Twelve individuals in the study were known to have diabetic retinopathy, a disease in which blood vessels in the eye are damaged. The individuals with diabetic retinopathy in at least one eye had significantly greater FA activity than people with diabetes who do not have any visible eye disease.
"The abnormal readings indicated that it may be possible to use this method to monitor the severity of the disease," says Elner.
Petty, a biophysicist and imaging expert, explains that hyperglycemia - or high blood sugar - is known to induce cell death in diabetic tissue soon after the onset of disease but before symptoms can be detected clinically.
"Increased FA activity is the earliest indicator that cell death has occurred and tissue is beginning to break down," says Petty, professor of Ophthalmology and Visual Sciences, and professor of Microbiology and Immunology at the U-M Medical School. "FA serves as a 'spectral-biomarker' for metabolism gone awry, and we can use the results to detect and monitor disease."
Petty also observes that unlike glucose monitoring, elevation of FA levels reflects ongoing tissue damage. That knowledge, he says, could motivate patients to intensify their efforts to manage the disease.
The Michigan researchers also note that elevated FA does not always mean that an individual has diabetes. "Because of the prevalence of diabetes in our population, individuals with abnormally high FA would be prompted to undergo glucose tolerance testing," says Elner. "If the findings were negative for diabetes, we would look for other causes of ocular tissue dysfunction."
Both Elner and Petty agree that the device has great potential as a tool for diabetes screening and management. "So much damage occurs before the disease can be detected by a doctor," says Elner. "Early diagnosis will allow us to reduce organ damage and prevent many complications that accompany this disease."
Elner and Petty have filed for patents and have formed a company, OcuSciences, Inc., to commercialize the metabolic imaging instrument.
Back to HCB News