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A B(0) shift correction method based on edge RMS reduction for EPI fMRI.

P V Kochunov·H L Liu·T Andrews·J H Gao·P T Fox·J L Lancaster
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Abstract

Shifting of echoplanar images (EPI) in the phase-encoding direction during functional magnetic resonance imaging (fMRI) experiments can be observed due to B(0) drift. These shifts can cause artifacts in functional activation maps that can be corrected using a navigator echo (NE) technique, but the NE correction requires pulse sequence modifications not available on many clinical systems. A fast, postprocessing correction method based on edge root-mean-square error reduction (ERMSR) is introduced and shown to provide an equivalent correction. J. Magn. Reson. Imaging 2000;12:956-959.

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ArtifactsBrainEcho-Planar ImagingHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingMotor ActivityPhantoms, ImagingSensitivity and SpecificityJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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P V Kochunov, H L Liu, T Andrews, J H Gao, P T Fox, J L Lancaster. 2000. A B(0) shift correction method based on edge RMS reduction for EPI fMRI.. https://doi.org/10.1002/1522-2586(200012)12%3A6%3C956%3A%3Aaid-jmri21%3E3.0.co%3B2-5

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