Effect of level of anastomosis and quality of intraepididymal sperm on the outcome of end-to-side epididymovasostomy

Objectives. Epididymovasostomy is commonly performed at the most distal site of the epididymis where whole sperm are present within the lumen, regardless of their motility status. Although more fresh and motile sperm can be found more proximally within the epididymis, it is believed that the outcome of epididymovasostomy is better more distally. Because the current results of epididymovasostomy are far from perfect, it would be ideal to be able to harvest motile sperm for cryopreservation at the time of surgery in case the patient remains azoospermic postoperatively. The objective of this study was to determine the effect of the level of epididymal anastomosis and duality of sperm on the outcome of surgery. Methods. An end-to-side epididymovasostomy was performed on 131 azoospermic men with a mean age of 39 years and a mean obstructive interval of 18 years. The etiology of obstruction was vasectomy in 48%, infectious in 19%, congenital in 20%, and unknown in 13%. The average duration of follow-up was 32 months. The overall patency rate was 67% and pregnancy rate was 27%. Subgroups of patients with an anastomosis to the same level of the epididymis on all functional sides were identified as follows: caput (56), corpus (28), and cauda (13). These groups were compared in regard to the presence of motile sperm within the epididymal lumen at the time of surgery, patency rates, postoperative semen quality, and pregnancy rates. Results. Motile sperm were present more often in both the caput (54%) and corpus (61%)than in the cauda epididymis (25%) (P < 0.05). The patency rates for the three subgroups were not significantly different. The postoperative total motile sperm count and pregnancy rate for the corpus epididymis (13 x 10(6) and 45%) was significantly (P < 0.05) better than for the caput (4.4 x 10(6) and 22%) but no different than that of the cauda (10 x 10(6) and 25%). The patency and pregnancy rates for anastomoses performed at levels demonstrating motile sperm were not significantly better than at sites with nonmotile sperm, but the postoperative total motile sperm count was better (P < 0.05). Conclusions. The results of this study suggest that the outcomes of epididymovasostomy to the corpus and cauda epididymis are roughly equivalent and superior to the caput. Therefore, it may be reasonable to move more proximally from the cauda to corpus in the search for motile sperm for cryopreservation during an end-to-side epididymovasostomy. In contrast, moving from the corpus to the caput epididymis has a significant adverse effect upon outcome; it is, therefore, not worthwhile to search for viable sperm for cryopreservation in this clinical setting. (C) 1997, Elsevier Science Inc.