Microsurgical vasovasostomy.

Bilateral vasovasostomy was performed in 18 dogs and in 60 rats with Ethilon 10-0 and 11-0. The techniques used were: (a) a two-layer technique: the inner muscularis layer and the mucosal layer being sutured separately from the outer muscular layer; (b) a three-point one-layer technique: full-thickness stitches that traverse muscularis and mucosa at 120 degrees, 240 degrees and 360 degrees, between these three-point full-thickness stitches the muscularis layer is closed tightly. Patency of the vasal anastomosis was determined by injection of methylene blue and by vasography. Histologic and electron microscopic studies of specimens were performed at different intervals after the procedure. In a series of 25 rats, the results of the operation were determined by the biological fertility test: there was a 96% pregnancy rate.