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Generalized Psychophysiological Interaction (PPI) Analysis of Memory Related Connectivity in Individuals at Genetic Risk for Alzheimer's Disease
Published on: November 14, 2017
Hippocampal shape analysis in Alzheimer's disease: a population-based study
1Department of Preventive Medicine and Biometrics, Uniformed Services University, Bethesda, MD 20814, USA. ascher@usuhs.mil
Neuroimage
|April 17, 2007
Summary
Alzheimer's disease (AD) is associated with significant hippocampal atrophy, particularly in the CA1 region. Structural MRI reveals smaller hippocampal volumes and distinct shape differences in elderly men with AD compared to controls.
Area of Science:
- Neuroimaging
- Gerontology
- Alzheimer's Disease Research
Background:
- Hippocampal atrophy, especially in the CA1 region, is a potential biomarker for Alzheimer's disease (AD) risk.
- Distinguishing AD-related hippocampal changes from normal aging is crucial for clinical diagnosis and research.
- This study investigates in vivo hippocampal structural differences in elderly men with incident AD.
Purpose of the Study:
- To model and compare hippocampal size and regional shape variations.
- To differentiate between elderly men with incident Alzheimer's disease and a non-demented comparison group.
- To identify potential imaging biomarkers for AD using structural MRI.
Main Methods:
- Utilized structural MRI on Japanese-American men from the Honolulu Asia Aging Study (HAAS).
- Compared a cohort of incident Alzheimer's disease (AD) cases (n=24) with non-demented controls (n=102).
- Employed 3D structural shape analysis to assess regional hippocampal diameter variations.
Main Results:
- Mean total hippocampal volume was 11.5% smaller in AD cases versus controls.
- Shape analysis indicated regional differences, more pronounced in the hippocampal body (including CA1) and the left hippocampus.
- Observed surface changes intersected key regions like the CA1, subiculum, and dentate gyrus-hilar region.
Conclusions:
- Hippocampal atrophy and specific regional shape alterations are evident in elderly men with incident Alzheimer's disease.
- These findings support the use of hippocampal structural MRI as a potential biomarker for AD.
- Further research can refine these imaging techniques for earlier and more accurate AD diagnosis.
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