Learning Curve for Transoral Endoscopic Thyroid Lobectomy

Objective: To define the learning curve for transoral endoscopic thyroidectomy via the vestibular approach (TOETVA). Study Design: Case series with planned data collection. Setting: Tertiary care academic hospital. Subjects and Methods: Included patients were those who met the 2015 American Thyroid Association guidelines for lobectomy and our group’s previously documented indications for TOETVA. Operative time (incision to closure) was used as a surrogate for procedural proficiency and plotted as a function of case number to determine a learning curve. A simple moving average of operative time was then calculated, with the proficiency case defined as the case number where the slope of this curve changed. Demographic/characteristic data, outcomes, and complications were compared between the skill acquisition period (case 1 to proficiency case) and the proficiency period (remaining cases). A linear regression model was then used to calculate and compare the slopes of the skill acquisition and proficiency periods in the “operative time versus case number” plot. Results: Thirty cases were attempted, with a procedural success rate of 29 of 30 (94%) and no incidence of permanent mental nerve or recurrent laryngeal nerve injury. The proficiency case was case 11. There was a statistically significant difference between the skill acquisition and proficiency periods in slopes of the linear regressions (–16.7 vs –0.3, respectively; P <.001) and median operative times (191 vs 119 minutes, P <.001). There was no difference in demographics, procedural success rate, or complication rate between the periods. Conclusions: The learning curve for TOETVA was 11 cases for the surgeon evaluated in this series.