Does the use of a small-diameter 22Fr resectoscope sheath reduce urethral stricture after transurethral resection of the prostate?

PURPOSE: Urethral stricture represents a significant late complication of transurethral resection of the prostate (TURP), leading to deterioration in urinary function and quality of life. This study aimed to compare the impact of 22Fr and 26Fr continuous-flow resectoscope sheaths on postoperative urethral stricture formation and perioperative outcomes. Methods: Patients who underwent bipolar TURP between 2021 and 2025 were retrospectively evaluated. Patients were divided according to sheath size into 22Fr (n = 135) and 26Fr (n = 145) groups. The primary endpoint was postoperative urethral stricture. A multivariable Cox proportional hazards model with Firth's penalized likelihood correction was used to identify independent predictors of stricture. Stricture-free survival was analyzed using Kaplan-Meier curves and compared with the log-rank test. RESULTS: Urethral stricture occurred in 5 patients (3.7%) in the 22Fr group and 22 patients (15.2%) in the 26Fr group (p = 0.0011). Operation time was shorter in the 26Fr group, while functional outcomes were comparable between groups. In multivariable Firth's penalized Cox regression analysis, use of a 26Fr sheath was the only independent predictor of urethral stricture (adjusted HR 4.08; 95% CI 1.16-14.37; p = 0.029). Kaplan-Meier analysis demonstrated a significantly higher cumulative incidence of urethral stricture in the 26Fr group (log-rank p = 0.003). CONCLUSIONS: Use of a 22Fr resectoscope sheath is associated with a significantly lower hazard of postoperative urethral stricture without compromising functional outcomes. Sheath diameter represents a clinically relevant and modifiable technical factor that may significantly influence long-term urethral morbidity after TURP.