Mapping resting-state functional connectivity using perfusion MRI.
Neuroimage
; 40(4): 1595-605, 2008 May 01.
Article
in En
| MEDLINE
| ID: mdl-18314354
ABSTRACT
Resting-state, low-frequency (<0.08 Hz) fluctuations of blood oxygenation level-dependent (BOLD) magnetic resonance signal have been shown to exhibit high correlation among functionally connected regions. However, correlations of cerebral blood flow (CBF) fluctuations during the resting state have not been extensively studied. The main challenges of using arterial spin labeling perfusion magnetic resonance imaging to detect CBF fluctuations are low sensitivity, low temporal resolution, and contamination from BOLD. This work demonstrates CBF-based quantitative functional connectivity mapping by combining continuous arterial spin labeling (CASL) with a neck labeling coil and a multi-channel receiver coil to achieve high perfusion sensitivity. In order to reduce BOLD contamination, the CBF signal was extracted from the CASL signal time course by high frequency filtering. This processing strategy is compatible with sinc interpolation for reducing the timing mismatch between control and label images and has the flexibility of choosing an optimal filter cutoff frequency to minimize BOLD fluctuations. Most subjects studied showed high CBF correlation in bilateral sensorimotor areas with good suppression of BOLD contamination. Root-mean-square CBF fluctuation contributing to bilateral correlation was estimated to be 29+/-19% (N=13) of the baseline perfusion, while BOLD fluctuation was 0.26+/-0.14% of the mean intensity (at 3 T and 12.5 ms echo time).
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Brain Mapping
/
Magnetic Resonance Imaging
/
Cerebrovascular Circulation
Limits:
Adult
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Neuroimage
Journal subject:
DIAGNOSTICO POR IMAGEM
Year:
2008
Document type:
Article
Affiliation country:
United States