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Ultrahigh-field MRI whole-slice and localized RF field excitations using the same RF transmit array.

Tamer S Ibrahim
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Abstract

In this paper, a multiport driving mechanism is numerically implemented at ultra high-field (UHF) magnetic resonance imaging (MRI) to provide 1) homogenous whole-slice (axial, sagittal, or coronal) and 2) highly localized radio frequency (RF) field excitation within the same slices, all with the same RF transmit array (here chosen to be a standard transverse electromagnetic (TEM) resonator/coil). The method is numerically tested using a full-wave model of a TEM coil loaded with a high-resolution/18-tissue/anatomically detailed human head mesh. The proposed approach is solely based on electromagnetic and phased array antenna theories. The results demonstrate that both homogenous whole-slice as well as localized RF excitation can be achieved within any slice of the head at 7 T (298 MHz for proton imaging).

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AlgorithmsAnatomy, Cross-SectionalBrainBrain MappingComputer SimulationEquipment DesignEquipment Failure AnalysisHumansImage EnhancementImage Interpretation, Computer-AssistedImaging, Three-DimensionalMagnetic Resonance ImagingMaleModels, NeurologicalRadio WavesReproducibility of ResultsSensitivity and SpecificityTransducersEvaluation StudyJournal Article

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Tamer S Ibrahim. 2006. Ultrahigh-field MRI whole-slice and localized RF field excitations using the same RF transmit array.. https://doi.org/10.1109/tmi.2006.880666

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