Iterative Tuning of System Delay and Phase Correction for Echo-Planar Imaging
نویسنده
چکیده
Introduction Echo-planar imaging (EPI) suffers from ghosting artifacts if the sample positions in k-space are not accurately known. Many effects lead to a distortion of the ideal gradient waveforms and cause differences in the sample positions for echoes acquired with positive and negative readout gradient polarity. Various methods have been developed to compensate for them, which rely on either additional calibration data or on heuristic criteria in image space [1]. In this work, a new, iterative method of the first kind is presented to improve tolerance to a badly adjusted system delay.
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