Yoon S, Ji WB, Um JW, Hong KD. Optimizing radiofrequency ablation parameters for perianal fistula treatment: A porcine model study. World J Gastrointest Surg 2026; 18(5): 119504 [DOI: 10.4240/wjgs.v18.i5.119504]
Corresponding Author of This Article
Kwang Dae Hong, MD, PhD, Professor, Colorectal Surgery, Korea University Ansan Hospital, 123 Joekgum-ro, Danwon-gu, Ansan 15355, South Korea. drhkd@korea.ac.kr
Research Domain of This Article
Gastroenterology & Hepatology
Article-Type of This Article
research-article
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Baishideng Publishing Group Inc, 7041 Koll Center Parkway, Suite 160, Pleasanton, CA 94566, USA
Share the Article
Yoon S, Ji WB, Um JW, Hong KD. Optimizing radiofrequency ablation parameters for perianal fistula treatment: A porcine model study. World J Gastrointest Surg 2026; 18(5): 119504 [DOI: 10.4240/wjgs.v18.i5.119504]
World J Gastrointest Surg. May 27, 2026; 18(5): 119504 Published online May 27, 2026. doi: 10.4240/wjgs.v18.i5.119504
Optimizing radiofrequency ablation parameters for perianal fistula treatment: A porcine model study
Sunseok Yoon, Woong Bae Ji, Jun Won Um, Kwang Dae Hong
Sunseok Yoon, Woong Bae Ji, Jun Won Um, Kwang Dae Hong, Colorectal Surgery, Korea University Ansan Hospital, Ansan 15355, South Korea
Author contributions: Yoon S and Hong KD designed and coordinated the study; Yoon S and Hong KD performed the experiments and acquired and analyzed the data; Ji WB and Um JW interpreted the data; Yoon S wrote the manuscript. All authors approved the final version of the article.
AI contribution statement: we used ChatGPT-4o primarily for English translation, language polishing, and sentence-level refinement of author-prepared content.
Supported by Korea University Ansan Hospital, No. O2310671; Seoul R&BD Program, No. BT250226; and RF Medical Co., Ltd., Seoul, Republic of Korea.
Institutional animal care and use committee statement: The study was conducted in accordance with the guidelines of the American Veterinary Medical Association (AVMA) for the euthanasia of animals and was approved by the Institutional Animal Care and Use Committee (IACUC) of Cronex Inc., Seoul, Republic of Korea (Protocol Code: CRONEX-IACUC: 202302002).
Conflict-of-interest statement: The authors declare no conflict of interest.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Data sharing statement: The raw data supporting the conclusions of this article will be made available by the authors on request.
Corresponding author: Kwang Dae Hong, MD, PhD, Professor, Colorectal Surgery, Korea University Ansan Hospital, 123 Joekgum-ro, Danwon-gu, Ansan 15355, South Korea. drhkd@korea.ac.kr
Received: January 30, 2026 Revised: February 13, 2026 Accepted: March 13, 2026 Published online: May 27, 2026 Processing time: 118 Days and 1.3 Hours
Abstract
BACKGROUND
The effective treatment of perianal fistulas while ensuring sphincter preservation remains challenging. Radiofrequency ablation (RFA) is a promising approach; however, its clinical translation is limited because energy settings have been extrapolated from non-fistulous tissues, and most probes deliver only focal heating. We designed a 50-mm segmental RFA catheter to achieve maximal granulation tissue ablation while maintaining uniformity along the tract.
AIM
To identify the optimal temperature-time parameters for uniform, effective endoluminal RFA of perianal fistulas.
METHODS
Ex vivo screening in fresh pork loin selected four candidate energy settings defined by temperature and duration: 120 °C/20 seconds, 120 °C/24 seconds, 100 °C/20 seconds, 100 °C/24 seconds. These were applied endoluminally to the perianal fistula tracts created in four pigs. After RFA, each tract was divided into the inner, middle, and outer thirds for histological analysis. The primary endpoint was the ablation-to-granulation tissue area ratio, and burn depth was summarized as the equivalent radius (re).
RESULTS
The 120 °C/24 seconds setting achieved the highest ablation-to-granulation ratio (70.9 ± 7.5%), exceeding 120 °C/20 seconds (51.9 ± 8.3%), 100 °C/20 seconds (46.9 ± 4.0%), 100 °C/24 seconds (43.7 ± 6.1%). It also produced the greatest burn depth (re 0.46 ± 0.05 mm vs 0.30 ± 0.04 mm, 0.24 ± 0.03 mm, and 0.19 ± 0.03 mm; all pairwise P < 0.001). The depth was consistent across segments.
CONCLUSION
In a porcine fistula model, segmental RFA at 120 °C for 24 seconds produced the deepest, most homogeneous ablation, supporting its use as a reference setting for further studies.
Core Tip: Endoluminal radiofrequency ablation (RFA) is a sphincter-preserving option for perianal fistulas. However, standardized energy settings validated in true fistula tissue are lacking. Using a porcine model of perianal fistula, we performed ex vivo prescreening and in vivo histological validation of four candidate settings with a 50-mm segmental RFA catheter. The 120 °C/24 seconds setting produced the most effective ablation (highest ablation/granulation ratio) with the deepest and most consistent burn depth along the tract, providing a practical reference parameter for further translational studies.
