The factors of impacting on bladder neck descent in evaluation of female patients with stress urinary incontinence

Background: To explore the effects of bladder volume and intravesicalpressure on bladder neck descent (BND) in female patients with stress urinary incontinence (SUI), and to provide a base for standardization of evaluation for pelvic floor mobility in female SUI. Methods: The urodynamic data of 30 female patients diagnosed with SUI by sonography video urodynamic studies (SVUDS) at the Second Affiliated Hospital of Guilin Medical University and Shaoyang Central Hospital from January 2021 to January 2024 are retrospectively analyzed. The changes of pelvic floor mobility in female patients with SUI were observed by comparison of the differences of BND in female patients with SUI between different bladder volume (100 ml, 200 ml, 300 ml) with various various intravesical pressure (resting state, 60 cmH2O, 90 cmH2O). Results: In this study, the difference of the bladder neck descent (BND) was statistically significant (P<0.05)at different intravesical pressure with an identical bladder volume and the BND at 90cmH2O was greatest. In Valsalva state, the difference of BND was statistically significant(P<0.05)at various bladder volume with asame intravesical pressure, in which200ml of bladder volume could generate the most remarked BND compared to that of 100ml and 300ml(P<0.05). Conclusions: Higher of intravesical pressure was associated with more obvious BND of female patients with SUI. The effects of intravesical pressure on pelvic floor mobility is more obvious at 200ml of bladder volume compared to that of 100ml and 300ml. Therefore, beside intravesical pressure, bladder volume also was an important factor affecting pelvic floor mobility of female patients with SUI and 200mlof bladder volume should be recommended as the standard volume of bladder in evaluation of female SUI.