New techniques using magnetic resonance imaging may help scientists discover Alzheimer's-like brain changes earlier, while other MRI research is helping scientists learn more about how the disease progresses, according to several studies presented Sunday at the International Conference on Alzheimer's Disease in Chicago.
 

Researchers announced that for the first time, images of brain plaques — like those implicated in Alzheimer's-like dementia — were captured using conventional, clinical-strength MRI.

Many tools are used to look for signs of Alzheimer's, including a battery of cognitive and behavioral tests, MRI scans and imaging studies called PET scans that require the injection of special chemicals that help light up the brain. But doctors can make a definitive diagnosis only after a patient dies by identifying the presence of brain lesions called amyloid plaques.

The ability to spot amyloid plaques in the brain of a living person using MRI could improve diagnosis of Alzheimer's, including earlier diagnosis, allowing patients to try drug and other therapies earlier in an effort to help slow the disease's progression.

Alzheimer's disease is estimated to affect as many as 5.2 million Americans — a number expected to swell to as many as 16 million by 2050.

In a study by Robarts Research Institute and the University of Western Ontario, researchers used MRI scanners customized for micro-imaging to identify brain plaque in animals, visualizing amyloid plaque for the first time with a conventional MRI. "This preliminary discovery hints at the promise of using clinical MRI scanners to visualize plaques in people with Alzheimer's," says study co-author John Ronald. Other MRI findings:

Researchers from the University of Pennsylvania and the National Institute on Aging used a new computer-based technique to analyze MRI scans from normal elderly and mildly cognitively impaired adults. "Instead of looking at each brain region in isolation … it actually integrates and detects spatial patterns," says Christos Davatzikos, a professor in Penn's department of radiology.

Mayo Clinic researchers used a new MRI analysis algorithm to capture Alzheimer's-related neurofibrillary tangles — another postmortem hallmark of Alzheimer's disease.

A study by Robyn Honea at the University of Kansas Medical Center showed MRI brain imaging may be used to show a connection between cardiorespiratory fitness and Alzheimer's-related changes in one of the first brain regions to suffer damage. The study found more physically fit people had less brain atrophy.

Neil Buckholtz, a scientist at the National Institute on Aging, says the new techniques hold promise, but "it will take more longitudinal studies before we know what it all means."