Transperineal Ultrasound Measurement of Retrovesical Angle at Rest for Assessing Severity of Stress Urinary...

Background/Objectives: The aim of this diagnostic accuracy study was to evaluate the usefulness of transperineal ultrasound parameters of urethral instability for assessing the severity of stress urinary incontinence (SUI) in women and their relationship with health-related quality of life (HRQOL). Methods: This cross-sectional study included 240 women with symptomatic SUI (mean age 41 years). Severity was classified using the Sandvik Severity Index (reference standard). Transperineal ultrasound (index test) was performed to measure the retrovesical angle (RVA) at rest and during Valsalva manoeuvre, bladder neck descent (BND), and urethral rotation angle (URA). Impact on HRQOL was assessed with the ICIQ-SF and King's Health Questionnaire (KHQ). Operators were blinded to clinical data and vice versa. Results: The RVA at rest showed the best discriminatory capacity for identifying severe/very severe SUI (AUC 0.83, 95% CI 0.77-0.89; sensitivity 71%, specificity 84%), with an optimal cut-off value of 118.1° (adjusted for age, BMI and miscarriage). RVA values increased progressively with SUI severity both at rest and during Valsalva (p < 0.001). Significant positive correlations were found between RVA and ICIQ-SF scores (ρ² = 0.412 at rest, p < 0.001). In contrast, URA remained within normal limits (<20°) and did not differ across severity groups. Conclusions: Transperineal ultrasound measurement of the RVA at rest is a reliable, non-invasive parameter for grading SUI severity and correlates with its impact on HRQOL. These findings suggest that RVA at rest has good discriminatory capacity for identifying women with severe or very severe SUI and may have potential as an adjunct to clinical assessment. However, given the moderate sensitivity observed and the lack of data on management outcomes, prospective studies are needed to determine its utility in guiding referral or treatment decisions.