Comparison of Perineal Sonographically Measured and Functional Urodynamic Urethral Length in Female Urinary Incontinence

Objectives. To detect the anatomical insufficiency of the urethra and to propose perineal ultrasound as a useful, noninvasive tool for the evaluation of incontinence, we compared the anatomical length of the urethra with the urodynamic functional urethral length. We also compared the urethral length between continent and incontinent females. Methods. 149 female patients were enrolled and divided into four groups (stress, urge, or mixed incontinence; control). Sonographically measured urethral length (SUL) and urodynamic functional urethral length (FUL) were analyzed statistically. Standardized and internationally validated incontinence questionnaire ICIQ-SF results were compared between each patient group. Results. Perineal SUL was significantly longer in incontinent compared to continent patients (p < 0.0001). Pairwise comparison of each incontinent type (stress, urge, or mixed incontinence) with the control group showed also a significant difference (p < 0.05). FUL was significantly shorter in incontinent patients than in the control group (p=0.0112). But pairwise comparison showed only a significant difference for the stress incontinence group compared with the control group (p = 0.0084) and not for the urge or mixed incontinent group. No clear correlation between SUL, FUL, and ICIQ-SF score was found. Conclusions. SUL measured by noninvasive perineal ultrasound is a suitable parameter in the assessment of female incontinence, since incontinent women show a significantly elongated urethra as a sign of tissue insufficiency, independent of the type of incontinence.