The Grapevine

Alzheimer's Diagnosis: Eye Doctors May Soon Detect Disease Even Without Symptoms

Predicting the development of Alzheimer's disease may soon be as easy as going to the clinic to get your eyes checked. A new study showed that the neurodegenerative disease can actually be detected through a simple and quick eye exam. 

The research at the Duke Eye Center in North Carolina found that the loss of blood vessels in the retina could signal Alzheimer's disease. People with healthy brains commonly have a dense web at the back of the eye inside the retina that’s formed by microscopic blood vessels.

However, the web loses its density when Alzheimer's disease develops. The findings, published in the journal Ophthalmology Retina, come from the analysis of the eye health of more than 200 people.

To detect changes in the eyes, the team used a new noninvasive technology that takes high-resolution images of tiny blood vessels within the retina. Researchers said the process only takes “just a few minutes,” EurekAlert reported Monday

"We're measuring blood vessels that can't be seen during a regular eye exam,” Sharon Fekrat, the study's senior author and a Duke ophthalmologist and retinal surgeon, said in the report. "It's possible that these changes in blood vessel density in the retina could mirror what's going on in the tiny blood vessels in the brain, perhaps before we are able to detect any changes in cognition."

The tool used in the study, called optical coherence tomography angiography (OCTA), uses light waves that reveal blood flow in every layer of the retina. OCTA also scans the eyes for changes in tiny capillaries. 

"Ultimately, the goal would be to use this technology to detect Alzheimer's early, before symptoms of memory loss are evident, and be able to monitor these changes over time in participants of clinical trials studying new Alzheimer's treatments," Fekrat said.

The Duke Eye Center researchers also used OCTA to analyze other changes in the retina that could signal changes in the brain when people begin to suffer Alzheimer's, such as thinning of some of the retinal nerve layers.

To date, estimates show that nearly six million people in the U.S. are living with Alzheimer's disease. However, noninvasive tools for early diagnosis of Alzheimer's disease are currently not available in clinics.