Novel balloon catheter‐based endobiliary radiofrequency ablation system: Ex‐vivo experimental study

Background Endobiliary radiofrequency ablation (RFA) is a promising treatment option for malignant biliary obstruction, but conventional catheter RFA (Conventional‐RFA) has several limitations. We examined the feasibility of a novel approach to balloon‐based RFA (Balloon‐RFA) with an automatic temperature control system in freshly resected pig livers. Methods Balloon‐RFA application was performed in a step‐by‐step manner at target temperatures of 50°C, 60°C, and 70°C. The temperatures were maintained for 60 s. As a control, Conventional‐RFA was performed at 7 W of power for 90 s, 7 W 120 s, 10 W 90 s, and 10 W 120 s. The ablation areas were measured and compared between Balloon‐RFA and Conventional‐RFA. Results The maximum ablation depths in Balloon‐RFA were 1.86 ± 0.53, 2.29 ± 0.31, and 3.19 ± 0.47 mm at target temperatures of 50, 60, and 70°C, respectively. The maximum ablation depths in Conventional‐RFA were 2.81 ± 0.46, 4.09 ± 0.45, 3.41 ± 0.58, and 4.27 ± 0.29 mm at 7 W 90 s, 7 W 120 s, 10 W 90 s, and 10 W 120 s, respectively. Differences between the minimum and maximum depths were significantly smaller in Balloon‐RFA (0.73 ± 0.31 mm) than in Conventional‐RFA (2.00 ± 0.62 mm; P