Perineal ultrasound to assess the urethral spatial movement in stress urinary incontinence in women

BACKGROUND: Perineal ultrasound as a non-invasive method for the diagnosis of female stress urinary incontinence has attracted more and more attention. However, the criteria for stress urinary incontinence in women using perineal ultrasound have not been fully established. Our study aimed to evaluate characteristics of the urethral spatial movement with perineal ultrasonography. METHODS: A total of 136 female patients with stress urinary incontinence and 44 controls were enrolled. Stress urinary incontinence was diagnosed using the International Consultation on Incontinence Questionnaire Short Form, medical history and physical examination, and severity was assessed using a 1 h pad test. We described the mobility of four equidistant points (A–D) located along the urethra length. The retrovesical and urethral rotation angles were measured using perineal ultrasonography at rest and during the maximal Valsalva maneuver. RESULTS: Patients with stress urinary incontinence showed a more significant vertical movement at Points A, B and C than controls. The mean variations in the retrovesical angle were significantly larger in patients with stress urinary incontinence at rest and during the Valsalva maneuver than in controls (21.0 ± 16.5° vs. 14.7 ± 20.1°, respectively). The cut-off value for the retrovesical angle variation was 10.7° with 72% sensitivity and 54% specificity. There was a receiver-operating characteristic curve area of 0.73 and 0.72 for Points A and B, respectively. A cut-off of 10.8 mm, and 9.4 mm provided 71% sensitivity and 68% specificity and 67% sensitivity and 75% specificity, respectively. CONCLUSIONS: The spatial movement of the bladder neck and proximal urethra, and variations in the retrovesical angle may be correlated with clinical symptoms and facilitate to the assessment of SUI.