Eye Test to Detect Alzheimer’s Disease Before Symptoms Start

At Washington University School of Medicine in St. Louis researchers may have spotted signs of Alzheimer’s disease within patient eyes, potentially leading to a non-invasive and rapid test for the disease. “This technique has great potential to become a screening tool that helps decide who should undergo more expensive and invasive testing for Alzheimer’s disease prior to the appearance of clinical symptoms,” said Bliss E. O’Bryhim, MD, PhD, one of the study authors appearing in journal JAMA Ophthalmology. “Our hope is to use this technique to understand who is accumulating abnormal proteins in the brain that may lead them to develop Alzheimer’s.”

Reporting in JAMA Ophthalmology, the team used optical coherence tomography (OCT) to look at the retinas of 30 older adults without symptoms of Alzheimer’s. These same patients underwent PET scans and lumbar punctures to sample the cerebrospinal fluid. About half of the group ended up having a higher amyloid and tau protein count than normal, pointing to the eventual onset of Alzheimer’s symptoms. These same patients, coincidentally, had thinner retinas, something that was previously discovered during autopsies of former Alzheimer’s sufferers.

While traditional OCT imaging can provide measures of the thickness of the retina and the fibers within the optic nerve, the Washington University team added another device that detects red blood cells moving through the retina. This gave them a view into the blood flow characteristics, which showed that those patients that had raised amounts of Alzheimer’s-related proteins in their bodies also had an enlargement of the center of the retina where there are no blood vessels.

While more studies are needed to verify these results, there’s now great hope that Alzheimer’s can be detected long before symptoms appear without having to go through unpleasant procedures such as lumber punctures.

Study in JAMA Ophthalmology: Association of Preclinical Alzheimer Disease With Optical Coherence Tomographic Angiography Findings…

Image: Greg Van Stavern, MD, runs a test on “patient,” Kathleen Eisterhold, as Raj Apte, MD, looks on at the Center for Outpatient Health. The OCT angiography test seems to correlate with the development of Alzheimer’s disease pathology. Credit: Matt Miller/Washington University School of Medicine

Via: Washington University School of Medicine…