The beta-amyloid plaques that kill the neural tissue of people with Alzheimer’s disease accumulate in retinal tissue before other parts of the brain. These plaques usually develop in the brain before there are symptoms of cognitive decline. Since there is no way to detect plaques in the brain, detection in the retinas would be the first sign of the onset of Alzheimer’s. New retinal imaging techniques may allow scientists to diagnose Alzheimer’s earlier than it would be otherwise.
In a new study, plaques were found in the retinas of patients who were thought to be in the early stages of Alzheimer’s. The researchers in the study also genetically modified rats to develop Alzheimer’s. They injected a fluorescent coloring in the brains of the rats so they could identify plaques. The researchers were able to see plaques in the retinas before they could see any plaques form in the brain. Also as the rats received therapy for Alzheimer’s the amount of plaque in the retina diminished.
This exciting research could potentially lead to a method of detecting the onset of Alzheimer’s earlier in human patients. Also it would be an effective way to evaluate various treatments of the disease. Dr. Francesca Cordeiro, who led the study, added, “Currently, the biggest obstacle to research into new treatments for neurodegenerative diseases is the lack of a technique where the brain’s response to new treatments can be directly assessed – this technique could potentially help overcome that.”