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Abstract

We appreciate this thoughtful commentary and agree that estimated glomerular filtration rate (eGFR) does not represent a perfect metric to evaluate any clinical benefits attributable to integration of fluorescence-enhanced selective clamping into robotic partial nephrectomy. However, certain points should be considered before using this as a basis to conclude that the results presented here are without meaning. First, although our patient population does indeed display a wide range of postoperative eGFR and includes some with paradoxical eGFR increases (in both control and selective clamp cohorts), such a distribution is consistent with literature values from a number of prior large and multi-institutional studies. 1 Scoll B.J. Uzzo R.G. Chen D.Y. et al. Robot-assisted partial nephrectomy: a large single-institutional experience. Urology. 2010; 75: 1328-1334 Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar , 2 Patel M.N. Krane L.S. Bhandari A. et al. Robotic partial nephrectomy for renal tumors larger than 4 cm. Eur Urol. 2010; 57: 310-316 Abstract Full Text Full Text PDF PubMed Scopus (126) Google Scholar , 3 Kumar R.K. Sammon J.D. Kaczmarek B.F. et al. Robot-assisted partial nephrectomy in patients with baseline chronic kidney disease: a multi-institutional propensity score-matched analysis. Eur Urol. 2014; 65: 1205-1210 Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar Second, although eGFR is certainly sensitive to the multitude of factors identified by the commentators, these would need to have preferentially affected eGFR in 1 of the 2 groups for a detection bias to be introduced. In the absence of any such evidence, one would assume that eGFR variability affected both the control and selective clamp cohorts in a similar manner. Lastly, we agree that future analyses of this technique in the present and other populations would benefit by integrating degree of parenchyma sparing, as well as additional patient or tumor characteristics, outcome metrics, and longer follow-up. Such work could further delineate the contribution of minimized ischemia vs parenchymal volume sparing in ultimate renal function, while perhaps providing additional guidance on indications for this and other approaches to partial nephrectomy. In the interim, however, we believe that the results presented here serve as promising evidence of successful intraoperative minimization of ischemic kidney injury. Editorial CommentUrologyVol. 84Issue 2PreviewThe authors have published excellent results with the use of near-infrared imaging (NIRF) and selective clamp robotic partial nephrectomy. We use NIRF, as the authors do, to facilitate selective clamping and believe the technology to be highly predictable for renal perfusion. However, one may speculate that there may be an unrecognized error in the quantified renal functional benefits. Full-Text PDF