Glaucoma can strike at any age
Karen Miller | 1/28/2014, 6 a.m.
Chance Flaherty knew something was wrong with his vision several years ago. He could not read the Jumbotron at a Celtics game. Nor could he see the numbers on the back of the players’ jerseys. But he never suspected glaucoma. After all, he was only 14.
An examination by an optometrist confirmed his nearsightedness, but it also confirmed elevated pressure, or glaucoma, in both his eyes. The optometrist knew that glaucoma tends to run in families. Flaherty’s mother, Shelley, wasted little time in having her entire family tested.
Everyone tested normal. But not Demetri, Chance’s twin brother. Not only was he nearsighted, the pressure in both of his eyes also exceeded the normal limit, the right eye worse than the left. Instead of the average eye pressure of 11 to 21 mm Hg (millimeters of mercury) his pressure exceeded 30. It was later determined that both Demetri and Chance had primary open angle glaucoma — the most common form of the disease.
Without much warning or fanfare more than two million people in the United States slowly begin to lose their sight. And they don’t even know it. According to experts, by the time they notice a change, more than 50 percent of their vision has been permanently lost.
Most often the first symptom is the loss of peripheral or side vision. That’s why it escapes notice. You don’t need peripheral vision to watch TV, work on the computer or read. But there’s another reason for the lack of awareness, according to Dr. Douglas J. Rhee, the chair of Ophthalmology and Visual Sciences at Case Western Reserve University School of Medicine. Rhee, formerly an ophthalmologist at Massachusetts Eye and Ear Infirmary, explained “the brain does funny things.” But it’s not trying to play tricks; it is actually being protective. Glaucoma causes blind spots in our vision, so the brain fills them in for us, Rhee said.
Yet, without treatment, glaucoma — the second leading cause of blindness in this country — slowly advances. Eventually, the scope of vision is so limited, it’s as though one is looking through a tunnel or telescope. Ultimately, the disease can result in permanent and total vision loss.
No one — not even babies and children — is safe from glaucoma. African Americans and Hispanics are afflicted more. And earlier. Glaucoma often strikes blacks around the age of 40. Asians are also afflicted, but tend to suffer from a less common form of glaucoma.
By 60, everyone is fair game.
Glaucoma results from increased eye pressure. The eye is filled with and nourished by a clear fluid that continually flows, but must drain to accommodate a fresh incoming supply. In most types of glaucoma the fluid does not drain properly causing eye pressure to rise.
Elevated pressure can eventually destroy the optic nerve, a bundle of more than one million nerve fibers that connects the retina (tissue at the back of the eye) with the brain. A healthy optic nerve is necessary for good vision.