Does Utilizing IRIS, a Segmented Three-dimensional Model, Increase Surgical Precision During Robotic Partial Nephrectomy?

Abstract

Preservation of renal parenchyma is a major goal when performing a partial nephrectomy. IRIS anatomical visualization software generates a segmented 3D model, allowing improved visualization of the tumor and surrounding structures. We hypothesize that using IRIS intraoperatively during partial nephrectomy on complex tumors increases the precision of surgical procedures and therefore may result in more tissue preservation. We identified 74 non-IRIS and 19 IRIS patients who underwent partial nephrectomy, with nephrometry scores of 9, 10, and 11. Propensity scores were used to match 18 pairs of patients on nephrometry score, age, and tumor volume. Pre- and postoperative imaging (MRI/CT) was obtained. Volumes of the preoperative tumor and preoperative whole kidney were obtained to calculate predicted postoperative whole kidney volume and then compared to actual postoperative whole kidney volume. Mean differences between predicted and actual postoperative whole kidney volumes were 19.2 cm³ (SD=20.2) and 32 cm³ (SD=16.1, <i>P</i> = .0074) for IRIS and non-IRIS groups, respectively. The mean improvement in precision for the IRIS procedure was 12.8 cm³ (95% confidence interval, 2.5 to Inf; <i>P</i> = .02). There was no significant change in mean glomerular filtration rate from baseline to 6 months postoperatively between IRIS and non-IRIS groups (-6.39, SD=15.8 vs -9.54, SD=13.3; <i>P</i> = .5). No significant differences in complication rates (0 vs 1, <i>P</i> = .2), worsening glomerular filtration rate staging (5 vs 4, <i>P</i> = 1), and >25% decrease in glomerular filtration rate (3 vs 4, <i>P</i> = 1) were found between IRIS and non-IRIS groups. We demonstrated that using IRIS intraoperatively when performing partial nephrectomy on complex tumors is associated with improved surgical precision.