WOFAPS 2025 8th World Congress of Pediatric Surgery

Shibo Zhu, Jinhua Hu, Yanqing Liu, Wei Jia

Guangzhou Women and Children's Medical Center,Guangzhou Medical University

​Objectives​​

This study sought to characterize the learning trajectory of two-stage Byars urethroplasty through retrospective analysis of complication rates and operative parameters across sequential cases; determine the procedural volume threshold required for technical proficiency, defined by stabilization of complications and operative efficiency; and develop evidence-based training frameworks to optimize resident competency in proximal hypospadias repair.

Methods​​

A single-surgeon retrospective study (2018–2022) included 113 patients undergoing two-stage Byars repair for proximal/complex hypospadias (74 penoscrotal, 39 perineal). Stage 1 (urethral plate mobilization and foreskin reconstruction) and Stage 2 (tubularized incised plate urethroplasty) were separated by a 6-month interval. Primary endpoints were complication rates (fistula, glans dehiscence, meatal stenosis, stricture) and operative times for both stages.

Learning curve analysis used cumulative sum (CUSUM) modeling to identify proficiency phases, with segmented regression comparing quartiles (Q1–Q4, 25–30 cases/group). Multivariate logistic regression adjusted for age, urethral plate quality, and chordee severity.

​Results​​
Median follow-up was 30 months (IQR 18–70). Complication rates demonstrated a statistically significant decrease across quartiles (Q1: 32% [8/25] vs Q4: 14.8% [4/27], p=0.02), driven by a 71% reduction in fistula incidence (Q1: 28% vs Q4: 8%, p<0.01). Mean operative time for Stage 2 decreased from 198±41 minutes (Q1) to 142±28 minutes (Q4) (p<0.01). CUSUM analysis identified competency acquisition at 60 cases (95% CI 55–63), with plateauing complication rates beyond this threshold. Subgroup analysis revealed no significant differences in outcomes between penoscrotal and perineal cohorts (p=0.41).

Conclusion​​
This study provides granular metrics for Byars urethroplasty training, advocating a competency-based progression model with supervised milestones up to Case 60. Incorporating these data into residency curricula could reduce early-career complication rates by 60% (as modeled in Q1→Q4 comparisons).