INTRODUCTION AND OBJECTIVES: Vasovasostomy most often requires anastomosis of two lumina with markedly discrepant diameters. We present a 4-layer microsurgical vasovasostomy technique that allows precise mucosal approximation and an atraumatic, leak-proof anastomosis.
METHODS: The testicular and abdominal ends of the vasa are transected using a slotted-never-cutting clamp and an ultra-sharp micro-knife to provide a perfect transverse cut. Prior to performing the anastomosis, the vasal ends are freshened by progressive trisection until healthy mucosa and muscularis with good blood supply are obtained. Minimal instrumentation of the mucosa is performed. The microdot-mapping technique is used by placing 6 evenly distributed microdots on the cut surface of the vas deferens, indicating the exit points of the mucosal sutures. This allows perfect approximation of very discrepant lumina. The mucosal layer employs inside-out placement of six 10-0 monofilament nylon sutures double-armed with 70 um diameter fishhook shaped tapered needles. The muscularis is approximated with 6 sutures of 9-0 nylon placed exactly in-between each pair of mucosal sutures. The vasal adventitia is approximated with 6 interrupted sutures of 9-0 nylon placed exactly in between each pair of muscularis sutures. The vasal sheath, the fourth layer, is approximated with 6 sutures of 7-0 PDS.
RESULTS: The average operating time per anastomosis was 2 hours. The outcomes of the surgery is 297 consecutive men with obstructive azoospermia revealed a patency rate (sperm count > 10,000/ml) at one year post-op of 99.7% (296/297), with a crude pregnancy rate of 55%. If couples with female-factor infertility were excluded, the pregnancy rate was 65%.
CONCLUSIONS: This multi-layer technique allows a precise, leak-proof approximation of vasa with markedly discrepant luminal diameters. Although a relative longer operating time and more meticulous techniques are required, close to 100% patency rates and high naturally conceived pregnancy rate are possible.