One of the greatest challenges in Alzheimer’s Disease research is developing a safe, sensitive and simple-to-use diagnostic tool to detect disease early. Early diagnosis is critical to giving patients earlier access to treatments which might improve their prognosis and potentially slow disease progression. However, the diagnostic tools used today are not cut out to do the job.
“Early diagnosis of Alzheimer’s Disease is a huge unmet need,” said Dr. Sharon Fekrat, Professor of Ophthalmology at Duke University. “It’s not possible for current techniques like a brain scan or lumbar puncture (spinal tap) to screen the number of patients with this disease.”
Dr. Fekrat has published several papers linking eye and brain health. Recently, she and her team published a new article in Ophthalmology Retina, part of the American Academy of Ophthalmology, demonstrating the effectiveness of a noninvasive imaging device that could detect early signs of Alzheimer’s Disease.
The eye is often called the window to the brain, owing to the fact that an optician can see the retina and optic nerve, where visual information is transmitted to the brain. Given the similarities between the brain and the retina, it is thought that the health of the retinal microvasculature might reflect the health of the neural vasculature.
The researchers were able to visualize the blood vessels using a technique called optical coherence tomography angiography (OCTA). Altogether, they examined the eyes of over 200 study participants, some with Alzheimer’s Disease, some with mild cognitive impairment and the rest with no impairment (controls). OCTA allowed the team to measure retinal blood vessel density as well as the thickness of different ocular layers.
The researchers found that people with Alzheimer’s Disease had significantly reduced vessel density, perfusion density and reduced thickness of one portion of their retinas compared to people with mild cognitive impairment and healthy controls. These findings suggest that there could be a correlation between retinal blood vessel health and cognitive health.
“If we can detect these blood vessel changes in the retina before any changes in cognition, that would be a game changer,” Dr. Fekrat added.
While originally designed for optic pathologies, OCTA has become increasingly popular in the study of neurological disease. This noninvasive, high-resolution technology has allowed researchers to study retinal abnormalities in animal models of stroke, traumatic brain injury and Parkinson’s Disease. According to clinicaltrials.gov, there are four active clinical trials involving OCTA and Alzheimer’s Disease.
With a growing elderly population, the incidence of Alzheimer’s Disease is expected to increase. While a cure has yet to be found, catching the disease early can still improve a person’s quality of life.
At the close of Brain Awareness Week, take some time to celebrate the successes in brain research. Read more about new frontiers in Alzheimer’s Disease research here.