Vasovasostomy: Past, Present and Future

Vol. 112, ,Jul,; Printed in US.A.

THE ,JOURNAL OF UROLO(~Y

Copyright© 1974 by The Williams & Wilkins Co.

VASOVASOSTOMY: PAST, PRESENT AND FUTURE JOSEPH E. MONTIE*

AND

Vasectomy for sterilization is being performed at a rate of more than 500,000 per year in the United States. Therefore, it is reasonable to assume that with this number of vasectomies we will be asked to reverse the procedure frequently in the future. Unfortunately, the postoperative vasovasostomy success rate, as determined by pregnancy, is still only 40 to 50 per cent at best and many urologists are reluctant to perform the operation because of its low success rate. VASOVASOSTOMY IN THE PAST

In 1948 O'Conor sent questionnaires to 1,240 recognized specialists asking them the number of vasovasostomies they have performed and their success rate. 1 He received 750 replies: 615 surgeons

BRUCE H. STEWARTt around the world but most surgeons use an intravasal stent that is exteriorized perforating the proximal vas and scrotal skin then anchored to the scrotum (fig. 1). The stenting material extremely variable, as is the suture material for the reanastomosis. Exteriorized intravasal stents are generally left in place for 7 to 10 days, which is the time Schmidt found was required for tion of the anastomotic line. 2 Table 1 summarizes the results and the stenting and suture material used in several reports on vasovasostomy. 3 -s High percentages of anatomic patency ( determined postoperative appearance of sperm in are achieved in most series. However, the postoper ative pregnancy rate is about 40 to 50 per cent. There are several possible explanations for the less

FIG. 1. Vasovasostomy using exteriorized intravasal stent, with stent perforating proximal vas and scrotal skin

had neYer performed the operation, while 135 surgeons had done 420 vasovasostomies, with 160 reported successful results (over-all success rate of ;33 per cent, criteria for success being the appearance of spermatozoa in the ejaculate). VASOVASOSTOMY AT PRESENT

The number of vasovasostomies performed in the United States since 1948 has increased and it is appropriate to review the results in recently reported series. Multiple techniques are being used Accepted for publication January 11, 1974. Read at annual meeting of South Central Section, American Urological Association, Houston, Texas, September 2:1-27, 1973. * Requests for reprints: Department of Surgery, Division of Urology, University of Missouri Medical Center, Columbia, Missouri 65201. t Current address: 9500 Euclid Ave., Cleveland, Ohio 44106.

1 O'Conor, V. J.: Anastomosis of the vas deferens after purposeful division for sterility. J. Urol., 59: 229, 1948.

111

than optimal pregnancy rates achieved after deferens reanastomosis: 1) pre-vasectomy semen quality, 2) type of vasectomy, 3) fertility of mate, 4) sperm autoantibodies and 5) vas innervation. Did the patient have normal semen quality pre-vasectomy? Most vasectomies are performed on presumable fertile male subjects but a wide variety of semen quality falls within this group and this factor could decide post-vasovasostomy fertility. The technique of the vasectomy will 2 Schmidt, S. S.: Anastomosis of the vas deferens: experimental study. I. J. Urol., 75: 300, 1956. Dorsey, J. W.: Anastomosis of the vas deferens to correct post vasectomy sterility. J. Urol., 70: 515, 1953. 'Waller, J. I. and Turner, T. A.: Anastomosis of the vas after vasectomv. J. Urol., 88: 409, 1962. 5 Phadke, G. M. ·and Phadke, A.G.: Experiences in the re-anastomosis of the vas deferens. J. Urol., 97: 888, 1967 Shirley, S. W.: Panel discussion on Presented at twenty-ninth annual meeting of the can Fertility Society, San Francisco, California, April 3

6

5-7, 1973.

112

MONTIE AND STEW ART

TABLE

Reference

Dorsey 3

Waller and

1. Summary of series of uasouasostomy No. Pts. 6

10

Turner 4

Phadke and Phadke' Shirley'

76

Technique

Stent-silk worm gut Anastomosis-5-zero silk Stent-4F ureteral catheter Anastomosis-6-zero silk Stent-nylon

Sperm Postop. No.(%)

11

2. Results of canine studies on uasouasostomy

Preg-

Patent*

Obstructed

2 2

2 (50o/c) 2

3 3

2 (60%) 2

4 3

2

9

1 (90%)

nancy

Postop. No.(%)

5 (83)

3 (50)

6 (60)

1 (10)

63 (83)

42 (55)

15 (94)

-(60)

Anastomosis-6-zero

silk Stent-28 S.S. wire

TABLE

Anastomosis-6-zero dexon

Group I. No stent for vasovasostomy. 6-zero silk for anastomosis: 3 mos. 6mos. Group II. 3-zero dexont stent for vasovasostomy, 6-zero silk for anastomosis:

3mos. 6 mos. Group III. 3-zero chromic catgut stent for vasovasostomy. 6-zero silk for

anastomosis: 3mos. 6mos. Group IV. 3-zero chromic catgut stent

1 (70%)

for vasovasostomy, 6-zero chromic

catgut for anastomosis: 6mos. * Radiographic patency.

t Polyglycolic TABLE

acid synthetic absorbable suture.

3. Granuloma formation at anastomosis in canine

experiments l\o. Silk for anastomosis: No. procedures Vasa with significant granuloma formations

24 19

Chromic catgut for anastomosis:

No. procedures

10

Vas with significant granuloma formation

supply in vasectomy have also to be clarified 1s the possible lack of peristalsis of the vas deferens after reanastomosis may also contribute to infertility. 8 The aforementioned factors will have to be clearlv understood before we can predict and achieve ma;imum pregnancy rates post-vasovasostomy.

C FIG. 2. Vasovasostomy using absorbable intravasal stent. A, stent being inserted. B, stent in place, anastomosis being performed. C, anastomosis completed, stent in place.

be a significant factor in determining reversibility. A vasectomy with excision of a long segment of vas deferens or one at or near the convoluted portion of the vas deferens, may make later vasovasostomy technically impossible. The fertility status of the female partner will determine in some cases whether pregnancy can be achieved. In post-vasectomized male subjects there is about a 50 per cent incidence of sperm autoantibodies. 7 The exact role of these antibodies in subsequent fertility after vasovasostomy remains to be defined. The consequences of interrupting the sympathetic nervous 7 Ansbacher, R.: Vasectomy: sperm antibodies. Presented at twenty-ninth annual meeting of the American Fertility Society, San Francisco, California, April 5-7, 1973.

VASOVASOSTOMY OF THE FUTURE

A recent review of the results of vasovasostomv at the Cleveland Clinic revealed unsatisfactor~ results as determined by postoperative sperm appearance and postoperative pregnancies. A canine study was devised in an attempt to achieve consistently high anatomic patency rates with a technique that would eliminate the exteriorized intravasal stent, be easy to perform and not require special instruments or magnification. The exteriorized intravasal stent was considered to be undesirable because of the possibility of the stent being a portal of entry for infection, its inherent danger of being inadvertently removed prior to the 7 to 10 days required to assure epithelialization of the anastomosis and the possibility of sperm leakage at the site of vas perforation which could stimulate sperm autoantibody production. Because of these factors we have studied the feasibility of using absorbable intravasal stents in canine vasovasostomy. The entire series and results will be published in a separate communication. Figure 2 'Hulka, J. F. and Davis, J. E.: Vasectomy and reversible vasocclusion. Fertil. Steril., 23: 683, 1972.

VASOVASOSTOMY

illustrates the technique and tables 2 and 3 summarize the results. Our studies indicate that the use of absorbable suture material as an intravasal stent in vasovasostomy is feasible in dogs in which the vas deferens is comparable in size to that in man. Gross, microscopic and radiographic evaluation of the anastomotic area demonstrated that the intraluminal material was substantially absorbed with no significant reaction. One significant finding grossly and microscopically was the severe reaction in the wall of the vas deferens to the silk suture material 3 and 6 months postoperatively. This reaction would be more liable to produce obstruction and offers a greater chance for a proliferative epithelial reaction extending into the wall of the vas deferens. In contrast, granuloma formation was much less frequent and milder when chromic catgut was used for the anastomosis. Our findings suggest that chromic catgut is a more suitable suture material than silk for the anastomosis in vasovasostomy. SUMMARY

The number of vasectomies in the United States has increased significantly during the last several

113

years. Therefore, we can assume that we will be asked to reverse the vas occlusions more in the future. The success rate of vasovasostom:,· as determined by postoperative pregnancy rates has changed little during the last 25 years. surgical techniques have been used in an attempl to improve the success rate of vasovasostomy with little change in successful results. Multiple nontechnical aspects such as pre-vasectomy semen quality, fertility status of female partner and the role of sperm autoantibodies may be attributed to this continued low success rate, although to date little has been conclusive. Results of canine experiments using absorbahle intravasal stents are presented in which a 90 per cent radiographic patency rate was achieved. In addition, sperm granuloma formation was cantly less frequent and milder when chromic catgut was used for the anastomosis in contrast to the high rate of granuloma formation in vasa in which silk suture was used for vasovasostorny anastomosis.