A world-first trial in Australia aims to develop an eye test to detect early signs of Alzheimer’s disease and researchers believe optometrists will be on the front-line using the technology.
Centre for Eye Research Australia (CERA) researchers received a major funding boost to fast-track their research enabling Melbournians to participate in the trial of eye scans based on imaging technology similar to that used in NASA satellites.
Deposition of a certain protein in the brain over many years is a characteristic of Alzheimer’s disease and recent research indicates that it also accumulates in the retina.
Using specialised colour imaging, cameras developed by the team at CERA aim to measure this protein in the retina years before signs of cognitive decline.
The Alzheimer’s Drug Discovery Foundation (ADDF), a partnership of American philanthropists including Bill Gates, will provide more than $600,000 for the research.
The study will establish whether the new eye imaging technique can replace brain positron emission tomography (PET) imaging and lumbar punctures for Alzheimer's diagnosis and detect early signs before cognitive decline.
Healthy brain check
One of the developers of the technology, ophthalmologist Associate Professor Peter van Wijngaarden said optometrists were at the front line of eye care and this retinal imaging method could provide new insights into brain health.
“There is currently no screening test for Alzheimer’s disease but retinal imaging might fill that gap,” he said.
“It might be a screening test offered as part of a routine eye test by an optometrist, to identify where people are on the risk spectrum and monitor their risk over time. It could have tremendous value.”
Professor van Wijngaarden said that currently by the time people present with symptoms and signs of dementia, the disease has been in progress for up to 20 years and many irreversible changes have already occurred. This scan could allow much earlier intervention, with potential for future drug treatments to prevent the disease, or delay its onset.
Pilot studies have determined the scan can distinguish people with and without early Alzheimer’s disease and the next phase is a large validation study to determine how early the biomarkers can be identified.
The study, to start in August, will enrol 500 people from the Healthy Brain Project who are cognitively normal at baseline but whose relatives have dementia. The retinal imaging test will be compared with brain imaging, cognitive testing and cerebrospinal fluid biomarkers.
Portable cameras
The researchers used an expensive research camera for the retinal scans, but the team is developing a cheaper, portable prototype camera which could eventually be used by optometrists. The trial will also compare the prototype with the research camera.
Professor van Wijngaarden expected it would be a few years before the technology could be available for use but said it was very promising and advised to "watch this space".
People interested in volunteering for the Healthy Brain Project should visit the Healthy Brain Project website or email healthybrainproject@florey.edu.au.
