Comparison of standardized pre- and postoperative functional pelvic cine-MRI in patients with a bulbourethral composite suspension due to post-prostatectomy incontinence

Abstract

To compare functional pelvic cine-MRI in patients with post-prostatectomy incontinence before and after implantation of a bulbourethral composite suspension. Functional pelvic 1.5 T cine-MRI was performed at rest, under standardized Valsalva pressure and during micturition in six patients with post-prostatectomy incontinence before and 3 months after a bulbourethral composite suspension. Visibility and positioning of the implant as well as membranous urethral length (MUL) and positioning of the bladder neck (BN) in comparison with the pubococcygeal line (PCL) were evaluated. Clinical outcome was measured by patient-reported pad use and standardized questionnaires (ICIQ-UI SF and I-QOL). Paired data were tested with a Wilcoxon signed-ranks test. Surgery was successfully performed in all patients. All patients returned to complete voiding. The ICIQ-UI SF score decreased significantly from median 16.5 to 5 (p = 0.016). I-QOL increased significantly from 70.5 to 93.5 (p = 0.047). Pad use improved from median 2 pads to 0 pads postoperatively (p = 0.031). Four of six patients were completely pad-free, and 2 were failures with persisting urinary incontinence. MRI revealed significant differences of the MUL at rest with median of 8 mm pre- and 13 mm postoperatively (p = 0.016). BN showed a significant elevation with respect to PCL under Valsalva with in median 0.5 to 5 mm postoperatively (p = 0.016). No significant MRI differences were found between patients showing clinical success or failure. The bulbourethral composite suspension was associated with an increase in urethral length, urethral coaptation zone and bladder neck elevation, implying a non-compressive mode of action.