Multivariate statistical mapping of spectroscopic imaging data.
For magnetic resonance spectroscopic imaging studies of the brain, it is important to measure the distribution of metabolites in a regionally unbiased way; that is, without restrictions to a priori defined regions of interest. Since magnetic resonance spectroscopic imaging provides measures of multiple metabolites simultaneously at each voxel, there is furthermore great interest in utilizing the multidimensional nature of magnetic resonance spectroscopic imaging for gains in statistical power. Voxelwise multivariate statistical mapping is expected to address both of these issues, but it has not been previously employed for spectroscopic imaging (SI) studies of brain. The aims of this study were to (1) develop and validate multivariate voxel-based statistical mapping for magnetic resonance spectroscopic imaging and (2) demonstrate that multivariate tests can be more powerful than univariate tests in identifying patterns of altered brain metabolism. Specifically, we compared multivariate to univariate tests in identifying known regional patterns in simulated data and regional patterns of metabolite alterations due to amyotrophic lateral sclerosis, a devastating brain disease of the motor neurons.
Young
Karl
K
Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, California 94121, USA. karl.young@ucsf.edu
Govind
Varan
V
Sharma
Khema
K
Studholme
Colin
C
Maudsley
Andrew A
AA
Schuff
Norbert
N
D000328:Adult; D000465:Algorithms; D000690:Amyotrophic Lateral Sclerosis / Q000378:metabolism*; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001921:Brain / Q000378:metabolism*; D002794:Choline / Q000032:analysis*; D003404:Creatinine / Q000032:analysis*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D015415:Biomarkers; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003404:Creatinine; D002794:Choline