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Hybrid PET/MRI Imaging of Alzheimer's Disease Based on 18F-AV-1451
Published on: April 18, 2025
Amyloid imaging in mild cognitive impairment subtypes.
David A Wolk1, Julie C Price, Judy A Saxton
1Alzheimer's Disease Research Center, University of Pittsburgh, Pittsburgh, PA 19104, USA. david.wolk@uphs.upenn.edu
Annals of Neurology
|May 29, 2009
Summary
Amyloid imaging with Pittsburgh Compound B (PiB) identifies Alzheimer's disease (AD) pathology in mild cognitive impairment (MCI) subtypes. Amyloid-positive MCI patients show higher conversion rates to AD, indicating PiB's role in predicting disease progression.
Area of Science:
- Neurology
- Neuroimaging
- Alzheimer's Disease Research
Background:
- Mild cognitive impairment (MCI) encompasses various subtypes, some progressing to Alzheimer's disease (AD).
- Early detection of AD pathology in MCI is crucial for timely intervention and disease management.
Purpose of the Study:
- To utilize Pittsburgh Compound B (PiB) amyloid imaging to detect AD pathology across different MCI subtypes.
- To correlate PiB retention with early AD markers and predict longitudinal outcomes in MCI patients.
Main Methods:
- Twenty-six MCI patients (amnestic and nonamnestic subtypes) underwent PiB positron emission tomography (PET) imaging.
- Clinical follow-up was conducted for 23 patients to assess conversion to AD.
Main Results:
- Over half (54%) of MCI patients were amyloid-positive, indicating significant PiB retention across all subtypes.
- Amyloid-positive MCI patients exhibited poorer episodic memory and medial temporal atrophy compared to amyloid-negative counterparts.
- Five amyloid-positive MCI patients converted to AD, while no amyloid-negative patients converted, and some reverted to normal cognition.
Conclusions:
- Amyloid-positive status in MCI, identified by PiB imaging, suggests early AD pathology and predicts progression to clinical AD.
- Amyloid imaging may aid in selecting MCI patients for disease-specific therapies.
- A substantial proportion of MCI patients across subtypes are likely to develop AD over time.
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