IU professor creates instrument to diagnose early diabetes symptoms

An IU professor has designed and built technology that could help doctors diagnose early signs of vision loss due to diabetes.

Stephen Burns, associate dean for graduate programs at the IU School of Optometry, created an instrument that reflects light into patients’ eyes to overcome damage and imperfections in the eye, according to an IU news release.

According to the release, existing techniques that included magnifying images of blood vessels did not give researchers enough information to diagnose early signs of vision loss. Burns’ technology compensated for imperfections in patients’ eyes and allowed more accurate images.

Diabetes damages the retina by causing change and damage to blood vessels in the eye. According to the release, this damage is called diabetic retinopathy. It is the leading cause of vision loss in the United States for people younger than 75 years old.

An IU study that used Burns’ technology found changes in the capillaries of patients with diabetes. Blood vessel walls grew in length and distorted to create corkscrew-shaped loops.

The instrument designed by Burns minimized optical errors and captured large, sharp images of capillaries in the eye. Researchers were able to look at highly magnified still images and videos to observe blood cells moving through the blood vessels.

Ann Elsner, associate dean for research at the optometry school and lead author of the study, said the researchers were not expecting to see such significant changes to patients’ eyes at the early stages.

“We set out to study the early signs, in volunteer research subjects whose eyes were not thought to have very advanced disease,” Elsner said in the release. “There was damage spread widely across the retina, including changes to blood vessels that were not thought to occur until the more advanced disease states.”

Subjects with diabetes had blood vessels that were broader, with significantly thicker walls, according to the release. Thick blood vessel walls have been correlated with poor blood flow and poor flow regulation.

In addition to changes in the blood vessel walls, some of these capillaries were closed and could no longer move blood in the retina.

This meant that diabetic patients who were thought to have only mild symptoms were already on a path to suffer vision loss.

“It is shocking to see that there can be large areas of retina with insufficient blood circulation,” Burns said. “The consequence for individual patients is that some have far more advanced damage to their retinas than others with the same duration of diabetes.”

Tori Fater