Department of Diagnostic Radiology, College of Medicine, Hanyang University
Published online: September 1, 2001.
ABSTRACT
PURPOSE: To assess the effect of ethanol infusion on the size of ablated lesion during radiofrequency (RF) thermal ablation. MATERIALS AND METHODS: We performed an ex vivo experimental study using a total of 15 pig livers. Three groups were designed; 1) normal control (n=10), 2) saline infusion (n=10), 3) ethanol infusion (n=10). Two radiofrequency ablations were done using a 50 watt RF generator and a 15 guage expandable electrodes with four prongs in each liver. During ablation for 8 minutes, continuous infusion of fluid at a rate of 0.5 ml/min through the side arm of electrode was performed. We checked the frequency of the "impeded-out" phenomenon due to abrupt increase of impedance during ablation. Size of ablated lesion was measured according to length, width, height, and subsequently volume after the ablations. The sizes of the ablated lesions were compared between the three groups. RESULTS: "Impeded-out" phenomenon during ablation was noted 4 times in control group, although that has never happened in saline or ethanol infusion groups. There were significant ifferences in the volumes of ablated lesions between control group (10.62 +/-1.45 cm3) and saline infusion group (15.33 +/-2.47 cm3), and saline infusion group and ethanol infusion group 18.78 +/-3.58 cm3) (p<.05). CONCLUSION: Fluid infusion during radiofrequency thermal blation decreases a chance of charring and increase the volume of the ablated lesion. Ethanol infusion during ablation may induce larger volume of ablated lesion than saline infusion.