GreenLight (532 nm) Laser Partial Nephrectomy Followed by Suturing of Collecting System Without Renal Hilar Clamping in Porcine Model

Abstract

To assess the feasibility of partial nephrectomy (PN) without renal hilar clamping using the 80-W GreenLight (532 nm) laser with opening of the collecting system followed by its suture in a porcine model. We performed 12 open laser PNs in 6 farm pigs. We used the technique of incisional laser ablation of the lower pole of the right kidney. The pigs were kept alive, and 2 weeks later, underwent the same technique on the left kidney, followed by immediate killing. We recorded the acute and chronic outcomes. Renal parenchyma resection was achieved solely with the laser. The collecting system was opened with the laser in each procedure. All renal specimens underwent retrograde pyelography and histologic examination. All procedures were completed without renal hilar clamping. The mean operative and laser time was 67.1 +/- 20.6 minutes (range 35-95) and 17.8 +/- 6.4 minutes (range 10-30), respectively. The mean resected kidney mass was 17% +/- 0.5% (range 10%-27%) of the total kidney mass. The mean blood loss was 142.5 +/- 88.9 mL (range 50-350). No evidence of urinary extravasation was seen after the acute procedures, but proven urinomas with decayed suture were found after all chronic procedures. PN using the GreenLight laser is a feasible method for renal parenchyma incisional ablation. The laser hemostatic effect of interlobar vessel bleeding is safe and sufficient. The sutured collecting system after laser PN cannot heal in the thermically damaged tissue. The method is applicable to peripherally located lesions, without entering the collecting system. More prospective animal studies are necessary before application in humans.