RESUMO
Objective To evaluate the validity of percutaneous radiofrequency ablation(RFA)combined with percutaneous ethanol injection(PEI) with different style in rabbit liver in vivo.Methods Twenty-four New Zealand white rabbits were included in this study and divided into four groups.Group A:RFA before PEI(n=6),RFA (1 cm mono-electrode,maintain 3 minutes RFA) before PEI 1.5 ml; Group B:PEI before RFA (n=6),PEI 1.5 ml before RFA (1 cm mono-electrode,maintain 3 minutes RFA); Group C:RFA (1 cm mono-electrode,maintain 3 minutes RFA) only (n =6);Group D:PEI (1.5 ml) only(n=6).To analyze the resistance,current and energy requirement per unit of each group including RFA.To observe the size,shape,isoperimetric ratio and volume of coagulated necrosis of each group by enhanced CT.Results The longest diameter and the shortest diameter of group B[respectirely,(24.1±4.4) mmand (21.45±4.0) mm] were significantly larger than group C [respectirely,(12.4 ± 1.6) mm and (11.1 ± 1.4) mm] and group D[respectirely,(7.7 ± 2.3) mm and (5.1 ± 1.5) mm] (P＜0.01).The height diameter and volume of coagulated necrosis of group B [respectirely,(20.3± 4.9) mm3 and (5879 ± 2607) mm3] were significantly larger than the other 3 groups [(14.8± 2.7) mm3 and (3130±1250) mm3,(10.7±1.6) mm3 and (767±173) mm3,(6.7± 1.0) mm3 and (146±83) mm3] in A,C,and a group (P＜0.01).Isoperimetric ratios of ablation zone in group B was the most highest.There were no statistically significant between each group (P＞0.05).The resistance of group B were significantly larger than group A and group C (P＜0.01).The current of group B were significantly lower than group A and group C (P＜0.05).The energy requirement per unit of group A and group B were significantly lower than group C (P＜0.01).Conclusion The volume of coagulated necrosis of group PEI-RFA was significantly larger than the other 3 groups.The energy requirement per unit of group PEI-RFA were the lowest in each group.The isoperimetric ratio of group PEI-RFA was the most highest.