[Surgical treatment of female stress urinary incontinence. Determination of the location of the vesico-urethral junction].

The accuracy of the various methods used to locate the vesico-urethral junction was evaluated in 20 female patients. In each patient the following parameters were successively measured: functional length of the urethra (urethral profile); distance from the meatus to the posterior lip of the vesical cervix (endoscopy), length of the catheter segment between the balloon and the meatus. Finally, the location of the balloon was determined intra-operatively and compared with the "urethroscopic" findings. The results obtained showed that locating the vesico-urethral junction solely from the location of the balloon could be misleading and that there was a significant difference (nearly 8 mm) between functional and urethroscopic measurements. These results led to a mathematical formula which enables the anatomical length of the urethra to be measured from its functional length. The authors suggest that this length, measured with an urethrometer, should be used for precise location of the junction during surgery for female stress incontinence.