Eye Tests for Alzheimer’s Enter Trials
Since Alzheimer's disease, which is a form of dementia, is incurable, finding ways to prevent it from manifesting or at least slow down the progress of the disease is vital in extending people's quality of life. Based from previous research, scientists have tied amyloid plaque deposits, which are proteins found in the brain, in the eyes as markers for Alzheimer's disease. Based on this correlation, there were two non-invasive retinal tests devised to detect Alzheimer's disease before symptoms would even show. Now, these two tests are undergoing trials to see if they are indeed effective in detecting this neurodegenerative illness.
"The key for having an effective treatment for AD is early detection. You want to prevent those brain cells from being killed or dying in the first place," said Professor Keith Black, chairman of the Department of Neurosurgery at Cedars-Sinai Medical Center in Los Angeles, and co-founder of NeuroVision.
NeuroVision has created one of the two new devices called the Retinal Amyloid Index. The other device is created by Cognoptix and is called Sapphire II. Both of these tests inform doctors whether or not there are amyloid plaque deposits in the eye. Sapphire II scans the eyes to look for photons, which correlates to amount of amyloid plaque deposits present. Amyloid has long been associated with Alzheimer's disease. Therefore, if these deposits are present in the eye, they could indicate a patient's risk factor for Alzheimer's. Researchers believe that these plaque deposits could detect the illness up to 20 years before it would even start to affect mental health.
"Ocular exams through the years have attempted to diagnose Alzheimer's at an early age," Michael Tolentino, MD, PRIMARY CARE OPTOMETRY NEWS Editorial Board member, said. "We have looked at optic nerve cupping, pupillary response to tropicamide dilation and ocular muscle movement. While all have been investigated, all have failed to withstand the test of time in terms of sensitivity and specificity, and all were subjective in nature. Cognoptix and NeuroVision are trying to objectify the diagnosis."
Both devices are going through phase I of II trails. Phase III is expected to start in 2014.