Surgical Navigation Improves Renal Parenchyma Volume Preservation in Robot-Assisted Partial Nephrectomy: A Propensity Score-matched Comparative Analysis.
To investigate the relationship between the surgical-navigation (SN) system and postoperative parenchyma preservation volume and assess the feasibility of image-guided surgery in robot-assisted partial nephrectomy (RAPN).We developed SN with registration between real-time endoscopic images using three-dimensional virtual reality models for RAPN. Surgical outcomes of 44 (non-SN group) and 102 patients (SN group) between June 2013 and December 2018 were retrospectively analyzed. To adjust for potential baseline confounders, propensity score matching (1:1) was performed. Renal parenchymal preservation rate and extra parenchymal volume with a tumor including functional and oncological outcomes (“trifecta” defined as warm ischemic time of <25 min, no complications, and negative surgical margins; “pentafecta” defined as >90% preservation of estimated glomerular filtration rate at 12 months postoperatively and chronic kidney disease upstaging) were evaluated using volumetric analysis and compared.After matching, 42 patients were allocated to each group. No significant differences in baseline characteristics; complications; and intraoperative, trifecta, and pentafecta outcomes were observed between the two groups. Pathological T-stages were significantly different between the two groups (T1a/T1b/T2a or more: 25/10/7 in the non-SN group vs. 35/7/0 in the SN group, P=0.003). Extra parenchymal volumes and parenchyma volume preservation rate were significantly higher in the SN group (21.4 vs. 17.2 mL, P = 0.041 and 83.5% vs. 90.0%, P = 0.042, respectively). SN was positively associated with improved parenchyma preservation volume (P = 0.003).SN preserves renal parenchyma in RAPN and may contribute to improvement in postoperative renal function.