Applicability of perineal sonography in anatomical evaluation of bladder neck in women with and without genuine stress incontinence.

Thirty-seven patients with proven genuine stress incontinence (GSI) underwent ultrasound study to evaluate the bladder neck position relative to the symphysis pubis. Sixty-five continent women including 40 parous and 25 nulliparous women were recruited as a control group. Several parameters were found to be statistically different between incontinent and control groups (P < 0.01). If 28 degrees or 13 mm were used as the cut-off point for rotational angle (RA) and descent of bladder neck (DBN), the sensitivity, specificity, and positive and negative predictive values were 78.0%, 76.9%, 64.3%, and 33.3%, respectively. The specificity and positive predictive value for GSI increased to 83.1% and 67.6% if these two parameters were used together. Perineal sonography is valuable in assessing anatomic change of the bladder neck, but it is not a sensitive tool for predicting GSI.