Abstract
The basic principles of the design of spatially selective RF pulses are described, and their analogy with MR image acquisition and reconstruction is shown. The paper focuses on RF-pulse design and imaging schemes in which spiral k-space trajectories are used. The sensitivity of RF excitation to gradient-system imperfections and to spatially varying off-resonance are analyzed, and suitable measures of correction are discussed. The spatial resolution obtainable with selective RF pulses and the consequences of the linearity of the pulse-design problem are examined. Phantom experiments showing the performance of multidimensional spatially selective RF pulses further illustrate the analogy with MR image acquisition.
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Börnert, P., Aldefeld, B. On spatially selective RF excitation and its analogy with spiral MR image acquisition. MAGMA 7, 166–178 (1998). https://doi.org/10.1007/BF02591334
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DOI: https://doi.org/10.1007/BF02591334