A glimpse in an eye might soon be enough to diagnose the nerve damage associated with diabetes, New Scientist reports.
Up to 50% of diabetes patients experience nerve damage – which could lead, in extreme cases, to the loss of limb sensation, requiring amputation.
Diabetes affects peripheral nerves, or those found outside of the brain and spinal cord. In diabetics, those nerves lose their function because excess glucose in the blood reduces blood flow to arms and legs.
“You are starving the nerve fibers of nutritious oxygen,” says study researcher Nathan Efron from the Queensland University of Technology.
Invasive tests, such as nerve and tissue biopsies, are typically employed to assess nerve fiber damage.
So in search of a noninvasive alternative, Efron and colleagues looked to the cornea, the clear front window of the eye. Since the cornea is the most densely innervated tissue in the body, he reasoned that diabetes might also leave a signature in there.
Using something called a corneal confocal microscope, they found that, on average, the corneas of diabetics with nerve damage have a lower density of nerve fibers and the nerves are shorter than in healthy controls.
The team has developed a clinical test based on the findings. Team member Rayaz Malik at the University of Manchester developed software that compares images of the central cornea with those taken from diabetics with varying degrees of nerve damage. The test is now being used by several hospitals.
They presented the work at the Asia Pacific Academy of Ophthalmology Congress in Sydney last week. Via New Scientist.
Image: Bea Loves photography via Flickr
