Correlation between Bladder Neck Mobility and Voiding Phase Urodynamic Parameters in Female Patients with Stress Urinary Incontinence.

OBJECTIVE: The correlation between bladder neck mobility (BNM) and voiding function in females has not been examined before. This study investigated the correlation between BNM and voiding phase urodynamic parameters in female patients with stress urinary incontinence (SUI).

METHODS: We recruited female patients with SUI between January 2005 and 2010. All patients underwent video urodynamic study (VUDS) including measurement of the bladder neck descent using the Valsalva maneuver and leak point pressure. BNM was defined as maximal bladder neck descent under Valsalva maneuver. The correlation between BNM and urodynamic parameters was analyzed with Spearman correlation.

RESULTS: A total of 158 patients were enrolled in the study. The mean age of the patients was 56.5 ± 10.4 years (range: 27-83). BNM was significantly correlated with mean flow rate. Using the cutoff value of 60 cmH2O for valsalva leak point pressure (VLPP), the patients were classified into intrinsic sphincter deficiency (ISD) and non-ISD. In ISD patients (n = 74), BNM was significantly correlated with maximal and mean flow rate. In non-ISD patients, there was no significant correlation between BNM and urodynamic parameters. Detrusor pressure on voiding was significantly lower in ISD patients compared with non-ISD.

CONCLUSIONS: In ISD patients, we found a positive correlation between BNM and flow rates. This is the first study to identify a close association between bladder neck mobility and voiding function in female SUI patients. Future studies are required to clarify the mechanism and to determine the significance of this finding.