In the search for better diagnosis of traumatic brain injury, researchers have looked everywhere. They have looked at brains with every type of scan they have, investigated biomarkers in the blood, and they’ve even considered checking the mouth for indicators of a brain injury. It turns out, the indicator they may be looking for may be the eyes.
Doctor Randy Kardon, director of Neuro-Ophthalmology spoke at the annual meeting of the Association for Research in Vision and Ophthalmology over the weekend where he explained a new type of eye scan, called optical coherence tomography, or OCT, to explore the retinas of veterans exposed to blasts. There, he found thinner cell layers than normal subjects.
Kardon also developed a test which helped validate the common complaint of blast-exposed brain injury patients of extreme light sensitivity. Kardon connected small electrodes to the muscles around the eye, where he recorded more involuntary blinking and squinting among veterans with TBI. We still don’t know what causes this sensitivity or whether the thinner cell layers in retinas are associated. However, light sensitivity has also long been corroborated with slower pupil dilation compared to control subjects.
The Seattle Times has reports from Kardon’s presentation, as well as many others exploring brain injury. A few of the other scientists showed similar evidence that the eye may be a key part in a quick and efficient brain injury indicator, though most tests were only in preliminary stages and would need to be tested on larger samples.