Interactive MRI-guided radiofrequency interstitial thermal ablation of abdominal tumors: Clinical trial for evaluation of safety and feasibility

This clinical trial was performed to evaluate the safety and feasibility of interactive MR-guided radiofrequency (RF) interstitial thermal ablation (I TA) performed entirely within the MR imager. RF-ITA was performed on 11 int ra-abdominal metastatic tumors during 13 sessions. The RF electrode was pla ced under MR guidance on a .2-T system using rapid fast imaging with steady state precession (FISP) and true FISP images. A custom 17-gauge electrode was used and was modified in four sessions to allow circulation of iced sal ine for cooling during ablation. Tissue necrosis monitoring and electrode r epositioning were based on rapid TP-weighted and short-inversion-time inver sion recovery (STIR) sequences. Morbidity and toxicity were assessed by cli nical and imaging criteria. The region of tissue destruction was visible in all 11 tumors treated, as confirmed on subsequent contrast-enhanced images . Mo significant morbidity was noted, and patient discomfort was minimal. I n conclusion, interactive MR-guided RF-ITA is feasible on a clinical .2-T C -arm system with supplemental interventional accessories with only minor pa tient morbidity. The ability to completely ablate tumors with RF-ITA depend s on tumor size and vascularity.