Learning Curve in Posterior Segment Ophthalmic Diagnostic Endoscopy: Implications for Budding Enthusiasts and Fellows-In-Training.

Purpose: To elucidate the learning curve for posterior segment diagnostic endoscopy (DE) based on the results of a self-trained (ST) and a supervised (SUP) vitreoretinal surgeon.

Methods: Retrospective review of medical records of DE performed between 2017 and 2023 by one ST and one SUP vitreoretinal surgeon at a tertiary eye care institute. Data were collected and the serial number of cases was plotted against the time taken for the procedure. A comparative regression plot was created for both the surgeons to know the slope of the learning curve. The start time was noted as that of attachment of the endoscope and the stop time was noted as the end of diagnostic evaluation. Procedures were divided into blocks of 10 cases each and the time taken for the procedures was calculated.

Results: Total of 106 eyes (58 by ST surgeon and 48 by SUP surgeon) were included. For ST surgeon, the time taken for the surgery correlated inversely (reduced sequentially) with the serial number of the case till the 20^th case (correlation coefficient = -0.5, p = .01), for SUP surgeon, the time taken for the surgery correlated inversely with the serial number of the case till the 10^th case (correlation coefficient = -0.9, p = <0.0001) and then stabilized. Neither of the groups had any adverse events.

Conclusion: About 20 cases for a self-trained and about 10 cases for a supervised vitreoretinal surgeon are required to get stable with DE. These observations have implications in creating a training module for DE with appropriate number of training cases.