A study led by the Cedars-Sinai Department of Neurosurgery has identified certain regions in the retina - the lining found in the back of the eye - that are more affected by Alzheimer's disease than other areas. The findings may help physicians predict changes in the brain as well as cognitive deterioration, even for patients experiencing the earliest signs of mild impairment. "These clues can occur very early on in the progression of Alzheimer's disease - several decades before symptoms appear," said Maya Koronyo-Hamaoui, Ph.D., associate professor of Neurosurgery and Biomedical Sciences and co-corresponding author of the study. The findings of the new study, published in the journal Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring, were from a clinical trial involving people older than 40 who were showing signs of cognitive decline. In the trial, investigators used a non-invasive technique known as sectoral retinal amyloid imaging to capture retinal images in participants. The retina, which is directly connected to the brain, is the only central nervous system tissue accessible for patient-friendly, high-resolution, and non-invasive imaging. The images were then analyzed using a new process that could identify certain peripheral regions in the retina that corresponded better to brain damage and cognitive status. Both studies show promise for diagnosing and treating Alzheimer's disease, a condition affecting more than 5.5 million people in the U.S., said Keith Black, MD, professor, and chair of the Department of Neurosurgery.