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PT  - JOURNAL ARTICLE
AU  - Spilt, Aart
AU  - Geeraedts, Tychon
AU  - de Craen, Anton J. M.
AU  - Westendorp, Rudi G. J.
AU  - Blauw, Gerard J.
AU  - van Buchem, Mark A.
TI  - Age-Related Changes in Normal-Appearing Brain Tissue and White Matter Hyperintensities: More of the Same or Something Else?
DP  - 2005 Apr 01
TA  - American Journal of Neuroradiology
PG  - 725--729
VI  - 26
IP  - 4
4099  - http://www.ajnr.org/content/26/4/725.short
4100  - http://www.ajnr.org/content/26/4/725.full
SO  - Am. J. Neuroradiol.2005 Apr 01; 26
AB  - BACKGROUND AND PURPOSE: Cerebral white matter (WM) hyperintensities are a frequent finding in elderly people, and lowering of cerebral magnetization transfer ratio (MTR) has been observed. The aim of this study was to assess the relationship between age-related WM hyperintensities and MTR changes in the brain.METHODS: We performed MR imaging in a group of young subjects, a group of elderly individuals with minimal WM hyperintensities, and a group of elderly individuals with abundant WM hyperintensities. In addition, we performed volumetric MTR analysis of the whole brain and of the normal-appearing WM (NAWM) in these groups.RESULTS: Volumetric MTR parameters differed between elderly and young patients. Mean MTR ± standard error of the mean (SEM) was 34.0% ± 0.12% in the young, 33.0% ± 0.08% in the elderly with minimal WM hyperintensities, 32.8% ± 0.09%) in the group with abundant WM hyperintensities. Peak height (number of voxels ± SEM) was 122 ± 1.2 in the young, 99 ± 1.5 in the elderly with minimal WM hyperintensities, and 98 ± 1.6 in the group with abundant WM hyperintensities. Mean MTR of NAWM was lower in the elderly compared with the young (36.7% ± 0.12%) but did not differ between subjects with minimal (36.0% ± 0.11%) and those with abundant WM hyperintensities (35.9% ± 0.13%).CONCLUSION: Our results show that aging gives rise to changes in normal-appearing brain tissue. These changes, which can be detected on magnetization transfer imaging, seem to have no relationship with age-related WM hyperintensities and might have a different etiology.