Assessment of the Male Urethral Reconstruction Learning Curve

Abstract

Objective: To evaluate the urethroplasty learning curve. Published success rates of urethral reconstruction for urethral stricture disease are high even though these procedures can be technically demanding. It is likely that success rates improve with time although a learning curve for urethral reconstruction has never been established.

Materials and methods: We retrospectively reviewed anterior urethroplasties from a prospectively maintained multi-institutional database. Success was analyzed at the 18-month mark in all patients and defined as freedom from secondary operation for stricture recurrence. A multivariate logistic regression was performed for outcomes vs time from fellowship and case number.

Results: A total of 613 consecutive cases from 6 surgeons were analyzed, with a functional success rate of 87.3%. The success rate for bulbar urethroplasties was higher than that for penile urethroplasties (88.2% vs 78.3%, P = .0116). The success rate of anastomotic repairs was higher than that for substitution repairs (95.0% vs 82.4%, P = .0001). There was a statistically significant trend toward improved outcomes with increasing number of cases (P = .0422), which was most pronounced with bulbar repairs. There was no statistical improvement in penile repairs over time. The case number to reach proficiency (>90% success) was approximately 100 cases for all types of reconstruction and 70 cases for bulbar urethroplasty. There were statistical differences in success rates among the participating surgeons (P = .0014). Complications decreased with time (P = .0053).

Conclusion: This study shows that success rates of anterior urethral reconstruction improve significantly with surgeon experience. Proficiency occurs after approximately 100 cases.

Figure 1

Figure dots represent the average recurrence rates by case volume (in blocks of 10 cases) of the 6 surgeons participating in the study. The vertical bars represent the recurrence rate range among study surgeons. Regression line and formula depicts calculated learning curve. The black arrow represents the number of cases required for the group to reach proficiency, defined as a success rate > 90%.

Figure 2

Figure dots represent the average recurrence rates of the 6 surgeons participating in the study by stricture location (bulbar in black; penile in grey). The average recurrence rate by location for each surgeon was determined by taking the bulbar and penile cases respectively from each overall block of 10 cases. These rates were then averaged between the 6 surgeons. The vertical bars represent the range of recurrence rates among study surgeons. Regression line and formula depicts calculated learning curve by location. The arrow represents the number of overall cases that the group required to reach proficiency for each location, defined as a success rate > 90% (note: no arrow is seen for penile repairs as a success rate of 90% was not achieved)

Figure 3

Figure dots represent the average recurrence rates by case volume (in blocks of 10 cases) of the 6 surgeons participating in the study by type of repair (EPA in black, substitution in gray). The average recurrence rate by type of repair for each surgeon was determined by taking the anastomotic and substitution cases respectively from each overall block of 10 cases. These rates were then averaged between the 6 surgeons. The vertical bars represent the range of success recurrence rates among study surgeons. Regression line and formula depicts calculated learning curve by type of repair. The arrow represents the number of overall cases that the group required to reached proficiency for each type of repair, defined as a success rate > 90% (note: no arrow is seen for anastomotic repairs as a success rate was > 90% starting with the first cases).