assistance in microsurgical vasovasostomy may have potential benefit over MVV in decreasing operative duration and significantly improving early semen analysis measures. Further evaluation and longer follow-up is needed to assess its clinical potential.

Minimally invasive vas surgery using a newly designed double-ringed clamp.

INTRODUCTION: We have recently designed a novel surgical instrument, a double-ringed clamp (Moon's clamp), with which the vas deferens can be located and isolated both simply and safely while minimizing unnecessary injury to the surrounding tissue. MATERIALS AND METHODS: With the use of the Moon's clamp, we successfully performed 1,140 cases of simplified, minimally invasive vasectomy and 216 cases of mini-incision vasectomy reversals (vasovasostomies) without any significant complications. CONCLUSION: This surgical technique, using Moon's clamp, may be effective in reducing the operative time, the postoperative complications and the recovery time after different types of vas surgeries, such as vasectomy or vasectomy reversal.

New nonabsorbable stent versus a microsurgical procedure for vasectomy reversal: evaluating tissue reactions at the anastomosis in rabbits.

OBJECTIVE: To investigate whether a newly designed nonabsorbable polymeric stent for the reconstruction of the vas deferens provided less stricturing at the site of the anastomosis in comparison with the conventional microsurgical reconstruction of the vas deferens. DESIGN: Prospective randomized study in 26 rabbits, comparing the one-layer microscopic sutured procedure with a biocompatible stent. SETTING: University animal laboratory center. INTERVENTION(S): Pre- and postoperative average total sperm count, motility, and progressive motile sperm density (PMSD) levels were measured. Histologic sections were taken from the area of the anastomosis, testes, and epididymi after final semen analysis. MAIN OUTCOME MEASURE(S): Rates of stricture and semen parameters. RESULT(S): The vas deferens of the rabbits that received a stent showed an inflammatory reaction within the vas wall adjacent to the stent. Transmural histiocytic or eosinophilic reactions were seen in 2/13 (15%) of the stented animals, with atrophy of the epithelium. Histologic cross-sections of the stented vas deferens demonstrated patency. Microscopically sutured rabbits showed more partial obstructions at the site of the anastomosis (5/13 [38%]) with transmural infiltration of lymphocytes and histiocytes. Despite these partial obstructions the vasa were patent. There was a statistically significant difference in favor of the stent with respect to the total sperm count (P=.05). No differences were seen in motility (P=.057) or PMSD (P=.13). CONCLUSION(S): The newly developed stent provided patency rates comparable with the conventional one-layer microscopic procedure but showed significantly less stricturing of the anastomoses.

Robotic-assisted vasovasostomy: a two-layer technique in an animal model.

OBJECTIVES: To assess the feasibility of a multilayered robotic-assisted vasovasostomy (RAVV) in a rabbit model. Microscope-assisted vasovasostomy (MAVV) is a technically challenging procedure. Robotics may be a surgical adjunct that helps overcome the microsurgical challenges, which include fine suture, delicate instruments, and tremor. A recent survey revealed that most urologists use a multilayered technique for vasovasostomies. METHODS: A surgeon performed eight vasovasostomies with 10-0 suture and a two-layer technique using an in vivo rabbit model-four were MAVV using conventional microsurgical instrumentation and four were RAVV using the da Vinci robot. Performance measures and adverse haptic events were recorded. Patency was evaluated by passing a 2-0 Prolene suture through the anastomoses. RESULTS: The mean operating time for the total procedure and for the mucosal layer only was longer for RAVV than for MAVV (75 versus 42 minutes, P = 0.03 and 38 versus 23 minutes, P = 0.03, respectively). The needle passes required for the mucosal layer and the number of mucosal and muscularis sutures were similar in both groups (9.5 versus 8.8 passes, P = 0.34; 4 versus 4, P >0.99; and 7 versus 6.3, P = 0.2, respectively). Unlike MAVV, no tremor was appreciated during RAVV. No adverse haptic events were observed in either group. All anastomoses were patent, and all rabbits were free of any crush injury. CONCLUSIONS: A multilayered RAVV can be performed in an in vivo rabbit model. Although it was associated with increased operative times, the absence of adverse haptic events and comparable patency rates continue to suggest a role for robotics in microsurgery.

The use of a newly designed nonabsorbable polymeric stent in reconstructing the vas deferens: a feasibility study in New Zealand white rabbits.

OBJECTIVES: To investigate the use of a newly designed stent in the reconstruction of the vas deferens. MATERIALS AND METHODS: In 26 New Zealand White rabbits, 13 conventional one-layer microscopic reconstructions were compared with 13 stented reconstructions of the vas deferens. The newly designed nonabsorbable polymeric stent was shaped to facilitate the rejoining of the two loose ends of the vas deferens, using a central ridge to prevent migration. Semen was collected before and after surgery, using an artificial vaginal system (26 samples before and 115 after surgery). The individual and average total sperm count, motility and progressive motile sperm density (PMSD), were compared after surgery for both groups. After the final semen analysis, rabbits were killed and patency was assessed histologically at the site of the anastomosis. RESULTS: After an initial decline the mean total sperm count increased in both groups. The increase was significantly larger (P = 0.05) in the stented rabbits. The mean motility and PMSD showed no significant differences between both groups (P = 0.11 and 0.71, respectively). Histological examination of the anastomosed area showed partial obstruction (>50% narrowing of the original lumen) in five of the 13 conventionally treated rabbits, with no strictures in the stented group. Despite the narrowing in the conventional group the patency rates were not affected. The mean (range) operating time for the conventional and stented groups was 132 (99-168) and 98 (62-113) min, respectively (P < 0.001). CONCLUSIONS: The total sperm counts, motility and PMSD showed no or little difference after surgery between the conventional and stented rabbits. The stented reconstruction was easy, had no secondary stricturing and reduced the operating time.

Robot-assisted vasovasostomy.

Robot-assisted vasovasostomy is an attractive alternative to traditional microscopic techniques for several reasons. The normal physiologic tremor is removed and greater ease and precision of suture placement is possible. The training period or learning curve for robot-assisted vasovasostomy is shorter than traditional microscopic techniques. This will allow more surgeons to provide quality technical surgical care for their patients. Additional costs are only a few hundred dollars. As surgical robots become increasingly available and used for a wider variety of procedures, the feasibility of robotic vasovasostomy becomes more realistic and vasoepididymostomy is likely. Although robotic surgery has improved prostate surgery, its contribution to microsurgical technique has the potential for a more profound impact.

Robotic microsurgical vasovasostomy and vasoepididymostomy: a prospective randomized study in a rat model.

PURPOSE: Microsurgical vasovasostomy and vasoepididymostomy remain technically challenging procedures. Refinements in technique have continually improved patency and pregnancy rates for the 2 procedures in experienced hands. Advances in surgical robotics produced the Da Vinci robot (Intuitive Surgical, Inc., Sunnyvale, California) with motion reduction and no tremor, features that may improve outcomes in microsurgery. We report a randomized prospective study of vasoepididymostomy and vasovasostomy using the Da Vinci robot in rats. MATERIALS AND METHODS: A total of 24 adult male Wistar rats underwent vasectomy through a midline abdominal incision. Two weeks later the animals were randomized to microsurgical multilayer vasovasostomy, longitudinal vasoepididymostomy or robotic vasovasostomy and vasoepididymostomy groups. Outcomes measured included surgical time, complications, patency and sperm granuloma formation at 9 weeks. RESULTS: Animals were sacrificed 9 weeks after microsurgery. There were no significant differences in complications among the groups. Robotic vasovasostomy was significantly faster than the conventional microsurgical technique (68.5 vs 102.5 minutes, p = 0.002). The robotic and microsurgical vasoepididymostomy groups did not differ significantly in time. Patency rates were 100% for the robotic vasovasostomy and vasoepididymostomy groups, and 90% in the microsurgical vasovasostomy and vasoepididymostomy groups. These differences were not significant. Sperm granulomas were found in 70% of microsurgical vasovasostomy anastomoses and 27% of robotic vasovasostomy anastomoses (p = 0.001). No significant difference in the sperm granuloma rate was found between the robotic or microsurgical vasoepididymostomy groups (42% and 50%, respectively, p = 0.37). CONCLUSIONS: To our knowledge we report the first randomized prospective study using the Da Vinci robot for microsurgery. We believe that the improved stability and motion reduction during microsurgical suturing with the robot helped achieve excellent patency rates for vasovasostomy and vasoepididymostomy. The robot may also allow experienced microsurgeons to perform microsurgical procedures in patients at remote locations where no experienced microsurgeons are available.

A polymeric mini-stent designed to facilitate the vasectomy reversal operation. A rabbit model study.

Vasectomy has become popular since it is the safest surgical method for contraception. It is known that approximately 6% of the men that undergo vasectomy will seek reversal (vasovasostomy). This operation is, however, technically demanding and relatively time-consuming. This study was based on the hypothesis that a polymeric mini-stent can facilitate and accelerate vasovasostomies. A mini-stent was manufactured out of a crosslinked hydrogel biomaterial, which was synthesized from N-vinyl-pyrrolidinone (NVP), n-butylmethacrylate, and (triethyleneglycol) dimethacrylate. The device was tested with 28 rabbits, which were divided over two equal groups. In one group, the vasa deferentia were dissected and reanastomosed via microsurgical one-layer technique (end-to-end group). In the other group, the vasa deferentia were dissected and reattached through implantation of the mini-stent. Sperm counts revealed 100% patency in both groups, i.e. all vasovasostomies were successful. It was experienced that the operation was easier and faster in the case of the mini-stent, probably since the mini-stent keeps the lumens of both vas ends exactly in line during suturing. This study demonstrates the feasibility of the mini-stent. Further work is necessary to evaluate the utility of this approach for clinical vasovasostomies.

The application of laser techniques to vasectomy reversal surgery.

OBJECTIVE: A review of the application of laser technology to vasectomy reversal surgery. SUMMARY BACKGROUND: Modern methods of vasectomy reversal that employ microsurgical techniques have resulted in a high reported success rate. However, the procedure is tedious and time consuming. Laser technology offers the possibility of simplifying the procedure and reducing operative time, with possibly even better results. CONCLUSIONS: Application of lasers in vasovasostomy for vasectomy reversal is still in its early development. Several animal and human studies have been conducted with mixed results. Contained clinical trials will be necessary to prove the benefit of the laser in this surgical setting.

Vaso-vasostomia microquirurgica del conducto deferente: un modelo experimental / Microsurgical vaso-vasostomy of the deferent duct: an experimental model

Estudio modelo experimental en seis conejos machos de 5 meses de edad mediante la técnica microquirúrgica de anastomosis con el uso de un microtubo guiador que facilita el manejo de los deferentes y su sutura, comprobando la integridad de la línea de sutura (FV)

Sutureless vasovasostomy: new technique using experimental microclip in rat model.

Standard microscopic suture vasovasostomy represents a challenge to many urologists. It is technically demanding, and requires two to five hours of operative time. In an attempt to decrease the technical demand and the time requirement, we report the use of a microvascular anastomotic clip and compare this microclip to a standard eight-suture nonstented technique and a six-suture stented technique using a hollow, absorbable 0.5-mm polyglycolic acid stent. The control group with suture required an average of 38.5 minutes per anastomosis for the nonstented group and twenty-two minutes for the stented group. The clip group required 7.6 minutes for the unstented vasovasostomy and 6.5 minutes for the stented vasovasostomy. We obtained a 91 percent patency rate for the stented clip group and 100 percent patency for the unstented clip group. In a rat vasovasostomy, the operative time as well as the inherent technical demand were significantly reduced.

Tissue reconstruction with nonpenetrating arcuate-legged clips. Potential endoscopic applications.

A new system for tissue approximation consisting of a nonpenetrating arcuate-legged clip applied to everted tissue edges to form an elastomeric flanged joint is described. The flanged joint has unusual physical and morphologic properties. Novel systems for tissue eversion, clip application and clip removal have been tested at the micro scale in blood vessels and the rat vas deferens (vasovasostomy). Human applications have been successful (cerebrovascular reconstruction, free-flap transfer, skin grafting, A-V access). The system is biologically and technically equivalent to or superior to the needle-and-suture technique. Avoidance of intimal or mucosal penetration or intraluminal foreign body is associated with prompt wound healing and the reconstitution of tubular integrity. The system is readily adaptable for endoscopic surgical reconstructions, providing the surgeon with enhanced reconstructive abilities.

Experimental study of hollow, absorbable polyglycolic acid tube as stent for vasovasostomy.

Bilateral vasovasostomy in 16 rats permitted evaluation of a microsurgical technique using an original absorbable hollow stent made of polyglycolic acid. Advantages of this stent included ease of anastomosis, maintenance of luminal patency, satisfactory approximation of vasal ends, and reduction of perivasal inflammation possibly due to reduction of extravasation of sperm. Absorbable stents were eliminated within four weeks of placement, and patency was confirmed by histologic studies performed two, four, and six weeks after vasovasostomy.