MRI-Guided Radiofrequency Thermal Ablation of Normal Lung Tissue: In Vivo Study in a Rabbit Model

Abstract

OBJECTIVE. The purpose of this study was to assess the feasibility of MRI to guide and monitor radiofrequency ablation of normal pulmonary tissue in a rabbit model. MATERIALS AND METHODS. Percutaneous puncture and lung radiofrequency ablation were performed in six New Zealand white rabbits under MRI control using a 0.2-T open MRI scanner. Technical feasibility and complication detection were evaluated. The ablation zone appearance and size were assessed using MRI, CT, and gross pathology. Interclass correlation coefficients (ICCs) of the maximum short-axis diameters of the lesions on gross pathology and the corresponding diameters as measured on each MRI pulse sequence and on CT scans were calculated. RESULTS. MRI guidance of percutaneous puncture and radiofrequency ablation of pulmonary tissue is feasible. A pneumothorax was detected and treated using MRI. In the specimen, the mean coagulation necrosis diameter was 9.8 mm. The T1-weighted spoiled gradient-echo fast low-angle shot images showed the highest ICC (0.81) for the thermal lesion diameter. CONCLUSION. Our results indicate that MRI guidance is feasible and useful for radiofrequency ablation of normal pulmonary tissue.