[4] Learning curve of percutaneous renal access on a virtual reality simulator: Pilot study

Objectives: To assess the learning curve of percutaneous renal access (PCA) using the PERC Mentor™ simulator. Methods: Urology postgraduate trainees (PGTs) from postgraduate years (PGY) 4 and 5 were recruited. Participants received educational demonstration on how to perform the PCA using the ‘bull’s eye’ technique before being asked to perform task five on the PERC Mentor simulator, where they had to correctly puncture the middle calyx over a stone in a left kidney model. All participants were assessed objectively by the PERC Mentor simulator and subjectively by the validated Percutaneous Nephrolithotomy-Global Rating Scale (PCNL-GRS) tool. The learning curve of PCA was considered with plateauing in PCNL-GRS score, operative and fluoroscopy times, and absence of complications. Results: Four urology PGTs (three PGY-4 and one PGY-5), with median (range) age of 30 (27.8–32.3) years and without prior PCNL experience, participated in this study. Most of the participants were male (three of the four). Participants had previously performed a median of 100 cystoscopies, 50 TURBT, and 27.5 TURP prior to this study. The PGTs performed a total of 68 PCA procedures, with mean (SD) operative time of 159.8 (16) s, mean (SD) fluoroscopy time of 93.9 (11.3) s, mean (SD) number of attempts to puncture the pelvi-calyceal system (PCS) of 1.3 (0.1), mean (SD) PCS perforation of 0.68 (0.2), mean (SD) vascular injury of 0.3 (0.08), and mean (SD) PCNL-GRS score of 21.8 (0.6). Plateauing of the curve was achieved after 14 trials in terms of the PCNL-GRS score, the operative and fluoroscopy times, and PCS perforations. Conclusion: Based on these results, we think that a minimum of 15 PCA procedures are needed on the PERC Mentor to obtain the early part of the learning curve for PCA before starting practicing in the operating room