Outcomes of experimental rat varicocele with and without microsurgery.

Background: Experimental rat varicocele was usually developed by the conventional technique but with varied success; and microsurgical rat varicocele model was an effective alternative. In this study we further analyzed differential outcome of experimental rat model with and without microsurgery.

Methods: One hundred and twenty male Sprague-Dawley rats were randomly assigned to two groups. In Group A, experimental rat varicocele model was developed with conventional technique. The left renal vein was partially ligated with concurrent ligation of communicating branches between the left spermatic vein and common iliac vein. In Group B, all the above procedures were finished with microsurgical manipulation under operating microscope. Before and after model development, the mean diameter of the left internal spermatic vein was compared; and at 8 weeks after initial surgery the mean sperm concentration and motility in both groups was analyzed.

Results: The baseline mean diameter of the left internal spermatic vein in Group A and Group B was 0.14 ± 0.04 and 0.15 ± 0.03 mm, respectively (P =0.3157). In Group A 9 rats had severe complications resulting in model failure; while in Group B all rats had successful model except for one died of anesthetic accident (P = 0.008). At 8 weeks after initial surgery the mean left internal spermatic vein, sperm concentration and motility in both groups was 1.65 mm, 321.5 × 10(6)/gm and 51.9%; and 1.65 mm, 318.9 × 10(6)/gm and 53.5% respectively. There was nonsignificant difference of internal spermatic vein diameter, sperm concentration and motility between two groups.

Conclusions: Microsurgery makes developing experiment rat varicocele model easy. Compared with conventional technique, microsurgical rat varicocele model has higher success rate and less complication.