Two new studies presented at the American Academy of Ophthalmology’s annual meeting in Chicago suggest that a noninvasive eye scan may be able to detect Alzheimer’s disease early on.
For the first study, researchers at Duke University used an imaging technique called optical coherence tomography angiography to compare the retinas of patients diagnosed with Alzheimer’s, patients with mild cognitive impairment and healthy people.
OCTA has been previously used to study the effects of dementia on the retina, enabling ophthalmologists to study the veins and red blood cells at the back of the eye.
They found that individuals with Alzheimer’s had “loss of small retinal vessels at the back of the eye and that a specific layer of the retina was thinner,” whereas scans of those with even mild cognitive impairment didn’t show such changes, study authors wrote in a news release. Such changes in the retina may indicate evidence of disruptions in the brain’s blood vessels commonly found in Alzheimer’s patients.
“This project meets a huge unmet need,” study co-lead Sharon Fekrat said. “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. Almost everyone has a family member or extended family affected by Alzheimer's. We need to detect the disease earlier and introduce treatments earlier.”
In the second study from the Sheba Medical Center in Israel, researchers examined 400 individuals genetically prone to develop Alzheimer’s
After comparing their brain scans and retina images with patients without a high genetic risk of the disease, they found that the retina is thinner and the hippocampus smaller in those with a family history. Like in the first study, such changes may indicate signs of dementia.
Ygal Rotenstreich, author of the second study, echoed Fekrat’s statements.
“A brain scan can detect Alzheimer's when the disease is well beyond a treatable phase,” he said. “We need treatment intervention sooner. These patients are at such high risk.”
Alzheimer’s disease is the sixth leading cause of death in the United States. In fact, the death rate from the disease has risen by 55 percent in recent decades, according to the CDC. And in Georgia, the number of deaths from Alzheimer's has increased by 201 percent since 2000, according to Georgia Health News.
The Atlanta-based Centers for Disease Control and Prevention recently revealed that the country’s burden of Alzheimer’s disease and related dementias will double by the year 2060.
In 2014, 5 million Americans — or 1.6 percent of the population — felt the burden of the diseases. The figure is expected to grow to 13.9 million, equating to nearly 3.3 percent of the projected population in 2060.