2024 Volume 37 Issue 1 Pages 165-172
The aim of this study was to investigate changes in split renal function after minimally invasive surgery in patients with small renal masses. One hundred and thirty-one patients who underwent laparoscopic or robot-assisted laparoscopic partial nephrectomy and had a functioning contralateral kidney and whose split renal function was assessed preoperatively and postoperatively were enrolled in this study. Split renal function was assessed using mercaptoacetyltriglycine technetium (99mTc-MAG3) scintigraphy. The median age was 66 years, and the median mass diameter was 2.7 cm. Of those patients, 66 underwent robot-assisted partial nephrectomy. The number of patients with tumors classified as having low, intermediate, and high complexity according to R.E.N.A.L nephrometry scores were 72, 52, and 7, respectively. The median surgical time and warm ischemic time were 223 and 22 minutes, respectively. Pathological examination revealed renal cell carcinoma in 121 (92.4％) patients. With 99mTc-MAG3 renal scintigraphy, corrected effective renal plasma flow (cERPF) in the unaffected kidney increased by 5.4％ postoperatively, while cERPF in the affected kidney decreased by 21.6％ postoperatively. Multiple linear regression analyses revealed that factors predicting a greater reduction in cERPF in the affected kidney included a high complexity R.E.N.A.L nephrometry score, longer operative time, performance of renal calyceal repair, and higher preoperative cERPF in the affected and total kidneys. Both the amount and rate of reduction in cERPF in the affected and total kidneys were smaller when the total cERPF was ≦203 mL/min/1.73 m2 than when the total cERPF was ≧204 mL/min/1.73 m2.
