Learning Curve For Endoscope Holder In Endoscopic Thyroidectomy Via Complete Areola Approach

Objective:Observe the learning process of endoscope holder for endoscopic thyroidectomy via complete areola approach(ETCAA), study the characteristics of the learning curve for endoscope holder, and explore ways to shorten the learning curve for endoscope holder. Methods:From November 2012 to February 2014, 100 consecutive patients preoperatively diagnosed with bilateral benign thyroid tumor in the First Affiliated Hospital of Jinan University were enrolled in a clinical study. All the patients were divided into 10 consecutive groups chronologically, comprising 10 cases in each group. All the patients underwent ETCAA. Procedures were performed by the same surgeon assisted by the same endoscope holder. The surgeon was proficient in ETCAA with experiences of more than 500 cases, and the operative indications had been stable. The endoscope holder had never participated in ETCAA. Clinical data including demographic data, operative time, operative blood loss, conversion, postoperative complications, postoperative hospital stay, endoscope holding score, and interval of neighboring procedures were collected and analyzed. One-way classification analysis of variance(one-way classification ANOVA), Student-Newman-Keuls(SNK) test, and Pearson chi-square(χ2) test were used to analyze statistical significance for clinical data. The correlativity between the operative time and the case number, the endoscope holding score and the case number, the mean operative time and the mean interval of neighboring procedures, the mean endoscope holding score and the mean interval of neighboring procedures were analyzed with linear regression analysis. Results:1. All the patients underwent ETCAA successfully without conversion. The mean operative time was 96.30±13.10 minutes, the mean endoscope holding score was 74.65±14.08, and the mean interval of neighboring procedures was 4.50±3.48 days.2. There were significant differences among the mean operative time(P<0.0001) and the mean endoscope holding score(P<0.0001). There were no significant differences among the surgical methods(P=0.902), the mean operative blood loss(P=0.696), the mean postoperative hospital stay(P=0.658), and the mean interval of neighboring procedures(P=0.099).3. Multiple comparison revealed that the mean operative time of group 7, 8, 9, 10 were shorter than group 4, 5, 6, meanwhile the mean operative time of group 4, 5, 6 were shorter than group 1, 2, 3. Moreover, the mean endoscope holding score of group 7, 8, 9, 10 were higher than group 4, 5, 6, and the mean endoscope holding score of group 4, 5, 6 were higher than group 1, 2, 3.4. Linear regression analysis showed negative correlation between the operative time and the case number(r=-0.746, P<0.0001), positive correlation between the endoscope holding score and the case number(r=0.765, P<0.0001), positive correlation between the mean operative time and the mean interval of neighboring procedures(r=0.777, P=0.008), and negative correlation between the mean endoscope holding score and the mean interval of neighboring procedures(r=-0.809, P=0.005). Conclusion:1. A specific learning curve for endoscope holder in ETCAA does exist.2. The initial 30 cases composed the primary stage of the learning curve, and the endoscope holder could enter the intermediate stage of the learning curve after about 30 cases and expect a learning curve of approximately 60 cases in order to achieve the advanced stage.3. Properly increasing the operating frequency would help shorten the learning curve for endoscope holder.4. In order to enhance the quality of operation and the confidence of endoscope holder, it seems advisable for endoscope holder to select suitable cases according to the stage of learning curve.