Simple eye scan can detect early signs of diabetes-related nerve damage

Could a simple eye scan detect early signs of diabetes-related nerve damage? Recent research toward developing such a test is the topic of a special article in Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

The article by Nathan Efron, Ph.D., D.Sc., FAAO, 2010 recipient of the prestigious Glenn A. Fry Lecture Award, presents a review of recent research on ophthalmic markers of diabetic peripheral neuropathy (DPN)—with the goal of developing a quick, painless test to screen for diabetes-related nerve damage at routine eye care appointments. "Looking to the future, this research may pave the way for an expanded role for the ophthalmic professions in diabetes management," Dr. Efron writes.

High-Tech Advances May Lead to Simple Screening Test for Diabetic Nerve Damage
A diabetic himself, Dr. Efron's interest in ophthalmic markers of DPN began more than a decade ago, when Dr. Efron was discussing his own symptoms with his diabetes specialist. Diabetic neuropathy is one of the major long-term complications of diabetes. Affecting about half of diabetic patients, DPN causes symptoms such as numbness, tingling, or pain in the arms and legs. "Patients with numbness may be unaware of foot trauma, which could develop into a foot ulcer," Dr. Efron writes. "If left untreated, this may ultimately require amputation."

In recent years, Dr. Efron has conducted extensive research into ways of detecting DPN by examining the eyes. The connection was made possible through "high-tech" techniques such as corneal confocal microscopy, which permits assessment of corneal nerve structure and function on the cellular level. Using this and other advanced techniques, Dr. Efron and his fellow researchers have discovered that diabetic neuropathy is linked to degradation of the corneal nerves, reduced corneal sensitivity, thinning of the retinal nerve fibers, and peripheral visual field loss.

The researchers hope to combine these four factors into a simple eye scan that can detect diabetic nerve damage in its early stages—even before the patient notices any symptoms. That's important, because currently DPN can only be detected using painful nerve biopsies, or though indirect assessments like sensory testing.

The goal, according to Dr. Efron, is to develop a "rapid, painless, non-invasive, sensitive, reiterative, cost-effective, and clinically accessible means of screening for early detection, diagnosis, staging severity, and monitoring progression of DPN, as well as assessing the effectiveness of possible therapeutic interventions."