MREIT with SENSE acceleration using a dedicated RF coil design.

We have adapted a SENSE-accelerated imaging technique to magnetic resonance electrical impedance tomography (MREIT) in order to acquire data faster or improve spatial resolution without increasing the data acquisition time. We also designed and optimized an eight-channel, dedicated phased array coil for this application. The RF coil was designed as two planar arrays so that the open sides could accommodate the MREIT electrodes. A quasi-intrinsic decoupling scheme was used to minimize couplings between coil elements, and a restricted geometry optimization was applied to achieve high and uniform SNR within a given coil geometry and animal size. The impact of variability in the size of animals was also investigated in the optimization. This coil geometry provided approximately three times higher SNR at the center of a phantom when compared to a transmit/receive birdcage coil designed for MREIT of small animals. Therefore, the SNR was superior to the data acquired with volume coils even with three times SENSE acceleration. Both magnitude images and MREIT data were acquired from phantoms with and without SENSE acceleration, and the results were compared. The phantom studies demonstrated that conductivity maps can be reconstructed from MREIT data acquired with three times SENSE acceleration and that no discernible artifacts were observed when accelerated data acquisition was compared to non-accelerated data.