Abstract:Objective:To compare radiofrequency ablation(RFA) alone and RFA combined with ethanol injection(EI) by multi-pronged injection needle(Quadra-Fuse) in ablating the pig liver. Methods:Twelve pigs were divided into two groups. Groups A underwent a combination of RFA and EI ablation of the liver, group B underwent RFA alone as control. All pigs were sacrificed immediately after treatment. Ablated area with surrounding liver parenchyma was excised for gross and histological examination. Results:The longest diameter of ablation area of the liver was 4.7±0.4cm and 4.1±0.2cm in group A and group B, respectively (P<0.05). The durations of ablation in group A and group B were 9.8±0.9 and 14.7±1.3min, respectively (P<0.05). Histological staining revealed no viable hepatocytes from the center to margins of the ablated area in two groups. There was a zone of transition surrounding the ablated necrotic area that showed hepatocytes degeneration, necrosis, hyperemia and hemorrhage, etc; infiltration of leucocytes and lymphocytes could be seen in tissues 1cm distal to the margin of necrotic area. Conclusions:RFA combined with ethanol injection can induce more great necrotic area and short ablating time than that of RFA alone did in normal pig liver tissue.