LAUSR

PURPOSE Automated performance metrics (APMs) provide a novel approach to the assessment of surgical performance. Herein, we present a construct validation of APMs during robotic assisted partial nephrectomy (RAPN). MATERIALS AND METHODS APMs (instrument motion tracking/system events) and synchronized surgical videos from da Vinci Si systems during RAPN were recorded using a system data recorder. Each case was segmented into 7 steps: colon mobilization, ureteral identification/dissection, hilar dissection, exposure of tumor within Gerota's fascia, intraoperative US/tumor scoring, tumor excision, and renorrhaphy. APMs from each step were compared between expert (≥150 cases) and trainee (<150 cases) surgeons by Mann-Whitney U test (continuous variables) and Pearson's chi-squared test (categorical variables). Clinical outcomes were collected prospectively and correlated to APMs and R.E.N.A.L Nephrometry Score by Spearman's correlation coefficients (r). RESULTS A total of 50 RAPN cases were included for analysis, performed by 7 expert and 10 trainee surgeons. APM profiles significantly differed between experts and novices in the initial 5 steps (p <0.05). Specifically, experts exhibited faster dominant instrument movement and greater dominant instrument usage (bimanual dexterity) than trainees in select steps (p ≤0.045). APMs during tumor excision and renorrhaphy were significantly correlated with R.E.N.A.L. score (r ≥0.364; p ≤0.041). These included metrics related to instrument efficiency, task duration, and dominant instrument use. CONCLUSIONS Experts are more efficient and directed in their movement during RAPN. APMs during key steps correlate with objective measures of tumor complexity and may serve as predictors of clinical outcomes. These data help establish a standardized metric for surgeon assessment and training during RAPN.