O.D.s may someday play a role in diagnosing Alzheimer’s disease, thanks to current research on the identification of disease’s ocular markers in the retina, says Peter Snyder, Ph.D., who’s pursuing such research at the University of Rhode Island, in addition to his editorial duties at Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association and Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring. As November is Alzheimer’s Awareness month, Dr. Snyder discusses this research.
“Around 2011, researchers discovered that β-amyloid (Aβ) plaques and neurofibrillary tangles of phosphorylated tau, hallmarks of the presence of Alzheimer’s, could be seen in the retinas of post-mortem patients,” he ex- plains. “As a result of that, additional research is being carried out on identifying biomarkers of early disease onset and progression in the retina.”
Dr. Snyder says the goal is to identify these markers, along with reflective measurements of the disease process, within the next five to seven years and, then, develop tools, such as a specialized high-resolution retinal imaging device, to aid the eye doctor in identifying them. (See bit.ly/2VrEI0B .)
The vision changes definitively associated with Alzheimer’s pa-tients are deficits in backward patterned visual masking tasks, suggesting a major reduction in central visual processing speed; VF loss; saccadic and smooth pursuit eye movement deficits; object recognition difficulty; eye-head coordination impairment; trouble distinguishing objects from others; and impaired reading ability in the presence of normal VA, reports a Journal of Optometry study. The presence of defective VA and color vision, abnormal pupil dilation in response to tropicamide, contrast sensitivity difficulty, reduced pat-tern-ERG response amplitude; and decreases in nerve fiber layer thickness have garnered conflicting results. OM
FOR ADDITIONAL ALZHEIMER’S INFORMATION, DR. SNYDER RECOMMENDS: