Rethinking the value of sending vasectomy specimens for histologic examination: an analysis of arterial vasculature and failure to transect the vas deferens.

OBJECTIVES The testicular, deferential, and cremasteric arteries and their branches surround the vas deferens (VD), leaving them susceptible to injury during vasectomy. Literature describing the caliber of arteries seen in vasectomy specimens is lacking, making it difficult to categorize the significance of an observed artery. We aimed to establish reference values for arterial size typically encountered in vasectomy specimens and assess our institutional experience with failure to transect the VD. METHODS The luminal diameter of the largest artery in 231 consecutive VD specimens from 116 patients was measured microscopically. For comparison, the diameter of the largest artery within 10 spermatic cord cross-sections from inguinal orchiectomies was obtained. The immediate vasectomy failure rate based on histologic assessment was calculated using specimens from 2008 to 2012. RESULTS The luminal diameter of the largest artery encountered in a vasectomy specimen was 1.00 mm or less in 96.5% of cases. Artery sizes greater than or equal to 2.50 mm were only seen in spermatic cord resections. From 2008 to 2012, three (0.36%) of 837 patients undergoing vasectomy had specimens that showed failure to transect both VD. CONCLUSIONS Although the American Urologic Association and European Association of Urology state that histologic evaluation of vasectomy specimens is not required, we encourage the surgeon to send VD specimens for histologic examination. Doing so allows early identification of the failure to transect the VD and the resection of surrounding vasculature, providing quality control feedback to the surgeon.