Multiple factors may cause de novo overactive bladder (OAB) after radical prostatectomy and the possible mechanisms include partial disruption of somatic and autonomic nerve arrangements due to bladder traction caudally during vesicourethral anastomosis¹; bladder tissue changes associated with inflammation, infection, or ischemia²; and a theory that urine outflow to the urethra induces detrusor overactivity. The mechanisms of advanced reconstruction of vesicourethral support (ARVUS) include directly supporting the urethra from the dorsal side similar to urethral sling procedures, reducing tension at the vesicourethral anastomosis, and restoring anatomical structures as similar to those under presurgical conditions³. We hypothesized that ARVUS would sharpen the posterior urethrovesical angle, thereby reducing urine outflow to the urethra and suppressing detrusor overactivity. In this study, we investigated the factors related to de novo OAB after robotic-assisted radical prostatectomy (RARP) and the impact of ARVUS.

A total of 799 patients underwent RARP at our institution during 2010–2023. After excluding patients who received preoperative hormone therapy or hormone therapy or radiation therapy within 1 year postsurgery and those with incomplete OABSS questionnaire data, we evaluated 559 patients. OAB was diagnosed when OABSS question 3 scored ≥2 points, and the total score was ≥3 points. De novo OAB was defined as the occurrence of OAB postoperatively in patients without preoperative OAB. We compared various factors (age, BMI, diabetes, hyperlipidemia, cT stage, preoperative IPSS, preoperative urethral length, preoperative levator thickness, prostate weight, ARVUS implementation, hood technique implementation, nerve-sparing approach, distance between the superior pubic edge and bladder neck, and posterior urethrovesical angle) between the non-OAB and de novo OAB groups at 1, 3, 6, 9, and 12 months postoperatively.

Of the 559 patients, 163 (29.2%) had preoperative OAB, and 396 patients (70.8%) had no preoperative OAB. The occurrence rates of de novo OAB were 49.4%, 31.9%, 26.4%, 17.9%, and 16.9% at 1, 3, 6, 9, and 12 months, respectively, postsurgery. Multivariate analysis revealed the nerve-sparing approach (1 m; p = 0.012, 3 m; p = 0.009) and preoperative urethral length (1 m; p = 0.008, 3 m; p = 0.019) as significant factors associated with de novo OAB occurrence at 1 and 3 months postsurgery, whereas no significant factors were identified at 6, 9, and 12 months. ARVUS implementation, distance between the superior pubic edge and bladder neck, and posterior urethrovesical angle showed no association.

De novo OAB was detected in approximately half of the patients at 1 month postsurgery and exhibited gradual improvement over time. In the multivariate analysis, ARVUS implementation was not identified as a significant factor for de novo OAB occurrence, whereas the nerve-sparing approach and preoperative urethral length were significant factors.

ARVUS implementation was not associated with de novo OAB occurrence. The nerve-sparing approach and preoperative urethral length may influence de novo OAB occurrence at 1 and 3 months postsurgery.

Bessede T, Sooriakumaran P, Takenaka A, et al: Neural supply of the male urethral sphincter: comprehensive anatomical review and implications for continence recovery after radical prostatectomy. World J Urol 35: 549-565, 2017
Porena M, Mearini E, Mearini L, et al: Voiding dysfunction after radical retropubic prostatectomy: more than external urethral sphincter deficiency. Eur Urol 52: 38-45, 2007
Student V, Vidlar A, Grepl M, et al: Advanced Reconstruction of Vesicourethral Support (ARVUS) during robot-assisted radical prostatectomy: One-year functional outcomes in a two group randomized controlled trial. Eur Urol 71: 822-830, 2017