Epididymal extravasation following vasectomy as a cause for failure of vasectomy reversal.

Twenty-eight men undergoing vasectomy reversal who were found to have no sperm in the proximal vas fluid on one or both sides underwent microscopic epididymal exploration. In 33 of 39 cases so explored, normal sperm were found in the epididymal fluid of the corpus, despite absence of sperm in the vas fluid. Epididymal histology distal to this site revealed extensive interstitial sperm granulomas resulting from rupture of the epididymal duct. Testicular biopsy revealed normal spermatogenesis. Secondary epididymal obstructions were noted when there was copious fluid in the vas deferens proximal to the vasectomy site as well as when there was scanty fluid. It is concluded that persistent azoospermia after an accurate microscopic vasovasostomy results from the secondary epididymal obstruction induced by rupture of the epididymal duct related to the pressure increase after vasectomy.