Delayed spontaneous recanalization of the vas deferens.

Eight patients were identified who had undergone successful vasectomy a mean of 4.6 years previously and in whom all were microscopically shown to have recurrent motile spermatozoa in their ejaculate. All had been referred following a pregnancy in their wives, and all agreed to undergo repeat vasectomy. Histological examination of the excised portions revealed the presence of spermatozoa in the distal end of one side; but also the presence of a well formed sperm granuloma in continuity with both divided ends of the vas. There does not appear to be any correlation with the suture previously used, nor incidence of infections or injury. Although recanalization is a recognized complication of vasectomy, the majority have occurred within months of the operation. The association of the delayed recanalization with sperm granuloma formation in these cases suggests an aetiological link, it being previously reported that such granuloma can develop up to six years postoperatively.