Tissue Adhesive Vasal Anastomosis Compared to Conventional Sutured and Contact Neodymium: Yttrium Aluminum Garnet(Nd:YAG) Laser Vasovasostomy in Rats

Shin, Myung Sik; Lee, Dong Han; Lee, Seung Ju; Cho, Su Yeon; Cho, Yong Hyun; Yoon, Moon Soo; Kim, Young Sill

Abstract

PURPOSE: Conventional suture anastomosis using fine non-absorbable suture material is the most commonly used vasovasostomy procedure. But it needs experienced microsurgical skills and prolonged operative time and sometimes it causes local injury to the vas to prevent healing of anastomosis. Recent advances of tissue-welding laser technology in vasovasostomy have resulted in reduced requirement of microsurgical skills, less trauma of anastomotic site and less operative time. Its pitfalls are, however, the difficulty in transfering equal laser energy to anastomotic site and weakness in tensile strength of anastomosis. We conducted this study to determine whether a tissue adhesive which is widely used in clinical field recently could solve the problems of the conventional suture anastomosis and laser technology as mentioned above. MATERIALS AND METHODS: 42 male Sprague-Dawley rats initially underwent midline scrotal exploration and transection of their vas deferens bilaterally followed by immediate microsurgical vasovasostomy by one of the three experimental methods. All groups initially had the vas ends coapted by two full layered sutured sutures of 10-0 nylon under an operating microscope. The conventionally sutured group had an additional four to six 10-0 nylon sutures. The Nd:YAG laser-assisted group underwent laser welding with denaturation of the serosa to seal the anastomosis. A fibrin glue was placed topically over the coapted vas ends in tissue adhesive group. RESULTS: 1. There were statistically significant differences in operative time among the conventionally sutured (31.5 minutes) group, the laser-assisted (19.4 minutes) group and the tissue adhesive group (14.4 minutes)(p<0.05). 2. The patency rates of the anastomosed vas were 75.0%, 84.6%, and 89.3% respectively in the conventionally sutured group, the laser-assisted group and the tissue adhesive group. Although the patency rate was highest in the tissue adhesive group, it was not statistically significant (p>0.05). 3. The patency degree of the vas, measured by the flow rate of saline, was 1.40 ml/min, 1.76 ml/min, and 2.17 ml/min respectively in the conventionally sutured group, the laser-assisted group and the tissue adhesive group and there was statistically significant difference between the conventionally sutured group and the tissue adhesive group(p<0.05). 4. The tensile strength of the anastomosed vas was 112.9 g, 100.2 g, and 124.8 g respectly in the conventionally sutured group, the laser-assisted group and the tissue adhesive group and there was statistically significant difference between the laser-assisted group and the tissue adhesive group(p<0.05). 5. Histological findings showed relatively thick fibrotic scar on the anastomotic plain of the conventional suture group and limited scar formation on that of the laser-assisted group and the tissue adhesive group. CONCLUSIONS: These results demonstrate that vasovasostomy using fibrin glue tissue adhesive does not need expert microsurgical skill, requires less operative time and would give more favorable postoperative results than conventionally sutured or laser-assisted vasovasostomy.