Eye Tests May Predict Early Alzheimer’s Disease

2016

Researchers were able to detect evidence of Alzheimer’s development in mice even before detection of plaque build-up was possible.  By using a light flashed into the eyes of mice and evaluating the patterns of reflected light they could see clear evidence of changes in the brain – changes that would naturally develop as beta amyloid plaque later developed in the brain.  The technique has not been expanded for humans yet (as of June, 2016) but is now beginning phase I trials.¹

2014

Early trials of two types of eye tests show promising results in identifying Alzheimer’s Disease in its early stages. Research showed that a key protein can be detected in the retina and lens of the eye through simple tests. Both types of eye tests accurately distinguished healthy patients from those with early stages of Alzheimer’s, which was confirmed by PET (positron-emission tomography) scans.

In one trial, Australian researchers asked 200 participants to take a supplement of curcumin, an ingredient of turmeric spice.

This naturally bright-colored supplement binds strongly to beta-amyloid protein, which clumps in the brain of Alzheimer’s patients. Researchers found that this protein, made fluorescent by curcumin, could also be detected in the retina using simple imaging. From the results of 40 patients, PET imaging confirmed that the test correctly identified all of the participants with Alzheimer’s and 80% of those without the disease.

In the other trial, an ointment was used to detect the same beta-amyloid protein, this time in the lens of the eye. The eye test, conducted by the U.S. company Cognoptix, correctly identified 85% of Alzheimer’s patients in groups of 40 patients. Laser scanning confirmed the same levels of the key Alzheimer’s protein found in the eye.

Though these are early trials using small sample sizes, both tests show promise for early detection and monitoring of Alzheimer’s. Early signs of the disease are difficult to detect, and damage to the brain is often significant before symptoms are noticed. If further research is conducted, these simple, inexpensive eye tests could become part of a regular eye checkup and an essential early step in Alzheimer’s diagnosis.