MRI Scans Could Detect Alzheimer's Early

By Elizabeth Agnvall, October 8, 2014 05:48 PM

An MRI scan can detect signs of cognitive decline in the brain before symptoms of memory loss appear, according to a new study published in the online journal Radiology. This new use of a well-known technique has the potential to be used in the very early diagnosis of Alzheimer’s disease.

Researchers in Switzerland gave MRI brain scans to 148 healthy older men and women — average age, 76 — as well as 65 people with mild cognitive impairment. The researchers then gave the participants psychological assessments and a battery of tests to determine mental abilities. The researchers found that those who showed reduced blood flow in an area of the brain linked to attention, memory and “sense of self” were more likely to show declines in memory 18 months later. The MRI scans of the patients who already had memory problems also showed reduced blood flow to this area of the brain, called the posterior cingulate cortex. Alzheimer’s patients typically have dramatically reduced blood flow to this area of the brain as well.

The scientists were quick to stress that older people should not rush to get MRIs of their brains. Rather, the technique could be useful in diagnosing those in the very early stages of Alzheimer’s — before any memory loss — so they can try medications aimed at curing, reversing or halting the progression of the disease. After the continued failure of Alzheimer’s treatments, many researchers are now convinced that the best chance of combating this disease is to start treatment before people have symptoms.

A number of biomarker tests have been developed in recent years to diagnose early Alzheimer’s, including positron-emission tomography (PET) tests, which are currently considered the gold standard for brain imaging. But PET tests expose patients to radiation and are not widely available, whereas MRIs do not emit radiation and are readily available and relatively inexpensive.

>> Get discounts on health services with your AARP Member Advantages.

This type of MRI is “simple to perform, doesn’t require special equipment and adds only a few minutes to the exam,” said study author Sven Haller, M.D., of the University of Geneva in Switzerland.

“These findings are important in regard to early detection, because they focus on persons with normal cognition but segregate that [group] into those who stay stable and those who decline within the normal range over 18 months, ” Debra Fleischman, professor of neurological sciences at Rush University Medical Center in Chicago, told WebMD. She added that this MRI technique has promise for finding those at risk for Alzheimer’s and dementia before symptoms have begun, but said more research is needed before it can be used in that way.

Photo: Radiological Society of North America