Vas occlusion by tantalum clips and its comparison with conventional vasectomy in man: reliability, reversibility, and complications. Vasectomy by ligation and excision, with or without fascial interposition: a randomized controlled trial [ISRCTN77781689]. Peroperative irrigation of the vas deferens during vasectomy. A phase II randomized controlled trial of a novel male contraception, an intra-vas device. Sterile water irrigation of the distal vas deferens at vasectomy: does it accelerate clearance of sperm? A prospective randomized trial. Intra-vas deferens bupivacaine for prevention of acute pain and chronic discomfort after vasectomy.
Occlusion of the vas deferens has been carried out by applying tantalum clips in 60 men. Another 50 men were vasectomized conventionally and served as controls. Vasography showed that two clips were required on each vas to bring about perfect and firm occlusion. The incidence of postoperative infection and other complications was much lower in the clip-occluded cases. Under a long-term follow-up, 10% of the conventionally vasectomized men were dissatisfied with the operation as compared with 2% of the clip-occluded group. Both groups became azoospermic within 3 months and the failure rate was zero. Removal of the clips not only was difficult but left the vas compressed and leaking. The method cannot, therefore, be considered reversible by itself. However, recanalization could easily be achieved by end-to-end anastomosis after excision of the small clipped segment or by side-to-side anastomosis without any excision. This, damage to the neuromuscular apparatus of the vas may be minimized. Male sterilization by clip occlusion has the advantages of minimal surgical intervention, shorter operative time, safety from postoperative infection, and easier recanalization if desired. Randomized controlled trials comparing different vasectomy occlusion techniques are lacking. Thus, this multicenter randomized trial was conducted to compare the probability of the success of ligation and excision vasectomy with, versus without, fascial interposition (i.e. placing a layer of the vas sheath between two cut ends of the vas).
                The trial was conducted between December 1999 and June 2002 with a single planned interim analysis. Men requesting vasectomies at eight outpatient clinics in seven countries in North America, Latin America, and Asia were included in the study. The men were randomized to receive vasectomy with versus without fascial interposition. All surgeons performed the vasectomies using the no-scalpel approach to the vas. Participants had a semen analysis two weeks after vasectomy and then every four weeks up to 34 weeks. The primary outcome measure was time to azoospermia. Additional outcome measures were time to severe oligozoospermia (<100 000 sperm/mL) and vasectomy failure based on semen analyses.
                We halted recruitment after the planned interim analysis, when 841 men had been enrolled. Fascial interposition decreased time to azoospermia (hazard ratio [HR], 1.35; P < 0.0001) and time to severe oligozoospermia (HR, 1.32; P < 0.0001) and reduced failures based on semen analysis by about half, from 12.7% (95% confidence interval [CI], 9.7 to 16.3) to 5.9% (95% CI, 3.8 to 8.6) (P < 0.0001). Older men benefited less from fascial interposition than younger men in terms of the speed of achieving azoospermia. However, the number of vasectomy failures was reduced to a similar degree in all age groups. Slightly more adverse events occurred in the fascial interposition group, but the difference was not significant. These failure rates may appear high to practitioners in countries such as the USA, but they are similar to results from other careful studies of ligation and excision techniques.
                Fascial interposition significantly improves vasectomy success when ligation and excision is the method of vas occlusion. A limitation of this study is that the correlation between postvasectomy sperm concentrations and risk of pregnancy is not well quantified. In 59 consecutive vasectomies for the purpose of sterilization, one-half, chosen by random numbers, received an irrigation of the vas deferens with 40 ml of sterile water on each side. Afterwards, the men sent in every fourth ejaculation, until two consecutive samples were without spermatozoa. The postoperative sperm samples were examined microscopically without knowing whether the man belonged to the treated group or the control group. The irrigation procedure did not shorten the time needed to reach azoospermia. The aim of this study was to introduce a novel male contraceptive method, an intra-vas device (IVD), and to assess the efficacy, safety and satisfaction of recipients compared with no-scalpel vasectomy (NSV). A phase II randomized controlled trial was conducted in China in 2003. Two hundred and eighty-eight male subjects seeking vasectomy were randomly assigned to the IVD or NSV group. Follow up included a telephone questionnaire on the 14th postoperative day and visits at the third and 12th postoperative months. The follow-up rates at the three time points were 100%, 100% and 96.5% respectively. There was no technical failure in any subject. The surgical conditions were similar in both groups, but the IVD group experienced an additional 5 min of operative time (p<0.001). The IVD group recovered normal activity and sexual intercourse more rapidly (both p<0.05). The azoospermia rate was lower in the IVD group than in the NSV group at the third and 12th postoperative months. The rate of contraceptive success based on semen analyses was similar in both groups, especially at the 12th postoperative month (94.3% in the IVD group vs. 98.6% in the NSV group; p=0.054). The IVD group had less risk of complications (i.e. pain, congestive epididymitis and sperm granuloma). More subjects reported satisfaction with IVD sterilization than with NSV. The two procedures were similar in terms of surgical complications. The IVD was slightly less effective, but had a lower risk of later adverse events than the NSV technique. The IVD group also reported a higher level of satisfaction. To assess the effect of irrigation of the distal vas deferens with sterile water at the time of vasectomy on sperm clearance. Is it possible to accelerate clearance and avoid the problem of lingering sperm?
                Two hundred men undergoing vasectomy were randomized to receive either a standard vasectomy or vasectomy plus irrigation of each vas deferens with sterile water. The interval between vasectomy and the production of two azoospermic semen samples was recorded.
                Overall, 37 patients were excluded for failing to follow the postvasectomy protocol for semen analysis, leaving 87 in the control group and 76 who received vasal irrigation. No statistically significant differences existed between the two groups with regard to the mean time to clearance (26.4 weeks, control group versus 28.6 weeks, flush group), proportion clear at 16 weeks (29% versus 21%), or proportion with lingering sperm at 40 weeks (22% versus 26%).
                Irrigation of the vas deferens with sterile water does not accelerate the clearance of spermatozoa after vasectomy. Men wishing to undergo vasectomy must be counseled about the possibility of lingering sperm. We have studied the use of intra-vas deferens local anaesthesia in 70 patients undergoing vasectomy as day-case patients. Patients were allocated randomly to either a control or treatment group. In the treatment group, 0.5% bupivacaine 1 ml or 0.9% saline 1 ml was injected into the lumen of the right or left vas deferens in a randomized blinded design. The control group did not receive an injection. Patients were discharged with a questionnaire for recording visual analogue scores (VAS) for both the right and left sides to be scored on days 1 and 7 after operation. One year after the procedure a second questionnaire was sent out asking about the presence or absence of chronic testicular discomfort, its duration and any surgical intervention required to relieve it. There were no differences between the control group and the saline side of the treatment group in VAS scores on both day 1 and day 7 after operation or in the incidence and duration of chronic testicular discomfort (mean 30 (SD 53) and 34 (50) days, respectively). The VAS scores were, however, significantly less (P < 0.005) and testicular discomfort was absent on the bupivacaine-treated side.
For vas occlusion with clips or vasectomy with vas irrigation, no conclusions can be made as those studies were of low quality and underpowered. Fascial interposition reduced vasectomy failure. An intra-vas device was less effective in reducing sperm count than was no-scalpel vasectomy. RCTs examining other vasectomy techniques were not available. More and better quality research is needed to examine vasectomy techniques.