Free tunica vaginalis patch in urethroplasty. An experimental study.

The management of urethral strictures is a challenge for surgery. In the present study the value of tunica vaginalis tissue for urethroplasty was investigated. 30 male rabbits were divided into two groups. In group I (11 animals) a urethral defect was covered with a tunica vaginalis patch (n = 6) or was left uncovered (n = 5). In group II (19 animals) a preoperative urethral stricture was induced by electrocoagulation through a urethroscope. The strictured urethra was plastied with tunica vaginalis (n = 9) or preputial (n = 10) patches. The results were analyzed after a period of 2 weeks to 5 months with radiographic, macroscopic and microscopic methods. The tunica vaginalis graft showed its superiority over the preputial graft: only 1 postoperative short stricture from 15 plasties (6 normal and 9 strictured urethrae) was found in the plastied group, whereas 2 strictures from 10 plasties were seen in the preputial patch group. In the urethral defect group, strictures were seen in 2 of 5 animals. The mesenchymal tunica vaginalis epithelium was covered with thin transitiocellular-like epithelium resembling transitiocellular layers. The present study supports the earlier findings on the use of tunica vaginalis tissue in urethroplasty.