AB148. Study on different microsurgical anastomosis in the treatment of rat model with obstructive azoospermia

OBJECTIVE: To study the method of making of obstructive azoospermia (OA) animal model, and compare the advantages and disadvantages of different microsurgical anastomosis. METHODS: We randomized 20, 6-week-old male SD rats into five groups, including the sham operation, the control, the standard double-armed longitudinal intussusception vasoepididymostomy (VE), the single-armed and reverse single-armed longitudinal intussusception vasoepididymostomy groups. Bilateral vasectomy (closed epididymis) was performed in all rats to make OA animal model except those in the sham operation group. Two weeks after vasectomy, bilateral standard double-armed longitudinal intussusception VE, single-armed and reverse single-armed longitudinal intussusception VE was performed in the assigned rats. Rats in the control group underwent vasectomy only. In the sham operation group the testes were moved out of the scrotum and then returned. Rats were sacrificed after 12 weeks. The anastomosis and vasectomy sites were inspected for sperm granuloma. Patency was confirmed by injecting Methylene blue from the abdominal end of the vas through the anastomoses to epididymis. RESULTS: In the standard double-armed longitudinal intussusception VE, the single-armed and reverse single-armed longitudinal intussusception VE groups the patency rate was 100%, 75%, 87.5%, sperm granuloma rate was 12.5%, 25%, 25%, the average operation time was 38.1±4.3, 42.3±2.9, 41.0±3.3 min. CONCLUSIONS: Bilateral vasectomy (closed epididymis) is reliable, simple method to make OA animal model for performing microscopic VE training. The results of our study have shown that the single-armed suture technique to perform VE is almost as effective as the double-armed technique and can save operation cost. This allows the use of single-armed sutures to perform microsurgical VE, in which double-armed sutures are not available. Reverse single-armed longitudinal intussusception VE can reduce the probability of back-walling the tubular lumen.