A k-space sharing 3D GRASE pseudocontinuous ASL method for whole-brain resting-state functional connectivity

TY - JOUR

T1 - A k-space sharing 3D GRASE pseudocontinuous ASL method for whole-brain resting-state functional connectivity

AU - Liang, Xiaoyun

AU - Tournier, Jacques-Donald

AU - Masterton, Richard

AU - Connelly, Alan

AU - Calamante, Fernando

PY - 2012/3

Y1 - 2012/3

N2 - Magnetic resonance imaging (MRI) investigations of resting-state functional connectivity (RSFC) typically use blood oxygen level-dependent (BOLD)-weighted imaging because of its ability to provide whole-brain coverage and high temporal resolution. Single-shot 3D gradient- and spin-echo (GRASE) arterial spin labeling (ASL) offers a number of potential advantages for RSFC measurements, such as a more direct quantitative correlate of neural activity and lower variability across subjects; however, current sequences are usually not suitable for whole-brain acquisitions because of T2 decay during the long echo train. In this study, we proposed a k-space sharing 3D GRASE ASL sequence to achieve whole-brain coverage, applied it to measure RSFC on a group of healthy subjects, and compared it with BOLD data. Similar RSFC networks were estimated using both techniques, providing corroboration of the capability of our method for RSFC analysis. Furthermore, ASL data enable calculation of mean cerebral blood flow (CBF) values within the RSFC networks, thus assigning them biologically meaningful values. The inherently quantitative nature of CBF measurements should provide a more stable and interpretable biomarker in comparison to BOLD and may, therefore, be particularly useful for applications such as longitudinal studies of RSFC.

AB - Magnetic resonance imaging (MRI) investigations of resting-state functional connectivity (RSFC) typically use blood oxygen level-dependent (BOLD)-weighted imaging because of its ability to provide whole-brain coverage and high temporal resolution. Single-shot 3D gradient- and spin-echo (GRASE) arterial spin labeling (ASL) offers a number of potential advantages for RSFC measurements, such as a more direct quantitative correlate of neural activity and lower variability across subjects; however, current sequences are usually not suitable for whole-brain acquisitions because of T2 decay during the long echo train. In this study, we proposed a k-space sharing 3D GRASE ASL sequence to achieve whole-brain coverage, applied it to measure RSFC on a group of healthy subjects, and compared it with BOLD data. Similar RSFC networks were estimated using both techniques, providing corroboration of the capability of our method for RSFC analysis. Furthermore, ASL data enable calculation of mean cerebral blood flow (CBF) values within the RSFC networks, thus assigning them biologically meaningful values. The inherently quantitative nature of CBF measurements should provide a more stable and interpretable biomarker in comparison to BOLD and may, therefore, be particularly useful for applications such as longitudinal studies of RSFC.

KW - perfusion functional MRI

KW - arterial spin labeling

KW - 3D gradient- and spin-echo

KW - resting-state functional connectivity

KW - CEREBRAL-BLOOD-FLOW

KW - LABELING PERFUSION MEASUREMENTS

KW - IMAGING TECHNIQUES

KW - MRI

KW - ACTIVATION

KW - FMRI

KW - NETWORKS

KW - BOLD

KW - EFFICIENCY

KW - FREQUENCY

U2 - 10.1002/ima.22006

DO - 10.1002/ima.22006

M3 - Article

SN - 0899-9457

VL - 22

SP - 37

EP - 43

JO - INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY

JF - INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY

IS - 1

ER -