The learning curve for endoscopic thyroidectomy: a single surgeon's experience

Endoscopic thyroidectomy has been known to surgeons for only 20 years. Related studies still are needed to make up for the deficiency of clinical experience. Research on the learning curve for the endoscopic thyroidectomy could be the method for investigating the operation experience. This retrospective study investigated 300 consecutive patients who underwent endoscopic thyroidectomy by a single endoscopist during the past 7 years. The study population was equally divided into 10 groups chronologically. Pearson's chi-square test and one-way analysis of variance were used to compare differences in the demographic data, operative time, operation score system, and follow-up data. The mean operative time was 98.07 min. The mean operation score was 6.00, and the rate of conversion to open surgery was 3.7%. There were no differences in demographic data or complications among the 10 groups. Subcutaneous edema occurred in five cases and transient recurrent laryngeal nerve palsy in five cases. There were significant differences in the mean operative time (p < 0.01) and the mean operation score (p < 0.01) among the 10 groups. Comparison of two neighboring groups showed differences in both operative time (p < 0.05) and operation score (p < 0.01) between groups 2 and 3 and in operation score between groups 5 and 6 (p < 0.05). The first 60 cases constitute the early stage of the learning curve for endoscopic thyroidectomy. The proficiency and stability of the operation reach the advanced level after 150 cases.