Presentation Authors: Danielle Van Diepen, Lewis Chan*, Vincent Tse, Ruban Thanigasalam, Scott Leslie, Andre Lalak, Sydney, Australia
Introduction: Multiple studies have demonstrated that a shorter membranous urethral length (MUL) is associated with a higher risk of incontinence post radical prostatectomy (RP). Our previous functional imaging studies have demonstrated that transperineal ultrasound (TPUS) can be utilised to assess the male pelvic floor and urethra at rest and during physical activity. The aims of this study are to investigate changes in MUL at rest and during pelvic floor contraction (PFC) using TPUS and correlate with early continence 3 months post RP.
Methods: TPUS was performed in 105 men (mean age 64.2 years (range 45.7-78) as part of functional assessment prior to RP. 2D/3D ultrasound examinations were conducted using a Phillips EPIQ-7 ultrasound machine with C9-2 and X6-1 transducers to measure MUL at rest and during a PFC. Early continence outcome at 3 months post RP was assessed in 80 patients using the Expanded Prostate cancer Index Composite (EPIC) urinary domain questionnaire and correlated with pelvic floor imaging findings
Results: The membranous urethra was easily visualized on TPUS and MUL at rest was measurable in all patients with a mean length of 16.1 mm (range 8.7-23.1 mm). During a pelvic floor contraction, MUL was observed to increase in 99% of the patients to a mean length of 19.2 mm (range 11-28.3 mm) (p < 0.05). The mean increase in MUL was 3.3 mm (range -3.0-9.9 mm). The mean percentage increase in MUL from baseline was 21%. _x000D_
In patients with poor early continence (>2pads/day), there was a trend towards a smaller increase in MUL during a PFC both in absolute terms(p=0.057) and in percentage change from baseline(P =0.064). The mean change in MUL was 2.8 mm or 18% from baseline in patients using >2pads/day compared to a mean change in MUL of 3.6 mm or 25% from baseline in patients using < 2pads/day.
Conclusions: TPUS is a reliable method to measure MUL both at rest and during pelvic floor contractions. Using this method we showed that MUL significantly increases during a PFC. Patients with a smaller increase in MUL during PFC appear to have worse early continence outcomes post RP. TPUS may have a role in preoperative functional assessment of men undergoing RP.