Endoloop-assisted laparoscopic partial nephrectomy

Purpose: To determine the safety and feasibility of Endoloop-assisted laparoscopic partial nephrectomy in a large-animal model. Materials and Methods: Twelve female Yucatan mini-pigs underwent either left (N = 6) or right (N = 6) transperitoneal laparoscopic lower-pole nephrectomy following cinching of a 1-0 Vicryl suture loop (Endoloop) proximal to the resected lower pole until ischemic discoloration was achieved. The ischemic lower pole was excised with Endo-scissors and the lower pole removed using a laparoscopic bag. Follow-up involved evaluation under anesthesia with retrograde pyelography and intravenous urography and subsequent sacrifice for pathologic evaluation at 3 (N = 4), 14 (N = 4), or 60 (N = 4) days. Results: All procedures were completed successfully. In two cases, the Endoloop slipped off the retained parenchyma. Both problems were corrected immediately with no sequelae. At sacrifice, all upper-pole renal segments functioned, as shown by urography, and no urinomas or abscesses were found. In one animal, there was moderate hydronephrosis presumably secondary to ureteral scarring, and in another, mild extravasation was demonstrated on the retrograde pyelogram. Conclusion: We were able to perform laparoscopic partial nephrectomy with the Endoloop safely and effectively in the current model. Modification of the Endoloop to allow more controlled pressure application may allow clinical application of this method for polar laparoscopic partial nephrectomy.