In Vivo Experimental Study on the Effects of Fluid in Increasing the Efficiency of Radiofrequency Ablation

Background: Radiofrequency ablation (RFA) is the most widely used and studied method internationallyfor the local treatment of liver tumors. However, the extension of coagulation necrosis in one RFA procedureis limited and incomplete coverage of the damaged area can lead to a high local recurrence rate.
Objective: Inthis study, we compared the effects of different solutions in enhancing hepatic radiofrequency by establishinga rabbit VX2 liver cancer model. We also determined the optimal solution to maximise effects on the extent ofRFA-induced coagulation necrosis.
Methods: Thirty VX2 tumor rabbits were randomly assigned to five groups:group A, RFA alone; group B, RFA with anhydrous ethanol injection; group C, RFA with 5% hypertonic salineinjection; group D, RFA with lidocaine injection; and group E, RFA with a mixed solution. Routine ultrasoundexaminations and contrast-enhanced ultrasound (CEUS) of the ablation areas were performed after RFA. Then,we measured the major axis and transverse diameter and compared the areas of coagulation necrosis inducedby RFA.
Results: The mean ablation area range increased in groups B, C and especially E, and the scopes weregreater compared with group A. Preoperative application of anhydrous ethanol, hypertonic saline, lidocaineand the mixed solution (groups B, C, D and E, respectively) resulted in larger coagulation necrosis areas than ingroup A (p<0.05). Among the groups, the coagulation necrosis areas in group E was largest, and the differencewas statistically significant compared with other groups (p<0.05). Pathological findings were consistent withimaging results.
Conclusions: A mixture of dehydrated alcohol, hypertonic saline and lidocaine injected withRFA increases the extent of coagulation necrosis in the liver with a single application, and the mixed solution ismore effective than any other injection alone.