Microstructural white matter changes in normal aging: a diffusion tensor imaging study with higher-order polynomial regression models.
Diffusion tensor imaging (DTI) has already proven to be a valuable tool when investigating both global and regional microstructural white matter (WM) brain changes in the human aging process. Although subject to many criticisms, voxel-based analysis is currently one of the most common and preferred approaches in such DTI aging studies. In this context, voxel-based DTI analyses have assumed a 'linear' correlation when finding the significant brain regions that relate age with a particular diffusion measure of interest. Recent literature, however, has clearly demonstrated 'non-linear' relationships between age and diffusion metrics by using region-of-interest and tractography-based approaches. In this work, we incorporated polynomial regression models in the voxel-based DTI analysis framework to assess age-related changes in WM diffusion properties (fractional anisotropy and axial, transverse, and mean diffusivity) in a large cohort of 346 subjects (25 to 81 years old). Our novel approach clearly demonstrates that voxel-based DTI analyses can greatly benefit from incorporating higher-order regression models when investigating potential relationships between aging and diffusion properties.
Hsu
Jung-Lung
JL
Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan. tulu@ms36.hinet.net
Van Hecke
Wim
W
Bai
Chyi-Huey
CH
Lee
Cheng-Hui
CH
Tsai
Yuh-Feng
YF
Chiu
Hou-Chang
HC
Jaw
Fu-Shan
FS
Hsu
Chien-Yeh
CY
Leu
Jyu-Gang
JG
Chen
Wei-Hung
WH
Leemans
Alexander
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000465:Algorithms; D001921:Brain / Q000648:ultrastructure*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012044:Regression Analysis