Learning Curve Analysis of Transvaginal Natural Orifice Transluminal Endoscopic Surgery in Treating Ovarian Cysts: A Retrospective Cohort Study

Abstract

Background：Transvaginal Natural Orifice Transluminal Endoscopy (vNOTES) is regarded as a challenging surgical technique to learn but is promising in reducing perioperative pain and significantly improves the cosmetic outcomes. Previous studies on the learning curve analysis of vNOTES mainly focuses on the hysterectomy approach, while the vNOTES ovarian cystectomy’s learning curve was merely reported thought more frequently performed than vNOTES hysterectomy. Therefore, this study seeks to analyze the learning curve of three surgeons with varying levels of experience in performing endoscopic surgery for the treatment of ovarian cysts using vNOTES. Methods: A total of 127 patients with ovarian cysts of a variety of pathological types were treated by vNOTES ovarian cystectomy performed by three surgeons of different levels of endoscopic surgical experience. Each surgeon’s learning curve was plotted using the Cumulative Sum method and divided into three or four phases of technique learning at the turning point of the learning curve. The sociodemographic and clinical features of patients in each phase were then compared and factors potentially associated with operation time were also screened. Results: The learning curve was presented in four phases. The operation time (OT) was significantly shorter in phases II (53.66 ± 16.55 min) and IV (54.39 ± 23.45 min) as compared with phases I (68.74 ± 15.85) and III (75.93 ± 30.55) (p <0.001). More cases of serve pelvic adhesion and chocolate cyst were assigned in the later phases. The presence of pelvic adhesion [adjusted odds ratio (OR) 7.149 (0.506, 13.792), p = 0.035] and bilateral cyst [adjusted OR 16.996 (2.155, 31.837), p = 0.025], max diameter of cyst[adjusted OR 2.799 (0.174, 5.425), p = 0.037], and surgeon’s experience [adjusted OR -6.118 (-11.814, -0.423), p =0.035] were significantly associated with OT. Conclusion: There learning curve of ovarian vNOTES has four phases. vNOTES ovarian cystectomy could be mastered after performing seven, nine, and 16 cases by surgeons with the most, average, and least experience in gynecologic endoscopic surgeries. Trial registration: ChiCTR2200059282 (Registered on April 28th, 2022)