摘要
Purpose: One of the technical advantages of functional magnetic resonance imaging (fMRI) is its precise localization of changes from neuronal activities. While current practice of fMRI acquisition at voxel size around 3 × 3 × 3 mm3 achieves satisfactory results in studies of basic brain functions, higher spatial resolution is required in order to resolve finer cortical structures. This study investigated spatial resolution effects on brain fMRI experiments using balanced steady-state free precession (bSSFP) imaging with 0.37 mm3 voxel volume at 3.0 T. Methods: In fMRI experiments, full and unilateral visual field 5 Hz flashing checkerboard stimulations were given to healthy subjects. The bSSFP imaging experiments were performed at three different frequency offsets to widen the coverage, with functional activations in the primary visual cortex analyzed using the general linear model. Variations of the spatial resolution were achieved by removing outer k-space data components. Results: Results show that a reduction in voxel volume from 3.44 × 3.44 × 2 mm3 to 0.43 × 0.43 × 2 mm 3 has resulted in an increase of the functional activation signals from (7.7 ± 1.7)% to (20.9 ± 2.0)% at 3.0 T, despite of the threefold SNR decreases in the original images, leading to nearly invariant functional contrast-to-noise ratios (fCNR) even at high spatial resolution. Activation signals aligning nicely with gray matter sulci at high spatial resolution would, on the other hand, have possibly been mistaken as noise at low spatial resolution. Conclusions: It is concluded that the bSSFP sequence is a plausible technique for fMRI investigations at submillimeter voxel widths without compromising fCNR. The reduction of partial volume averaging with nonactivated brain tissues to retain fCNR is uniquely suitable for high spatial resolution applications such as the resolving of columnar organization in the brain.
| 原文 | 英語 |
|---|---|
| 文章編號 | 122304 |
| 期刊 | Medical Physics |
| 卷 | 40 |
| 發行號 | 12 |
| DOIs | |
| 出版狀態 | 已發佈 - 十二月 2013 |
指紋
ASJC Scopus subject areas
- Biophysics
- Radiology Nuclear Medicine and imaging
引用此文
High spatial resolution brain functional MRI using submillimeter balanced steady-state free precession acquisition. / Wu, Pei Hsin; Tsai, Ping Huei; Wu, Ming Long; Chuang, Tzu Chao; Shih, Yi Yu; Chung, Hsiao Wen; Huang, Teng Yi.
於: Medical Physics, 卷 40, 編號 12, 122304, 12.2013.研究成果: 雜誌貢獻 › 文章
}
TY - JOUR
T1 - High spatial resolution brain functional MRI using submillimeter balanced steady-state free precession acquisition
AU - Wu, Pei Hsin
AU - Tsai, Ping Huei
AU - Wu, Ming Long
AU - Chuang, Tzu Chao
AU - Shih, Yi Yu
AU - Chung, Hsiao Wen
AU - Huang, Teng Yi
PY - 2013/12
Y1 - 2013/12
N2 - Purpose: One of the technical advantages of functional magnetic resonance imaging (fMRI) is its precise localization of changes from neuronal activities. While current practice of fMRI acquisition at voxel size around 3 × 3 × 3 mm3 achieves satisfactory results in studies of basic brain functions, higher spatial resolution is required in order to resolve finer cortical structures. This study investigated spatial resolution effects on brain fMRI experiments using balanced steady-state free precession (bSSFP) imaging with 0.37 mm3 voxel volume at 3.0 T. Methods: In fMRI experiments, full and unilateral visual field 5 Hz flashing checkerboard stimulations were given to healthy subjects. The bSSFP imaging experiments were performed at three different frequency offsets to widen the coverage, with functional activations in the primary visual cortex analyzed using the general linear model. Variations of the spatial resolution were achieved by removing outer k-space data components. Results: Results show that a reduction in voxel volume from 3.44 × 3.44 × 2 mm3 to 0.43 × 0.43 × 2 mm 3 has resulted in an increase of the functional activation signals from (7.7 ± 1.7)% to (20.9 ± 2.0)% at 3.0 T, despite of the threefold SNR decreases in the original images, leading to nearly invariant functional contrast-to-noise ratios (fCNR) even at high spatial resolution. Activation signals aligning nicely with gray matter sulci at high spatial resolution would, on the other hand, have possibly been mistaken as noise at low spatial resolution. Conclusions: It is concluded that the bSSFP sequence is a plausible technique for fMRI investigations at submillimeter voxel widths without compromising fCNR. The reduction of partial volume averaging with nonactivated brain tissues to retain fCNR is uniquely suitable for high spatial resolution applications such as the resolving of columnar organization in the brain.
AB - Purpose: One of the technical advantages of functional magnetic resonance imaging (fMRI) is its precise localization of changes from neuronal activities. While current practice of fMRI acquisition at voxel size around 3 × 3 × 3 mm3 achieves satisfactory results in studies of basic brain functions, higher spatial resolution is required in order to resolve finer cortical structures. This study investigated spatial resolution effects on brain fMRI experiments using balanced steady-state free precession (bSSFP) imaging with 0.37 mm3 voxel volume at 3.0 T. Methods: In fMRI experiments, full and unilateral visual field 5 Hz flashing checkerboard stimulations were given to healthy subjects. The bSSFP imaging experiments were performed at three different frequency offsets to widen the coverage, with functional activations in the primary visual cortex analyzed using the general linear model. Variations of the spatial resolution were achieved by removing outer k-space data components. Results: Results show that a reduction in voxel volume from 3.44 × 3.44 × 2 mm3 to 0.43 × 0.43 × 2 mm 3 has resulted in an increase of the functional activation signals from (7.7 ± 1.7)% to (20.9 ± 2.0)% at 3.0 T, despite of the threefold SNR decreases in the original images, leading to nearly invariant functional contrast-to-noise ratios (fCNR) even at high spatial resolution. Activation signals aligning nicely with gray matter sulci at high spatial resolution would, on the other hand, have possibly been mistaken as noise at low spatial resolution. Conclusions: It is concluded that the bSSFP sequence is a plausible technique for fMRI investigations at submillimeter voxel widths without compromising fCNR. The reduction of partial volume averaging with nonactivated brain tissues to retain fCNR is uniquely suitable for high spatial resolution applications such as the resolving of columnar organization in the brain.
KW - Balanced steady-state free precession (bssfp)
KW - Functional magnetic resonance imaging (fmri)
KW - High resolution
UR - http://www.scopus.com/inward/record.url?scp=84890058835&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84890058835&partnerID=8YFLogxK
U2 - 10.1118/1.4828789
DO - 10.1118/1.4828789
M3 - Article
C2 - 24320535
AN - SCOPUS:84890058835
VL - 40
JO - Medical Physics
JF - Medical Physics
SN - 0094-2405
IS - 12
M1 - 122304
ER -