(PhysOrg.com) -- A ringing alarm clock signaled the loss of sight for Indianapolis entertainer Jimmy Gilford.
"I was lying on my back, and I could not see the clock when the alarm went off. When I sat up, I could see it. When I laid back down, I still couldn't see it," Guilford said.
Guilford was soon diagnosed with glaucoma -- and had already lost vision in his right eye because of the disease. "I never had a pain or anything, and I didn't notice any change in my sight," Guilford said.
Dr. Louis B. Cantor, chairman of the Department of Ophthalmology at the Eugene and Marilyn Glick Eye Institute at the Indiana University School of Medicine, urges adults to learn about the disease and its risk factors during "Glaucoma Month," observed in January by the American Academy of Ophthalmology.
"Glaucoma, one of the leading causes of blindness in the United States, is often called the sneak thief of sight because it can occur without warning signs or symptoms," Cantor said. "Individuals may experience some vision loss before they realize they have a problem -- and often that lost sight cannot be restored."
Risk factors for glaucoma include:
• Being African-American or Hispanic
• Having a family history of glaucoma
• Having elevated eye pressure
• Being farsighted or nearsighted
• Having previous eye injuries
• Having other health problems such as diabetes, low blood pressure or migraine headaches.
Guilford, who is African-American, says his mother's family had a history of glaucoma, but he still didn't realize he was at risk for the disease. "With my job as an entertainer, I didn't do too much reading. If I wanted to get the news, I'd just turn on the TV. But when I tried to read some sheet music, I realized my eyesight was not too good. I just got some of those drug-store glasses, and I thought it would be okay," he said.
As we age, many of us will experience some changes in our vision, Cantor explained. "Most people will require reading glasses around the time they turn 40. And, said Cantor, by age 65, one in three Americans will experience some form of vision-impairing eye disease.
Guilford was diagnosed with glaucoma about 20 years ago, in his fifties. "I had no pain, no strain -- now I've just got a small bit of vision remaining in my left eye," Gilford said.
Cantor said glaucoma develops when pressure builds in the eye and causes damage to the optic nerve. The nerve is the main cable carrying the messages from the eye to the brain. The damage to the optic nerve can cause blind spots to develop, and those spots often go unnoticed until they increase in size and impair more of your sight. Blindness is a result if the disease is left untreated, Cantor said.
Once vision loss from glaucoma is noticeable or measurable, the disease is often in advanced stages. Damage to the nerve can be prevented with medications such as eye drops, laser treatment or surgery, but it cannot be reversed and sight cannot be restored, Cantor said.
The two most common types of the disease are primary open-angle glaucoma and acute closed-angle glaucoma. Treatment will depend on the type and severity of the disease.
Cantor said primary open-angle glaucoma is the most common form of the disease and is caused when the fluid normally produced in the eye is blocked from flowing back out of the eye at a normal rate, causing pressure in the eye to build. Acute closed-angle glaucoma is caused when the iris, or colored part of the eye, can block the drains in the eye, increasing eye pressure.
"In some cases, there is a sudden increase in eye pressure due to the build-up of fluid," Cantor explained. "When this happens, it is considered an emergency, because nerve damage and sight loss can occur within hours. This type of glaucoma often comes with symptoms such as eye pain, seeing halos around lights, and nausea and vomiting." Cantor said the sudden onset of those symptoms should be treated as an emergency.
The best defenses against eye diseases such as glaucoma are awareness of risk factors and regular eye exams, said Cantor, who also directs glaucoma research at Indiana University. Dilated eye exams, which allow the ophthalmologist to see the back of the eye, are particularly important for people with glaucoma or diabetes.
"Early detection is the best defense against glaucoma," Cantor said. "Treatment can stall the progression of glaucoma, but it won't cure it or restore lost vision."
Guilford has not let the disease hamper his lifestyle.
"I did have to give up driving in 2003, and I'd been motorized since I was 15," Guilford said. "But I'll go to work tonight, and I'm going to entertain. There's no sense crying over spilled milk."
Guilford said it's important for young people to have eye exams at a young age to check for the disease. "We need to make sure the young people are being tested and checked, and be able to control it and take care of it. It is a silent disease -- it sneaks in and boom, you're blind."