Rustagi Tarun, Gleeson Ferga C, Abu Dayyeh Barham K, Topazian Mark D, Levy Michael J
Division of Gastroenterology, Mayo Clinic, Rochester, MN.
J Clin Gastroenterol. 2018 Feb;52(2):168-171. doi: 10.1097/MCG.0000000000000808.
Percutaneous and intraoperative radiofrequency ablation (RFA) has become a valued tool in the management of primary and secondary hepatic lesions. A recent FDA-approved endoscopic ultrasound (EUS)-guided RFA probe now offers promise to help manage such lesions. However, there are no data to determine the ideal power setting and duration of ablation needed to effectively treat hepatic masses. The aim of the study was to evaluate the macroscopic zone of hepatic injury for EUS-RFA using a variety of settings within a fresh porcine hepatic specimen.
RFA was performed using the Habib EUS-RFA needle (EMcision Ltd, London, UK) which is a 1-Fr wire (0.33 mm, 0.013 inch) with a working length of 190 cm. A step by step approach to deliver radiofrequency energy at 5, 10, 15, 20, and 50 W of power and 10, 30, 60, 90, 120, and 300 seconds, respectively, was followed. Macroscopic and microscopic findings of the ablation zone were evaluated at each setting.
The maximal zone (diameter, 8.2±0.14 mm; length, 20.85±0.21 mm) of coagulative necrosis was achieved using an ablation power of 10 W for duration of 90 seconds. Notably, increased power settings resulted in an unexpected and diminished effect on tissue destruction.
Our findings support the use of 10 W power for 90 seconds for maximum ablation in the liver. Our data also provide initial guidance and alternate settings to be considered when performing EUS-RFA to adjust the ablation power and duration to match the lesion size, shape, and risk of injury to adjacent structures.
经皮和术中射频消融（RFA）已成为原发性和继发性肝脏病变治疗中的一项重要工具。最近，美国食品药品监督管理局（FDA）批准的内镜超声（EUS）引导下的RFA探头有望用于此类病变的治疗。然而，目前尚无数据确定有效治疗肝脏肿块所需的理想功率设置和消融持续时间。本研究的目的是在新鲜猪肝脏标本中，使用多种设置评估EUS-RFA造成的肝脏损伤宏观区域。
使用Habib EUS-RFA针（英国伦敦EMcision有限公司）进行RFA，该针为1-Fr导线（0.33 mm，0.013英寸），工作长度为190 cm。采用逐步方法，分别以5、10、15、20和50 W的功率以及10、30、60、90、120和300秒的时间传递射频能量。在每个设置下评估消融区的宏观和微观表现。
使用10 W的消融功率持续90秒可实现最大凝固性坏死区域（直径8.2±0.14 mm；长度20.85±0.21 mm）。值得注意的是，功率设置增加导致对组织破坏的效果意外降低。
我们的研究结果支持在肝脏中使用10 W功率持续90秒进行最大程度的消融。我们的数据还提供了初步指导和其他设置，在进行EUS-RFA时可考虑这些设置，以调整消融功率和持续时间，使其与病变大小、形状以及对相邻结构的损伤风险相匹配。
