A B(0) shift correction method based on edge RMS reduction for EPI fMRI.
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.
Kochunov
P V
PV
Research Imaging Center, The University of Texas Health Science Center, San Antonio, Texas 78284, USA.
Liu
H L
HL
Andrews
T
T
Gao
J H
JH
Fox
P T
PT
Lancaster
J L
JL
D016477:Artifacts; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology; D017352:Echo-Planar Imaging / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009043:Motor Activity / Q000502:physiology; D019047:Phantoms, Imaging; D012680:Sensitivity and Specificity