The significance of predictable traumatic area by renorrhaphy in the prediction of postoperative ipsilateral renal function

To determine the relationship between the actual renal function loss and volume loss in robot-assisted partial nephrectomy (RAPN) using a novel three-dimensional volume analyzer.

We respectively evaluated the medical records of 23 consecutive patients who underwent RAPN between January 2012 and March 2016 and the data on their kidney function and parenchymal mass specific to the operated kidney. Parenchymal volume was measured by computerized tomography and reconstructed with a Synapse Vincent volumetric analyzer. Using this system, we predicted the renal vascular territory and other trauma areas involved in renorrhaphy. All measurements were taken within 3 and 6 months pre- and postoperatively, respectively.

The actual postoperative renal parenchymal volume was significantly correlated with the virtual predicted residual renal volume excluding the tumor and resected margin (r = 0.435, p <0.05). The ratio of split estimated glomerular filtration rate (eGFR) postoperative/preoperative) was significantly correlated with the virtual predicted residual renal volume excluding the resected margin and the traumatic area by renorrhaphy (r = 0.401, p <0.05).

When predicting the reduction of renal function of the diseased side following partial nephrectomy, adding the extent of the area traumatized by renorrhaphy might be useful for predicting the postoperative split renal function of the affected kidney.