New findings from scientists who examined the fundus of patients' eyes suggest a possible connection to Alzheimer's. The current study shows how imaging measures blood flow in the back of the eye. In addition, this allows for a non-invasive method thatdetect early onset Alzheimer's disease.
Use imaging to examine the fundus of the eye
The researchers wanted to investigate the idea that changes in the capillaries of theRetina in the back of the eyeCan reveal changes in the brain. These are otherwise undetectable and usually occur before the diagnosis of Alzheimer's or dementia, according to the study authors. The research involved 13 people with a rare, genetically inherited form of early-onset Alzheimer's disease. This is characterized by mutations that were identifiable in three genes. This form of familial Alzheimer's disease affects approximately 1% of all patients with this disease. Using an imaging technology called optical coherence tomography angiography, researchers were able to examine the back of the eye through images of blood vessels. The study participants were with and without a mutation that could lead to the familial form of Alzheimer's disease. The team also cataloged the stage of disease for people with Alzheimer's and the cognitive abilities of both groups.
The scientists found that abnormal blood flow through the smallest vessels in the back of the eye correlates with the mutations in the people studied who are at risk for the familial form of Alzheimer's disease. Patients with such abnormalities who showed no signs of disease had unusually high and heterogeneous blood flow in the capillaries of their retinas. Researchers believe this may be an early sign of inflammatory changes involved in the pathogenesis of Alzheimer's disease. Furthermore, the authors claimthis studythat these data support the assumption that changes in the eyeshow the earliest signs of brain diseasecan before symptoms are present. With further evidence from larger studies over time, they also believe the method could provide clinicians with a tool for earlier diagnosis and enable an intervention to slow cognitive decline in patients.
