Can Anatomical Measurements on Preoperative Pelvic Magnetic Resonance Imaging Predict Postoperative Urinary...

Background and Objective: Anatomical dimensions of the prostate and membranous urethra are well-established predictors of urinary incontinence following robotic prostatectomy. However, their role in predicting incontinence after holmium laser enucleation of the prostate (HoLEP) remains underexplored. This study aimed to evaluate the predictive value of preoperative anatomical measurements, including membranous urethral length (MUL), membranous urethral angle (MUA), levator ani thickness (LAT), and intravesical prostatic protrusion length (IPPL), in assessing the risk of early postoperative urinary incontinence following HoLEP. Methods: We retrospectively reviewed 122 patients who underwent HoLEP from April 2019 to June 2022 with preoperative MRI imaging. Anatomical features including coronal and sagittal MUL, MUA, LAT, and IPPL were assessed. Urinary incontinence, defined as the use of ≥1 pad per day, was evaluated at 1, 3, and 6 months postoperatively. All logistic regression analyses were adjusted for age, body mass index, postvoid residual, preoperative incontinence, and prostate-specific antigen, and receiver operating characteristic (ROC) curves were constructed to assess the discriminatory utility of MRI anatomical measurements. Results: Increasing MUL was significantly associated with reduced incontinence risk at 1 month (coronal MUL: odds ratio [OR], 0.85; 95% confidence interval [CI]: 0.75-0.96; p = 0.01; sagittal MUL: OR, 0.89; 95% CI: 0.79-0.99; p = 0.046). No significant associations were found for MUA, LAT, or IPPL. ROC analysis of averaged coronal and sagittal MUL revealed moderate discriminatory power (area under the curve: 0.644), with a threshold of 14 mm identified via the Youden index. Individuals with an MUL <14 mm were at nearly 4-fold increased odds of incontinence at 1 month (OR 3.835, 95% CI: 1.516-9.703, p = 0.005). Conclusions: Preoperative MUL measurement provides a practical, imaging-based method to predict early postoperative urinary incontinence following HoLEP. Incorporating MUL into preoperative evaluations may improve risk stratification, optimize patient counseling, and guide perioperative management strategies. Further prospective studies are needed to confirm these findings.