MR-guided radiofrequency ablation of hepatic malignancies at 1.5 T: Initial results

Abstract

Purpose To assess the feasibility of magnetic resonance (MR)‐guided radiofrequency ablation (RFA) of hepatic malignancies using a high‐field MR scanner. Materials and Methods A total of 10 patients with 14 primary (N = 1) or secondary (N = 13) hepatic malignancies underwent MR‐guided RFA using a closed‐bore 1.5 T MR scanner. Lesion diameters ranged from 2.0 cm to 4.7 cm. RFA was performed using a 200‐W generator in combination with a 3.5‐cm LeVeen electrode applying a standardized energy protocol. Results RFA was technically feasible in all patients. Necrosis diameter ranged from 2.5 cm to 6.8 cm. The mean follow‐up period is 12.2 (1–18) months. In nine out of 10 patients, local tumor control was achieved. For this purpose, a second CT‐guided RFA was required in two patients. In four patients, multifocal hepatic tumor progression occurred, with the treated lesion remaining tumor‐free in three of these patients. Two patients showed extrahepatic tumor progression. Four patients remained tumor‐free. No major complications occurred. Conclusion MR‐guided RFA of hepatic malignancies in a closed‐bore high‐field MR scanner is technically feasible and safe. It can be advantageous in locations considered unfavorable for CT‐guided puncture or in patients in which iodinated contrast material is contraindicated. J. Magn. Reson. Imaging 2004;19:342–348.