To investigate the application value of MRI in evaluating the disorders of pelvic floor in female stress urinary incontinence (SUI).

From January 2017 to January 2019, the patients in the SUI group and the control group of Beijing Chaoyang Hospital, Capital Medical University were prospectively collected. Some patients in the SUI group were treated with tension-free vaginal tape (TVT). The dynamic MR was performed in both SUI patients and volunteers, and the following functional MR parameters were assessed between two groups: the urethral length and urethral hypermobility; the opening of urethral and bladder neck; and the pelvic organ prolapse. For SUI patients, the functional changes of the pelvic floor on MRI after TVT was also analyzed. Chi-square test, rank-sum test and t test were used.

Comparing with the control groups (n=25), the urethral hypermobility, shortening functional urethral length, bladder neck funneling and urethra opening were significantly associated with SUI group (n=33). Thirty one patients were treated with TVT, 12 of them were reexamined with MRI at 3 to 6 months after operation. Postoperative MR showed that SUI patients had lower risk of the urethral opening and bladder neck funneling (P<0.05). There were significant differences in the length of functional urethra, angle of urethra movement, H-line, M-line, bladder funnel sign, urethra opening and bladder prolapse between the two groups (P<0.05). There was a significant difference between the bladder funnel sign and urethra open sign before and after TVT (P<0.05). There was no significant difference in the degree of bladder prolapse and uterus prolapse, length of urethra and angle of urethra movement between the two groups (P>0.05).

MRI can accurately evaluate pelvic floor function of SUI patients. However, TVT did not significantly improve weak pelvic supporting structures and pelvic organ prolapse.

Urinary incontinence, stress; Magnetic resonance imaging; Tension-free vaginal tape; Pelvic floor disfunction; Pelvic floor