Eye Cells Used to Detect and Track Alzheimer's Disease

Detecting and tracking Alzheimer's disease may one day be as easy as an eye exam, according to a new study that found a direct tie between the condition and the loss of a particular layer of retinal cells.

The study, presented at this year's Society for Neuroscience conference, included observations of the eyes of mice genetically engineered to develop Alzheimer's.

"The retina is an extension of the brain so it makes sense to see if the same pathologic processes found in an Alzheimer's brain are also found in the eye," Dr. R. Scott Turner, director of the Memory Disorders Program at Georgetown University Medical Center, said in a statement.

Previous studies have focused on the retinal ganglion cell layer responsible for transmitting visual information to the brain using the optic nerve. However, before this process can even begin, a layer in the retina known as the inner nuclear layer has to first hand this data over to the retinal ganglion cells.

In this case, the researchers decided to examine the thickness of the retina, including the inner nuclear layer and the retinal ganglion cell layer, detecting a 37 and 49 percent loss of neurons respectively when compared to the controls.

"This study suggests another path forward in understanding the disease process and could lead to new ways to diagnose or predict Alzheimer's that could be as simple as looking into the eyes," Turner said.

Neither is Alzheimer's the only condition the study could help improve treatment for, the researchers note.

"Parallel disease mechanisms suggest that new treatments developed for Alzheimer's may also be useful for glaucoma," Turner said, noting "We know there's an association between glaucoma and Alzheimer's in that both are characterized by loss of neurons, but the mechanisms are not clear."

Alzheimer's is the most common form of dementia, accounting for 50 to 80 percent of cases, according to the Alzheimer's Association. Though no cure is currently available, current treatments are able to slow the condition's progression.