Correction of vibration artifacts in DTI using phase-encoding reversal (COVIPER)

TY - JOUR

T1 - Correction of vibration artifacts in DTI using phase-encoding reversal (COVIPER)

AU - Mohammadi, Siawoosh

AU - Nagy, Zoltan

AU - Hutton, Chloe

AU - Josephs, Oliver

AU - Weiskopf, Nikolaus

N1 - Copyright © 2011 Wiley Periodicals, Inc.

PY - 2012/9/1

Y1 - 2012/9/1

N2 - Diffusion tensor imaging is widely used in research and clinical applications, but still suffers from substantial artifacts. Here, we focus on vibrations induced by strong diffusion gradients in diffusion tensor imaging, causing an echo shift in k-space and consequential signal-loss. We refined the model of vibration-induced echo shifts, showing that asymmetric k-space coverage in widely used Partial Fourier acquisitions results in locally differing signal loss in images acquired with reversed phase encoding direction (blip-up/blip-down). We implemented a correction of vibration artifacts in diffusion tensor imaging using phase-encoding reversal (COVIPER) by combining blip-up and blip-down images, each weighted by a function of its local tensor-fit error. COVIPER was validated against low vibration reference data, resulting in an error reduction of about 72% in fractional anisotropy maps. COVIPER can be combined with other corrections based on phase encoding reversal, providing a comprehensive correction for eddy currents, susceptibility-related distortions and vibration artifact reduction.

AB - Diffusion tensor imaging is widely used in research and clinical applications, but still suffers from substantial artifacts. Here, we focus on vibrations induced by strong diffusion gradients in diffusion tensor imaging, causing an echo shift in k-space and consequential signal-loss. We refined the model of vibration-induced echo shifts, showing that asymmetric k-space coverage in widely used Partial Fourier acquisitions results in locally differing signal loss in images acquired with reversed phase encoding direction (blip-up/blip-down). We implemented a correction of vibration artifacts in diffusion tensor imaging using phase-encoding reversal (COVIPER) by combining blip-up and blip-down images, each weighted by a function of its local tensor-fit error. COVIPER was validated against low vibration reference data, resulting in an error reduction of about 72% in fractional anisotropy maps. COVIPER can be combined with other corrections based on phase encoding reversal, providing a comprehensive correction for eddy currents, susceptibility-related distortions and vibration artifact reduction.

KW - Algorithms

KW - Artifacts

KW - Brain

KW - Brain Mapping

KW - Diffusion Magnetic Resonance Imaging

KW - Image Enhancement

KW - Image Interpretation, Computer-Assisted

KW - Numerical Analysis, Computer-Assisted

KW - Reproducibility of Results

KW - Sensitivity and Specificity

KW - Signal Processing, Computer-Assisted

KW - Vibration

U2 - 10.1002/mrm.23308

DO - 10.1002/mrm.23308

M3 - SCORING: Journal article

C2 - 22213396

VL - 68

SP - 882

EP - 889

JO - MAGN RESON MED

JF - MAGN RESON MED

SN - 0740-3194

IS - 3

ER -