ABSTRACT
Objective To explore the technique and feasibility of using 1.5 T MR guided radiofrequency ablation (RFA) of hepatic malignant tumor. Methods Twenty three patients with 44 malignant lesions in liver confirmed by pathology were treated with 1.5 T MR guided RFA using MR compatible multipolar RF electrode. Only patients refusing open surgery or suffering from unresectable lesions were included. Of these, 11 patients had primary hepatic carcinoma and 12 patients had hepatic metastases. The mean maximal diameter of lesions was (3.3 ± 1.8)cm. Postoperative MR was performed; the ablation zone covered and exceeded 0.5 to 1.0 cm to the margin of initial tumor was considered successful. Results All ablations were successful and lesions created by radio frequency were large enough to cover the initial tumor volume in all cases. No severe complications such as biliary fistula, perforation of diaphragmatic muscle,postoperative jaundice and pneumothorax were encountered. The mean operative time was (93 ± 33 ) min.The RF electrodes appeared in MRI as low signal structure. The ablation lesions were well-defined hyperintensity in T1 WI and hypo-intensity with a thin rim of high signal intensity on T2WI and DWI. Conclusion 1.5 T MR guided RFA of hepatic malignant tumor is an effective and safe technique.