The position of urethrovesical anastomosis after robotic radical prostatectomy assessed by MRI predicts early functional recovery: A cohort analyses from a randomized clinical trial

Abstract

Purpose: Functional and anatomical changes associated with prostate removal coincide with alterations in pelvic structures. Posterior rhabdosphincter reconstruction was designed to improve urinary continence after radical prostatectomy. The aim of this study was to determine magnetic resonance anatomic predictors of urinary recovery after radical prostatectomy, and to assess their relation to the type of reconstruction.

Material and methods: Forty patients were randomly selected from a trial (NCT03302169). Two independent radiologists determined the situation of the anastomosis in the pelvis according to MRI performed a month after the radical prostatectomy: vertical situation assessed as the distance to the line coccyx-inferior pubic margin (ACPv) and anteroposterior situation as the distance from the pubis (Distance A), and from the coccyx (Distance B).

Results: The Pearson correlation of ACPv, Distance A, and B between readers were 0.975, 0.940, and 0.711, p < 0.001. Patients with the reconstruction presented more cephalic situation of the anastomosis (higher ACPv) than patients with standard reconstruction technique. A multivariate analysis was performed including age, BMI, prostate volume, PRRS, and the MRI parameters. ACPv and Distance B were the only two independent predictors of no need for any urinary protection at 6 months after the surgery.

Conclusions: This is the first study that suggests positional differences according to the type of reconstruction after radical prostatectomy related to early urinary recovery. Magnetic resonance measurements to determine anastomosis positioning are reliable and have a strong correlation between readers. Anatomic MRI features are independent predictors of urinary recovery after robotic radical prostatectomy.

Keywords: Early continence; Magnetic resonance; Posterior rhabdosphincter reconstruction; Radical prostatectomy; Urinary incontinence.