Adjuvant Thermal Accelerant Gel Use Increases Microwave Ablation Zone Temperature in Porcine Liver as Measured by MR Thermometry.

Abstract Purpose To determine the effects of a thermal accelerant gel on temperature parameters during microwave liver ablation. Materials and Methods Sixteen consecutive liver ablations were performed in 5 domestic swine under general anesthesia with (n = 8) and without (n = 8) administration of thermal accelerant gel. Ablation zone temperature was assessed by real-time MR thermometry, measured as maximum temperature (Tmax) and the volume of tissue ≥ 60°C (V60). Tissue heating rate, ablation zone shape, and thermal energy deposition using the temperature degree-minutes at 43°C (TDM43) index were also measured. Differences between groups were analyzed using generalized mixed modeling with significance set at P = .05. Results Mean peak ablation zone temperature was significantly greater with thermal accelerant use (mean Tmax, thermal accelerant: 120.0°C, 95% confidence interval [CI] 113.0°C–126.9°C; mean Tmax, control: 80.3°C, 95% CI 72.7°C–88.0°C; P Conclusions Thermal accelerant use is associated with higher microwave ablation zone temperatures, greater thermal energy deposition, and faster and more spherical tissue heating compared with control ablations.