Evaluation of radiofrequency ablation using a 1-Fr wire electrode in porcine pancreas, liver, gallbladder, spleen, kidney, stomach, and lymph nodes: A pilot study

Background and Aim: The frequency of detecting asymptomatic incidental lesions of the pancreas is increasing. A substantial number of these lesions are either malignant or premalignant, thus mandating pancreatic resection. A less invasive treatment option may be feasible for selected patients. Endoscopic ultrasound-guided radiofrequency ablation (RFA) may be offered as a treatment option for these patients. The objective of the present study was to evaluate the performance characteristics of monopolar RFA using a 1-Fr wire electrode in porcine pancreas, liver, gallbladder, spleen, kidney, stomach, and lymph nodes. Methods: Six Yorkshire pigs were used for this study. The internal organs were accessed after a midline laparotomy. Manual monopolar RFAs were carried out over a 90-s period using a wide range of power settings (3, 4, 5, 10, 15, and 25 W). The pancreas was exposed at all power settings; the other organs were exposed at power settings of 3, 4, 5, and 10 W. Maximum diameter of coagulative necrosis was measured. Results: In all study animals, RFA was carried out in the target organs without difficulty. Only the pancreas showed definite coagulative necrosis. Maximum diameter of coagulative necrosis (8.0 +/- 1.7 mm) was achieved at 5W. No definite coagulative necrosis was noted in the other organs. Conclusions: Monopolar RFA using a 1-Fr wire electrode resulted in coagulative necrosis in porcine pancreas. RFA at higher power settings resulted in relatively homogeneous necrosis. At a given power setting, the RFA effect is likely to differ according to electrical properties of the target tissue.