Safety and effect on ablation size of hydrochloric acid-perfused radiofrequency ablation in animal livers

Purpose: Our objective was to determine the safety and ablation size of hydrochloric acid-perfused radiofrequency ablation (HCl-RFA) in liver tissues, prospectively using in vivo rabbit and ex vivo porcine liver models.

Materials and methods: The livers in 30 rabbits were treated in vivo with perfusions of normal saline (controls) and HCl concentrations of 5%, 10%, 15%, and 20%, during RFA at 103?°C and 30?W for 3?min. For each experimental setting, six ablations were created. Safety was assessed by comparing baseline weight and selected laboratory values with those at 2, 7, and 14 days’ post-ablation, and by histopathological analysis. The livers in 25 pigs were treated ex vivo with the same five perfusions during RFA at 103?°C, at both 30?W and 60?W, for 30?min. Ablation diameters and volumes were measured by two examiners.

Results: Rabbit weights and selected laboratory values did not differ significantly from baseline to 7 and 14 days’ post-ablation, liver tissues outside the ablation zones were normal histologically, and adjacent organs showed no macroscopic damage. The mean ablation volumes in the porcine livers treated with HCl-RFA were all larger than those treated with normal saline perfusion during RFA (NS-RFA), at both 30?W and 60?W (p?3 and 6.84 (SD?=?0.36) cm, respectively.

Conclusions: Based on our experiments, HCl-RFA in the liver appears to be as safe as NS-RFA while also resulting in larger ablation zones.