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Abstract #2610

Impact of Number of Tx Channels for RF Shimming an in vivo Study

Alexander Childs1, Shaihan J. Malik1, Declan P. O'Regan1, Joseph V. Hajnal1

1Robert Steiner MRI Unit,Imaging Sciences Department, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College London, London, United Kingdom

Multi-channel transmission allows individualised subject specific RF shimming to be used to mitigate B1+ inhomogeneity and improve image signal and contrast uniformity. Using a whole body 3T system with 8 transmit channels, we have performed a systematic study in vivo of RF shim performance in both the pelvis and thighs for coil configurations with 1, 2, 4 or 8 independent channels. As the number of channels was increased, B1+ homogeneity progressively and significantly increased, while total RF power requirements for the same homogeneity systematically decreased. T1w images also showed perceptible progressive improvement with number of channels used for shimming.

Keywords

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