Presentation Authors: Eiichiro Ohara*, Naoki Kawamorita, Sendai , Japan, Hideo Saito, Shigeto Ishidoya, Sendai, Japan, Yoichi Arai, Natori, Japan
Introduction: Post-operative urinary incontinence (PUI) is a common comorbidity following robot-assisted radical prostatectomy (RARP) or open radical prostatectomy (ORP). We previously reported a novel preoperative predictor, minimal residual membranous urethral length (mRUL), defined as the distance between the lower margins of the puboperinealis and bulbospongiosus muscles parallel with the urethra on preoperative magnetic resonance imaging (MRI). In the present study, we examined each parameter predicting postoperative recovery from PUI after RARP and ORP.
Methods: From 2007 to 2010 and from 2012 to 2016, a total of 111 and 198 patients were treated with ORP or RARP respectively at our institution. Patients underwent 3-T pelvic MRI for preoperative evaluation of prostate cancer. All patients completed the EPIC instrument before and at 1, 3, 6 and 12 months after surgery. Patients reporting "rarely or never" were defined as being continent. The MRI parameters mRUL and membranous urethral length (MUL) were measured and analyzed along with several other factors such as age, BMI, and nerve preservation.
Results: Median values for mRUL and MUL were 7.81 mm (IQR: 6.56 to 9.25) and 14.27 mm (IQR: 12.12 to 16.46) respectively in RARP patients. On the other hand, median values for mRUL and MUL were 7.15 mm (IQR: 6.18 to 8.24) and13.57 mm (IQR: 11.28 to 15.81) respectively in OPR patients. The recovery rates from PUI were similar for both groups. Multivariate analyses indicated that mRUL was a predictor of baseline continence, whereas MUL was a significant predictor of poor recovery from PUI (Table 1). When patients were classified using the median mRUL and MUL values, patients with both short mRUL and MUL group had significantly poorer recoveries from PUI after RARP and ORP (Fig.1).
Conclusions: The mRUL and MUL measured by preoperative MRI can predict poor recovery from PUI after radical prostatectomy. Therefore, health providers should provide patients with this important information prior to surgery.