Design of a Four-Channel Surface Receiver Coil Array Without Preamplifiers for the Decoupling Between Elements: Validation for High-Resolution Rat Knee MR Imaging

International audienceIn Magnetic Resonance Imaging (MRI), multi-channel coil arrays are increasingly being used to improve Signal-to-Noise Ratio (SNR) in order to increase spatial and/or temporal image resolution. Recent decoupling technique allows conception of two-channel surface transceiver coil arrays; this technique based on common conductor does not require additional preamplifier for the decoupling between elements. In this case the coil array loops are directly connected to the independent transmit/receive switches and preamplifiers of the MR system. Using this common conductor decoupling technique, a topology of a four-channel coil array was developed and described in this paper. A four-channel surface receiver coil array was designed to perform the simultaneous acquisition of both rat knee joints at 7T. Without the use of additional preamplifiers, a good decoupling between channels was obtained and very high spatial resolution 3D images with a voxel size of 49 × 49 × 98 µm 3 were achieved in 1h22min scan time. Acquisitions allowed the quantification of cartilage morphological parameters such as thickness and volum