High-Frequency Color Doppler Ultrasonographic Demonstration of Branch-Level Vascular Preservation and Peri-Graft Fluid After One-Sided Dorsal Onlay Urethroplasty

One-sided dorsal onlay urethroplasty (Kulkarni technique) aims to preserve urethral vascularity by limiting urethral mobilization to a single side of the corpus spongiosum while maintaining contralateral vascular attachments. Although the theoretical advantage of vascular preservation is widely accepted, direct postoperative visualization of perfusion at the branch level has rarely been demonstrated using non-invasive imaging. We present a single representative case of an 82-year-old male with a 54 mm anterior urethral stricture who underwent one-sided dorsal onlay urethroplasty. Representative postoperative images illustrating the vascular-preserving principle of this technique and its ultrasonographic assessment are shown. Postoperative evaluation was performed on postoperative day 4 using a high-frequency small-footprint linear probe (Hitachi L53K, ARIETTA ultrasound system), enabling high-resolution superficial imaging of the penile shaft. Color Doppler ultrasonography demonstrated preserved perfusion on the non-dissected side, including identifiable cavernous urethral shunt flow and distinct urethral and spongiosal arterial branches within the corpus spongiosum. In contrast, no detectable Doppler signals were observed on the dissected side, which may reflect reduced perfusion following surgical mobilization. In addition, peri-graft fluid collections were visualized as hypoechoic regions adjacent to the graft bed, which may represent expected early postoperative findings. These findings highlight the feasibility of bedside branch-level vascular and peri-graft assessment using high-frequency ultrasonography, suggesting its potential utility for early postoperative clinical interpretation after one-sided urethral reconstruction.