Brain Scan Technique Spots Alzheimer’s
Brain Imaging Model Distinguishes Alzheimer’s Disease From Other Types of Dementia
WebMD News Archive
March 26, 2008 -- A computer-assisted imaging technique that measures sugar
metabolism within a critical area of the brain could
hold the key to the early diagnosis of Alzheimer's disease and other dementias.
Researchers say that the technique was accurate 94% of the time in
distinguishing Alzheimer's disease from other dementias in a newly reported
study published in the March issue of the Journal of Nuclear
It was also able to identify brain patterns associated with very early
cognitive decline, raising hopes that the imaging model might lead to earlier
diagnosis and better outcomes among patients with Alzheimer's and other
dementias, says study researcher Lisa Mosconi, PhD.
"Because the incidence of (Alzheimer's and related disorders) is
expected to increase dramatically as the baby boomer generation ages, accurate
diagnosis is extremely important -- particularly at the early and mild stages
of dementia when lifestyle changes and therapeutic
interventions would be most effective," Mosconi says.
Diagnosing Alzheimer's Disease
Mosconi and colleague Mony de Leon, EdD, both of New York University's
Center for Brain Health, developed the brain scan-based computer program after
identifying key changes in the part of the brain known as the hippocampus early
in the course of Alzheimer's disease.
Specifically, they found that the hippocampus, which is associated with
learning and memory, metabolizes glucose less efficiently as dementia
progresses. Glucose is the fuel that allows the brain to function properly.
Using positron emission tomography (PET), the researchers were able to
highlight glucose consumption patterns within the hippocampus and identify
specific images associated with normal brain function, mild cognitive
impairment, and different types of dementia, including Alzheimer's.
Their latest study included 548 people examined at seven separate centers
who were mostly in their 60s and 70s. The participants had either no evidence
of cognitive decline, mild cognitive impairment, Alzheimer's disease, or
dementia due to other causes, confirmed through a battery of neurological and
Each patient was injected with the radioactive isotope FDG, which mimicked
glucose once it entered the body. After about 30 minutes researchers began
taking pictures of the brain using PET imaging, and the images were later
analyzed using the computer program developed at NYU.