The number of sutures used depends on the situation and the anatomy found at surgery. This question first arose when some surgeons using low-power optical loops began claiming they were doing “microsurgery.” The use of only a few larger sutures was the tip-off, as microsurgery uses finer and more numerous sutures.
Most experienced surgeons currently performing microsurgical vasectomy reversal use a two-layer repair on the vas, suturing the inner mucosal layer separately from the outer muscular layer. But beware of “one size fits all” answers to the “number of sutures” question — it may suggest a surgeon with less experience.
The variability in the diameter of the vas, especially the inner lumen on the testicular side, is quite large from one patient to the next. The distal lumen (above the vasectomy) is almost always between 0.2 and 0.3 mm in diameter, while the proximal lumen (below the vasectomy, closer to the testes) may vary from 0.5 mm to 1.8 mm. To precisely align the inner channel the number of inner sutures needed will vary substantially, generally between 5 and 8 sutures. In Dr. Finnerty’s experience, using more sutures than this actually increases the risk of failure, as the delicate mucosa is shredded and frayed by too many stitches, promoting scarring.
Of course, the epididymal repair is technically quite different than a vas-to-vas repair, and generally requires fewer sutures on the mucosal layer than does the vas.