Durham, N.C. — A break-through technology at Duke University Medical Center can help diagnose a leading cause of blindness that routine eye exams can miss.
Narrow-angle glaucoma is much less common than the open-angle version of the disease but is three times more severe. The disease prevents fluid from draining out of the eye.
A Duke ophthalmologist, however, has developed an infrared camera that lets doctors see the interior structures of the eye in greater detail than other machines do.
Getting a routine eye exam led to a trip to Duke and a sight-saving diagnosis for glaucoma patient Wayne Thorpe.
"There's nothing like being able to see," Thorpe said. "When you've seen for 59 years, you want to continue seeing."
During an eye check-up two years ago, Thorpe began feeling severe pain in his eye. Within two hours, he was at Duke Eye Center, and Asrani had used the one-of-a-kind infrared camera to find the problem.
The natural drainage of Thorpe's eye was closed.
"And if it does get closed, then the pressure can go up, and the person can get an attack of glaucoma," said Dr. Sanjay Asrani, an ophthalmologist with Duke.
The standard test for narrow-angle glaucoma can distort the natural shape of eye structures, making a diagnosis difficult, Asrani said.
The new infrared camera, though, never touches the patient but offers a detailed cross-sectional view of the eye – and the effects on eye structures caused by glaucoma.
"It's amazing that until this machine, we have never seen it live in an individual," Asrani said.
In a healthy eyeball, a natural filtration system moves fluid from the pupil, over the iris and into the corners of the eye. A thin channel then drains the liquid away from the eyeball.
The infrared camera helped Thorpe get a quick diagnosis and treatment.
"We were lucky to be able to treat him with eye drops and then subsequently with a laser," Asrani said.
The five- to 10-minute procedure relieved the pressure of Thorpe's eye.
"I think I caught it just in time, because I haven't have a bit of problems since then," he said.
Only Duke has used the infrared camera for investigative purposes, but Asrani said he has started to search for a company to mass produce it.
The camera would likely first be available to academic medical centers, but Asrani said he can imagine it becoming standard equipment in every eye doctors' office within the next decade.
The detailed images of eye structures will let doctors better study the more common open-angle glaucoma and help give patients a better understanding of their condition and treatment.