Session: MP78: Trauma/Reconstruction/Diversion: Urethral Reconstruction (including Stricture & Diverticulum) II
MP78-13: Predictive Value of Membranous Urethral Length on Magnetic Resonance Imaging for Continence after Delayed Anastomotic Urethroplasty for Male Pelvic Fracture Urethral Injury
Introduction: The literature suggests that male pelvic fracture urethral injury (PFUI) occurs most commonly at the bulbo-membranous junction and the external sphincter function is preserved to some extent. Magnetic resonance imaging (MRI) enabled the most accurate assessment of post-traumatic anatomy. We evaluated the residual membranous urethral length (MUL) on MRI and investigated its impact on post-urethroplasty continence. Methods: Of the 230 male patients with PFUI evaluated by urethrography, cystourethroscopy, and pelvic MRI, who underwent delayed anastomotic urethroplasty between 2008 and 2022, 104 who had no recurrent stenosis on cystoscopy and underwent a 1-hour pad test 1 year after urethroplasty, were retrospectively reviewed. MUL was defined as the distance between the distal end of the proximal urethral stump and the prostatic apex, measured on T2-weighted MRI images (Figure 1). MRI findings including the MUL were reviewed by two expert radiologists, blinded to the clinical data. A patient was declared as having post-urethroplasty incontinence (PUI) when their 1-hour pad test was greater than 2 g. Results: Thirty-six (34 .6%) patients were diagnosed with PUI. The median volume of the 1-hour pad test was 1.0 g (interquartile range, IQR 0–4.75). All patients had a measurable MUL on MRI (Figure 1), and the median MUL was 8.1 mm (IQR 5.2-10.8). PUI was not associated with the patient’s age, body mass index, a history of urethroplasty, or the type of urethroplasty (simple perineal or elaborate approach). However, an open bladder neck on antegrade cystoscopy and/or cystourethrography (OR 11.85, 95% CI 2.23-62.9, p = 0.004) and a longer MUL (every extra millimeter, OR 0.87, 95% CI 0.76-1.00, p = 0.04) were significant predictors of PUI on multivariate analysis. Conclusions: A greater preoperative MUL is significantly and positively associated with PUI in male patients with PFUI. MUL on MRI may be potentially valuable to reconstructive urologists when counseling patients in clinical practice, prior to urethroplasty. SOURCE OF Funding: none
