Long-term effects of vaginal dissection on the innervation of the striated urethral sphincter

Objective: To study the long-term effects of vaginal dissection on the innervation of the striated urethral sphincter. Methods: Perineal nerve terminal motor latency was measured before and 8 weeks and 1 year after anterior colporrhaphy, colpoperineoplasty, and vaginal hysterectomy in 33 women, 19 of whom also underwent endoscopic suspension of the bladder neck. Results: In the entire series, the mean perineal nerve terminal motor latency was prolonged before surgery over that in normal continent women and further prolonged 8 weeks and 1 year postoperatively. In the subjects who underwent vaginal hysterectomy and anterior colporrhaphy, perineal motor latencies were not significantly prolonged at the 8-week postoperative follow-up and had almost returned to preoperative values 1 year later. However, in those who underwent additional endoscopic bladder neck suspension, perineal motor latencies were prolonged at both postoperative follow-up examinations. Perineal motor latencies were unchanged 1 year postoperatively in continent patients (N = 19) but were prolonged in incontinent patients (N = 14). Conclusion: Vaginal dissection, especially during endoscopic bladder neck suspension, can worsen preexisting perineal neuropathy in patients with pelvic relaxation and stress incontinence.