TY - JOUR
T1 - Ex vivo T2 relaxation
T2 - Associations with age-related neuropathology and cognition
AU - Dawe, Robert J.
AU - Bennett, David A.
AU - Schneider, Julie A.
AU - Leurgans, Sue E.
AU - Kotrotsou, Aikaterini
AU - Boyle, Patricia A.
AU - Arfanakis, Konstantinos
N1 - Funding Information:
This work was supported by the National Institute on Aging (grant numbers P30 AG10161 , R01 AG15819 , and R01 AG17917 ) and by the Alzheimer's Disease Research Fund of the Illinois Department of Public Health . The authors thank the participants of the Rush Memory and Aging Project and the Religious Orders Study. They also thank the reviewers of this manuscript for their valuable comments.
PY - 2014/7
Y1 - 2014/7
N2 - The transverse relaxation time constant, T2, is sensitive to brain tissue's free water content and the presence of paramagnetic materials such as iron. In this study, exvivo magnetic resonance imaging was used to investigate alterations in T2 related to Alzheimer's disease (AD) pathology and other types of neuropathology common in old age, as well as the relationship between T2 alterations and cognition. Cerebral hemispheres were obtained from 371 deceased older adults. Using fast spin-echo imaging with multiple echo times, T2 maps were produced and warped to a study-specific template. Hemispheres underwent neuropathologic examination for identification of AD pathology and other common age-related neuropathologies. Voxelwise linear regression was carried out to detect regions of pathology-related T2 alterations and, in separate analyses, regions in which T2 alterations were linked to antemortem cognitive performance. AD pathology was associated with T2 prolongation in white matter of all lobes and T2 shortening in the basal ganglia and insula. Gross infarcts were associated with T2 prolongation in white matter of all lobes, and in the thalamus and basal ganglia. Hippocampal sclerosis was associated with T2 prolongation in the hippocampus and white matter of the temporal lobe. After controlling for neuropathology, T2 prolongation in the frontal lobe white matter was associated with lower performance in the episodic, semantic, and working memory domains. In addition, voxelwise analysis of invivo and exvivo T2 values indicated a positive relationship between the two, though further investigation is necessary to accurately translate findings of the present study to the invivo case.
AB - The transverse relaxation time constant, T2, is sensitive to brain tissue's free water content and the presence of paramagnetic materials such as iron. In this study, exvivo magnetic resonance imaging was used to investigate alterations in T2 related to Alzheimer's disease (AD) pathology and other types of neuropathology common in old age, as well as the relationship between T2 alterations and cognition. Cerebral hemispheres were obtained from 371 deceased older adults. Using fast spin-echo imaging with multiple echo times, T2 maps were produced and warped to a study-specific template. Hemispheres underwent neuropathologic examination for identification of AD pathology and other common age-related neuropathologies. Voxelwise linear regression was carried out to detect regions of pathology-related T2 alterations and, in separate analyses, regions in which T2 alterations were linked to antemortem cognitive performance. AD pathology was associated with T2 prolongation in white matter of all lobes and T2 shortening in the basal ganglia and insula. Gross infarcts were associated with T2 prolongation in white matter of all lobes, and in the thalamus and basal ganglia. Hippocampal sclerosis was associated with T2 prolongation in the hippocampus and white matter of the temporal lobe. After controlling for neuropathology, T2 prolongation in the frontal lobe white matter was associated with lower performance in the episodic, semantic, and working memory domains. In addition, voxelwise analysis of invivo and exvivo T2 values indicated a positive relationship between the two, though further investigation is necessary to accurately translate findings of the present study to the invivo case.
KW - Cognition
KW - Gross infarct
KW - Hippocampal sclerosis
KW - MRI
KW - Neuroimaging
KW - Voxelwise
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U2 - 10.1016/j.neurobiolaging.2014.01.144
DO - 10.1016/j.neurobiolaging.2014.01.144
M3 - Article
C2 - 24582637
AN - SCOPUS:84903362501
SN - 0197-4580
VL - 35
SP - 1549
EP - 1561
JO - Neurobiology of Aging
JF - Neurobiology of Aging
IS - 7
ER -