Related Experiment Video
Updated: May 8, 2026
05:17
Hybrid PET/MRI Imaging of Alzheimer's Disease Based on 18F-AV-1451
Published on: April 18, 2025
Abnormal amyloid PET usually represents intermediate/high Alzheimer's disease neuropathologic change
Brian J Burkett1, Heather J Wiste2, Derek R Johnson1
1Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
Summary
A positive amyloid PET scan rarely indicates not/low Alzheimer's disease neuropathologic change (ADNC). Even over 10 years after a positive scan, not/low ADNC is an uncommon autopsy finding.
Area of Science:
- Neurology
- Neuroimaging
- Pathology
Background:
- Alzheimer's disease neuropathologic change (ADNC) classification distinguishes between not/low and intermediate/high levels of brain pathology.
- Amyloid positron emission tomography (PET) scans are used to detect amyloid plaques, a hallmark of Alzheimer's disease.
Purpose of the Study:
- To determine the frequency of not/low ADNC in individuals with positive amyloid PET scans.
- To investigate if not/low ADNC can be present more than 10 years after a positive amyloid PET scan.
Main Methods:
- Individuals with positive amyloid PET scans were analyzed.
- Autopsy ADNC levels were assessed and grouped by time from positive amyloid PET to death (<5 years, 5 to <10 years, 10+ years).
Main Results:
- The majority of individuals (90%) with a positive amyloid PET scan showed intermediate/high ADNC at autopsy.
- In the group with 10+ years between a positive amyloid PET and death (n=39), only 8% (3/39) had not/low ADNC.
Conclusions:
- Not/low ADNC is infrequently associated with positive amyloid PET scans.
- While rare, a positive amyloid PET scan can represent an indolent neuropathologic state even over 10 years post-scan.
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