www.kjurology.org DOI:10.4111/kju.2011.52.1.44 Endourology/Urolithiasis Feasibility of Laparoendoscopic Single-Site Partial Nephrectomy in a Porcine Model Dong-Hun Koo, Yong Hyun Park, Chang Wook Jeong1, Hyeon Jeong2, Hyeon Hoe Kim, Seung Bae Lee2 Department of Urology, Seoul National University College of Medicine, Seoul, 1Seoul National University Bundang Hospital, Seongnam, 2Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea Purpose: We performed laparoendoscopic single-site (LESS) partial nephrectomy in a porcine model with the objectives of overcoming the technical challenges of this sur- gery and exploring its feasibility. Materials and Methods: Six partial nephrectomies were performed on a pig aged 5 months, three cases on each kidney, by four surgeons: two urologists with much experi- ence in laparoscopic surgery (E1, E2) and two less-experienced urologists (B1, B2). While under general anesthesia, the swine was placed in a lateral flank position. Umbilical placement of an Octoport was done with a 2.5 cm incision. After dissection of the renal hilum and Gerota's fascia, a bulldog clamp was applied on the renal artery and parenchymal resection was done. Renorrhaphy was then performed with inter- rupted sutures with the use of a sliding knot technique. Results: All six partial nephrectomies were performed successfully after repair of the vascular and collecting system at the resection margin and renorrhaphy without the need to introduce any additional ports. There were no noticeable intra- or postoperative complications. The mean warm ischemic time was 42 minutes (range, 30-60 minutes). The shortest warm ischemic time, 30 minutes, was achieved by using the early unclamp- ing technique during renorrhaphy. The longest warm ischemic time was 60 minutes. The average number of renorrhaphy stitches was 3.2 (range, 2-5). Conclusions: LESS partial nephrectomy was successfully performed in a porcine model but resulted in a longer ischemic time than that of conventional laparoscopic surgeries. Therefore, further laboratory disciplinary efforts are needed to decrease the warm is- chemic time and to improve this surgical technique. Key Words: Kidney neoplasms; Laparoscopy; Nephrectomy This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Article History: received 24 November, 2010 accepted 18 December, 2010 Corresponding Author: Seung Bae Lee Department of Urology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, 39, Boramae-gil, Dongjak-gu, Seoul 156-707, Korea TEL: +82-2-870-2393 FAX: +82-2-831-2826 E-mail: sblee@brm.co.kr This research was supported by the Research Foundation Grant funded by the Seoul National University Hospital (0420090340) INTRODUCTION Since its introduction by Clayman et al, laparoscopic sur- gery has enabled great progress in the area of urology, and less invasive techniques such as laparoendoscopic single- site surgery (LESS) and natural orifice transluminal endo- scopic surgery (NOTES) have recently been introduced to clinical practice [1]. Minimally invasive procedures such as LESS and NOTES have an aesthetic advantage over con- ventional laparoscopic surgeries because they require few- er portals of entry, which leaves minimal to almost no evi- dent surgical scars. 　Laparoscopic partial nephrectomy is performed as the surgery of choice for small renal tumors with established evidence [2], and the surgical effectiveness and overall on- cological outcomes of this procedure have been proved to be equal to those of conventional open surgeries for selected patients, even in the case of locally advanced renal tumors [3]. For radical nephrectomy, the LESS technique is cur- rently being practiced in many institutions, and its effec- tiveness has already been established. However, in the case of partial nephrectomy, the LESS technique is not yet Korean Journal of Urology Ⓒ The Korean Urological Association, 2011 44 Korean J Urol 2011;52:44-48