MR-guided microwave thermocoagulation therapy of liver tumors: Initial clinical experiences using a 0.5 T open MR system

Purpose: To utilize a microwave coagulator for MR-guided interstitial thermal therapy of liver tumors as a clinically feasible heating device. Materials and Methods: MR-guided microwave thermocoagulation therapy was carried out 34 times in 30 patients with liver tumors (eight hepatocellular carcinoma, 22 metastatic tumors) using a 0.5 T open configuration MR system. Results: Percutaneous puncture could be accomplished both accurately and safely while monitoring real-time magnetic resonance imaging (MRI). Using a notch filter, MR images could be observed without electromagnetic interference even during microwave ablation. Temperature monitoring during ablation was possible using the proton resonance frequency method. All procedures could be successfully carried out without any complications, and the therapeutic effects were deemed satisfactory. Conclusion: MR-guided microwave thermocoagulation therapy could be one promising procedure of minimally invasive treatment for liver tumors.