A modified technique of two-layer microsurgical vasovasostomy is described which permits continuous inspection of the lumen. A stricture-free anastomosis was documented in experimental animals by mating and scanning electron microscopic studies. The success of this procedure is attributed to precise placement of fine mucosal sutures, minimal fibrosis, and a fluid-tight anastomosis.
PIP: 25 Sprague-Daveley rats had bilateral division of the vas deferens with immediate microsurgical anastomosis. The 2-layer microsurgical vasovasostomy as described in detail tin this report permits continuous imspection of the lumen. To determine the efficacy of this procedure, all the animals were mated and the anastomotic sites studied by scanning electron microscopy (EM) 2 to 4 months after surgery. Overall pregnancy rate was 50%. Early failure in the series was attributed to technical ineptitude and failure to appreciate the importance of a blood-free field. The last 10 animals had a pregnancy rate of 80%. Scanning EM showed near total, bilateral occlusion in the sterile rats, as contrasted to the widely patent lumen of animals with documented fertility. By 2 months, the luminal sutures were covered by regenerating mucosa. Fibrosis was observed in areas immediately surrounding mucosal and muscular sutures. Precisely placed mucosal sutures which evert the mucosa and decrease stenosis are critical to a stricture-free anastomosis. Expert handing of fine sutures, small needles and delicate microsurgical instruments accounted for lack of fibrosis after vasovasostomy was performed.