Synopsis
Universally
observed cognitive decline in the elderly due to the pathological aging of the
brain will have a significant impact on public health. This
presentation will aid in understanding 1) the recent advances in the field of
aging and dementia; 2) MR methodologies that are used for the evaluation of age
and dementia related brain changes specifically due to Alzheimer’s disease
pathophysiology and cerebrovascular disease as tools for diagnosis,
prognosis, measuring disease progression, and mechanistic inferences into the disease
process in cognitive aging and dementia; and 3) open questions and directions in this
research area for MR.
TARGET AUDIENCE
Scientists and Clinicians interested in the
use of MR for measuring brain changes associated with cognitive aging and
dementia.
BACKGROUND
Universally
observed cognitive decline in the elderly due to the pathological aging of the
brain will have a significant impact on public health. Alzheimer’s disease (AD)
pathophysiology and cerebrovascular disease (CVD) are the leading causes of
age-related cognitive decline. While the hallmarks of AD are the presence of
amyloid β (Aβ) plaques and neurofibrillary tangles, the downstream effects on
neurodegeneration are the proximal cause of cognitive decline in AD dementia.
The hallmarks of CVD are the presence of microvascular changes (white matter
hyperintensities and microbleeds) and macrovascular changes (infarcts) which
are associated with significant structural and functional brain changes. Even
before the appearance of CVD, systemic vascular health has significant impact
on brain structure and function.
PURPOSE
Given
that the clinical assessment is unlikely to exactly match findings at autopsy
in every subject in aging and dementia, in-vivo imaging measures, such as MRI that reflects disease
stage and intensity have been found to be extremely useful. The value added to
clinical assessment by MRI is that it is an independent non-invasive measure of
disease in contrast to clinical diagnosis which is done on the basis of clinical
examination and neuropsychological tests. Therefore, understanding the changes
to the brain due to aging and pathology will aid in better use of MR as a tool
for diagnosis, prognosis, measuring disease progression, differential
diagnosis, and mechanistic inferences into the disease process. OUTCOMES
The learning
objectives of this talk are 1) understanding the advances in the field of aging
and dementia; 2) MR methodologies (structural MRI, T2* GRE/SWI, FLAIR, DTI,
task-free fMRI) that are used for the evaluation of age and dementia related
brain changes specifically due to Alzheimer’s disease pathophysiology and
cerebrovascular disease; and 3) open questions and directions in this research
area for MR.
Acknowledgements
The NIH for funding support.References
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