Learning curve of various type of male urethroplasty

Abstract

Purpose: To determine the number of cases required to achieve a specified recurrence-free rate (>80%) among urethroplasty types.

Materials and methods: A retrospective analysis of consecutive patients, who underwent urethroplasty performed by a single surgeon between April 2013 and January 2019, was conducted. Urethroplasty subtypes were divided according to stricture location: penile, bulbar, and posterior. If there was no recurrence for >6 months after surgery, the surgery was considered to be a success. The average success rates among quintile groups were compared to determine the learning curve for each type.

Results: Of 150 patients who underwent urethroplasty, 112 were included in this study. The overall success rate was 89.7% in penile, 97.8% in bulbar, and 74.1% in posterior urethroplasty. Bulbar urethroplasty reached the target success rate in the first quintile group (1-9 cases). Penile urethroplasty also achieved the target success rate in the first quintile group (1-8 cases), and the success rate gradually increased until the fifth quintile group (32-39 cases). In posterior urethroplasty, the target success rate was achieved in the fifth quintile group (20-27 cases).

Conclusions: Bulbar urethroplasty had the fastest learning curve, and posterior urethroplasty the slowest.

Keywords: Learning curve; Reconstructive surgical procedures; Urethral stricture.

Fig. 1. The success rate of each urethroplasty subtype. In all three groups, the success rate increased as the number of cases increased. Bulbar urethroplasty had the fastest learning curve, while posterior urethroplasty was the slowest.

Fig. 2. Operation time for each urethroplasty subtype. In all three groups, the mean operation time decreased as the number of cases increased.

Fig. 3. Estimated blood loss (EBL) for each urethroplasty subtype. Patients in the posterior urethroplasty group had the highest EBL, which gradually decreased after the third quantile (12–18 cases).