Age-related microstructural differences quantified using myelin water imaging and advanced diffusion MRI

NEUROBIOLOGY OF AGING

卷:36

Article

Billiet, Thibo^1,2,3,4  Vandenbulcke, Mathieu^4,5  Maedler, Burkhard^6,7  Peeters, Ronald^2,4  Dhollander, Thijs^3,8  Zhang, Hui^9,10  Deprez, Sabine^1,2,3,4  Van den Bergh, Bea R. H.^11,12  Sunaert, Stefan^1,2,3,4  Emsell, Louise^1,2,3,4,5 

[1] Katholieke Univ Leuven, Dept Imaging & Pathol, Translat MRI, Leuven, Belgium

[2] Univ Hosp Leuven, Dept Radiol, B-3000 Leuven, Belgium

[3] MIRC, Leuven, Belgium

[4] Leuven Res Inst Neurosci & Dis LIND, Leuven, Belgium

[5] Katholieke Univ Leuven, Dept Old Age Psychiat, Leuven, Belgium

[6] Philips Healthcare, Hamburg, Germany

[7] Univ Bonn, Med Ctr, Dept Neurosurg, Bonn, Germany

[8] Florey Inst Neurosci & Mental Hlth, Melbourne, Vic, Australia

[9] UCL, Dept Comp Sci, London, England

[10] UCL, Ctr Med Image Comp, London, England

[11] Tilburg Univ, Dept Dev Psychol, NL-5000 LE Tilburg, Netherlands

[12] Katholieke Univ Leuven, Dept Psychol, Leuven, Belgium

关键词: Aging;    Relaxometry;    Myelin water imaging;    Diffusion MRI;    Healthy;    Kurtosis;   

DOI  :  10.1016/j.neurobiolaging.2015.02.029

来源: Elsevier

【 摘 要 】

Age-related microstructural differences have been detected using diffusion tensor imaging (DTI). Although DTI is sensitive to the effects of aging, it is not specific to any underlying biological mechanism, including demyelination. Combining multiexponential T2 relaxation (MET2) and multishell diffusion MRI (dMRI) techniques may elucidate such processes. Multishell dMRI and MET2 data were acquired from 59 healthy participants aged 17-70 years. Whole-brain and regional age-associated correlations of measures related to multiple dMRI models (DTI, diffusion kurtosis imaging [DKI], neurite orientation dispersion and density imaging [NODDI]) and myelin-sensitive MET2 metrics were assessed. DTI and NODDI revealed widespread increases in isotropic diffusivity with increasing age. In frontal white matter, fractional anisotropy linearly decreased with age, paralleled by increased neurite dispersion and no difference in myelin water fraction. DKI measures and neurite density correlated well with myelin water fraction and intracellular and extracellular water fraction. DTI estimates remain among the most sensitive markers for age-related alterations in white matter. NODDI, DKI, and MET2 indicate that the initial decrease in frontal fractional anisotropy may be due to increased axonal dispersion rather than demyelination. (C) 2015 Elsevier Inc. All rights reserved.

【 授权许可】

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