Fast B1 field localisation in high-field MRI systems
نویسنده
چکیده
In high-magnetic magnetic resonance imaging (MRI) systems (7 T and above), the radio frequency (RF) field shows greater inhomogeneity compared with clinical MRI systems (1.5 and 3.0 T). In multichannel RF coils, driving each coil element with convex optimisation can reduce non-uniformity of the RF field in a region of interest. In this Letter, a periodic compressed method (PCM) and a PCM after averaging are proposed in order to reduce RF coil control time at high fields. Simulation results were obtained using a human head model in 7 and 9.4 T systems, and the results are discussed in detail.
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