Researchers may be on track to creating an eye test that pinpoint Alzheimer's and track its progression.

The team observed a previously-unstudied layer of retinal cells that degenerated in mice that had been genetically altered to get Alzheimer's, a Georgetown University news release reported.

"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," explains R. Scott Turner, MD, PhD, director of the Memory Disorders Program at GUMC and the only U.S. author on the study, said. "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." 

Past research of the eyes in association with Alzheimer's disease has focused primarily on the "retinal ganglion cell layer," which is responsible for transmitting visual information to the brain. Before the cell layer transmits the images through the optic nerve the ganglion cells receive information from the inner nuclear layer.

The researchers observed the thickness of the retina, including the inner nuclear layer which had never been studied before in realation to Alzheimer's.

The team found the inner nuclear layer lost 37 percent of its neurons while the inner nuclear layer lost 49 percent.

Medical experts would be able to measure this retina thinning, which would be an indicator of the disease, using optical coherence tomography. 

"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 says. "Parallel disease mechanisms suggest that new treatments developed for Alzheimer's may also be useful for glaucoma."

Researchers also recently came up with a new method that could predict how long it would take for an Alzheimer's patients to need assistance with everyday life, and how much time they had left before passing away. These predictions could help families plan the future care of their loved ones, a Columbia University Medical Center news release reported.