文献类型：会议论文

英文题名：DESIGN OF A NOVEL ELECTRODE OF RADIOFREQUENCY ABLATION FOR LARGE TUMORS: A FINITE ELEMENT STUDY

作者：Fang, Zheng[1];Zhang, Bing[2,6];Moser, Michael[3];Zhang, Edwin[4];Zhang, Wenjun[5]

机构：[1]East China Univ Sci & Technol, CISR Lab, Tumor Ablat Grp, Shanghai, Peoples R China;[2]Univ Saskatchewan, Div Biomed Engn, Saskatoon, SK, Canada;[3]Univ Saskatchewan, Dept Surg, Saskatoon, SK, Canada;[4]Univ Toronto, Div Vasc & Intervent Radiol, Dept Med Imaging, Toronto, ON, Canada;[5]Univ Saskatchewan, Dept Mech Engn, Saskatoon, SK, Canada;[6]East China Univ Sci & Technol, Shanghai, Peoples R China

会议论文集：ASME International Mechanical Engineering Congress and Exposition

会议日期：NOV 03-09, 2017

会议地点：Tampa, FL

语种：英文

外文关键词：expandable electrode; finite element method model; large ablation volume; radiofrequency ablation; sphericity index

摘要：Objective: The aim of this study was to design a novel radiofrequency (RF) electrode for larger and more round ablation volumes and its ability to achieve the complete ablation of liver tumors (> 3 cm in diameter) using finite element method. Methods: A new RF expandable electrode comprising three parts (i.e., insulated shaft, changing shaft, and hooks) was designed. Two modes of this new electrode (i.e., monopolar expandable electrode (MEE) and hybrid expandable electrode (HEE)) and a commercial expandable electrode (CEE) were investigated using liver tissue with and without liver tumor. A temperature controlled radiofrequency ablation (RFA) protocol with a target temperature of 95 degrees C and an ablation time of 15 minutes was used in this study. Both the volume and shape of the ablation zone were studied for all RF electrodes. A large liver tumor with the diameter of 3.5 cm was used to evaluate the effectiveness on the complete ablation of the new designed electrode. Results: In the first scenario (without liver tumor), the ablation volumes of CEE, HEE, and MEE were 9.96 cm(3), 41.0 cm(3), and 46.14 cm(3), respectively. The values of sphericity index (Si) of CEE, HEE, and MEE were 0.36, 0.94, and 0.98, respectively. The best performance was achieved by the MEE electrode. In the second scenario (with liver tumor), the ablation volumes of MEE and CEE were 67.56 cm(3) and 20.62 cm(3), respectively. Also, a rounder ablation volume was generated by MEE compared to CEE (SI: 0.98 vs 0.55). Conclusion: This study concludes that compared with CEE, both MEE and HEE are able to get larger and more round ablation volumes due to the larger electrode tissue interface and more round shape of hooks; compared with HEE, MEE is better to get a larger and rounder ablation volume; MEE is able to ablate a large liver tumor (i.e., 3.5 cm in diameter) completely.