One-Sided Dorsal Onlay Urethroplasty With Penile Invagination (Kulkarni Urethroplasty) for Complex Anterior Urethral Strictures: A Single-Center Experience

Objectives: To evaluate surgical outcomes and patient-reported outcomes of one-sided dorsal onlay urethroplasty with penile invagination, so-called Kulkarni urethroplasty, in male patients with complex anterior urethral strictures, including pan-anterior and peno-bulbar urethral strictures. Methods: We retrospectively reviewed 39 consecutive male patients who underwent Kulkarni urethroplasty between 2016 and 2024. Through a perineal approach, one-sided urethral mobilization was performed with penile invagination to access the entire anterior urethra. Oral mucosa graft (OMG) or penile skin graft (PSG) was used as the urethral substitute. Success was defined as passing flexible cystoscopy without resistance and voiding without additional interventions. Patient-reported outcomes were assessed using the urethral stricture surgery patient-reported outcome measure (USS-PROM), Sexual Health Inventory for Men (SHIM), and EuroQol-5 dimensions (EQ-5D) questionnaires. Follow-up evaluations were conducted at 3, 6, and 12 months postoperatively and then annually. Results: The median stricture length was 44 mm (IQR 27-84). At a median follow-up of 12 months (IQR 6-34), the overall success rate was 89.7% (80.0% for OMG and 95.8% for PSG). Significant improvements were observed in maximum flow rate, post-void residual volume, lower urinary tract symptoms (LUTS) score, LUTS-related quality of life, EQ-5D score, and EQ-visual analog scale (all p < 0.001). SHIM scores remained unchanged, indicating preserved erectile function. Two (5.2%) experienced grade 2 donor-site complications. Conclusions: Kulkarni urethroplasty demonstrates excellent surgical outcomes and significant improvements in patient-reported outcomes for complex anterior urethral strictures while preserving erectile function. Both OMG and PSG appear to be viable options for this procedure.