Real-Time Ultrasound-Guided Transurethral Incision for Posterior Urethral Valves.

Background/

Objectives

Transurethral incision (TUI) is a common procedure for posterior urethral valves (PUV). However, no standardized method has been established to assess its efficacy intraoperatively. In this study, we aimed to develop and evaluate a real-time ultrasound-guided TUI (RUG-TUI) technique.

Methods

A single-center, retrospective feasibility study with a cohort design was conducted using historical controls to compare RUG-TUI with standard TUI in children with PUV. Data from patients who underwent RUG-TUI for PUV between April 2021 and July 2022 or TUI without real-time ultrasound guidance between August 2020 and March 2021 (control group) were retrospectively reviewed. A transperineal linear probe provided longitudinal imaging. The diameters of the constricted (C) and expanded (E) portions of the urethra before and after the procedure were measured, and the E/C ratio was calculated. The primary outcome was the duration of postoperative gross hematuria, and the secondary outcomes included changes in the urethral diameter ratio (E/C ratio), intraoperative complications, and residual obstruction on VCUG.

Results

The mean duration of post-procedure macroscopic hematuria was significantly shorter in the RUG-TUI group than in the control group (p = 0.049). No massive intraoperative bleeding or sphincter damage occurred. In the RUG-TUI group, the mean diameters of the constricted segment before and after the procedure were 3.0 (±1.0) and 5.7 (±1.2) mm, respectively, while the pre- and postoperative E/C ratios were 1.8 (±0.5) and 0.9 (±0.1), respectively (p < 0.0001).

Conclusions

RUG-TUI for PUV enabled visualization of the longitudinal axis of the urethra, allowing assessment of the anatomical relationship between the stenosis and external urethral sphincter. In this retrospective feasibility cohort, RUG-TUI was associated with a shorter duration of postoperative gross hematuria. These exploratory findings suggest that RUG-TUI may support intraoperative evaluation of procedural adequacy.