Design of a System for Magnetic-Resonance-Guided Irreversible Electroporation

Irreversible electroporation (IRE) is a non-thermal tumor ablation method where strong electrical fields between at least two electrodes are used and can be seen as an alternative to thermal ablation techniques. The therapy outcome directly dependents on the position of the electrodes. Real-time monitoring of the IRE by magnetic resonance imaging (MRI) would allow to detect unwanted electrode displacement and to apply visualization methods for the ablation area. This requires that the IRE generator does not significantly interfere with the MRI. Currently, there is no IRE generator available designed for MRI-guided IRE.This paper presents an IRE system specifically developed for use in an MRI environment. The system is initially tested with a standard IRE sequence and then the interference between a clinical 3 T MRI device and the IRE system is investigated using a noise measurement and the signal-to-noise ratio (SNR) of images acquired with a gradient echo (GRE) sequence. The results show, that although the SNR of the images decrease by maximal 36 % when the IRE system is switched on, image quality does not visibly degrade. Hence, MRI-guided IRE is feasible with the proposed system.Clinical relevance— This paper demonstrates the possibility of MRI-guided IRE with only minor image degradation when the IRE system is used in parallel with MRI imaging.