Laparoscopic partial nephrectomy using the potassium titanyl phosphate laser in a porcine model

To evaluate the potential and feasibility of the potassium titanyl phosphate (KTP) Greenlight laser to perform partial nephrectomy in a porcine model.

A total of 15 laparoscopic partial nephrectomies were performed in 4 Danish land-raised pigs under anesthesia. Transperitoneal access was obtained, and using a total of four ports, the 80-W KTP laser was used to perform bilateral upper and lower pole partial nephrectomy. The procedures were done successfully without renal cooling or clamping of the vessels. The estimated blood loss for each procedure was less than 30 mL. Only in one operation, in which a secondary renal vein was transected, was any additional hemostasis required (a single Endoclip). The mean operating time was 42 minutes (range 31 to 59) for each partial nephrectomy. As demonstrated on video, smoke formation was, at times, a problem during the procedure, because it reduced visibility, making only intermittent application of laser energy possible. Histopathologic analysis of the specimens showed a zone of loss of substance (less than 1 mm) at the resection line and narrow adjacent zones on both sides of the resection line with minimal changes.

We have shown for the first time that normally perfused laparoscopic partial nephrectomy using the KTP laser is feasible and efficacious in the porcine model. This represents a novel application for the KTP laser, which produced excellent renal parenchymal hemostatic ablation. We are currently working on ways to improve the visibility by reducing smoke formation before undertaking a clinical trial in humans.