January is Glaucoma Awareness Month
Comprehensive eye exams are key to controlling glaucoma
Karen Miller | 1/27/2014, 6 a.m.
Petra Ebisemiju, a 69-year-old retired school nurse, didn’t know much about glaucoma before she was diagnosed with the disease. But she knows a lot now and is absolutely right when she says it is a “tricky little disease.”
For Ebisemiju, the disease started in her left eye about 12 years ago. She went for her yearly eye exam and the doctor told her that her pressure was elevated. “I didn’t know what pressure he was talking about,” she said.
She soon learned. Ebisemiju was diagnosed with angle closure glaucoma, a less common form of the condition. According to the Glaucoma Foundation, angle closure glaucoma is one more typically seen among Asian Americans.
But Ebisemiju had another characteristic often associated with that form of glaucoma. She is farsighted.
By the time she saw the ophthalmologist she said the doctor told her she had lost 95 percent of the vision in her left eye. That news really threw Ebisemiju. Even her driver’s license indicates normal vision. “I can see straight ahead, but I can’t see,” she said. “That’s very shocking.” But she couldn’t see to the side.
Talk about being quirky. Though glaucoma is typically characterized by high pressure in the eye, about one third of those afflicted have normal pressure, according to the Baltimore Eye Study.
That’s why checking pressure in an eye exam tells only half the story, according to Dr. Douglas J. Rhee, the chair of Ophthalmology and Visual Sciences at Case Western Reserve University School of Medicine. Rhee previously a glaucoma specialist at Massachusetts Eye and Ear Infirmary, explained. “The first step should be the appearance of the optic nerve,” he said.
In glaucoma the optic nerve shows an indentation or cupping that results when the pressure is too high for the nerve to tolerate. Nerve damage is identified through dilation of the pupil. A test called tonometry measures the pressure in the eye. Side vision is examined to check for blind spots that people may not even notice.
People should be aware of the risk factors of glaucoma said Rhee. “The biggest one is age,” he explained. Also, 40 percent of those afflicted have relatives with the same disease. Nearsightedness and high blood pressure are factors. So is race. “People of African descent and Hispanics are high risk,” Rhee said. Though glaucoma is the second cause of preventable blindness in this country, it is the primary cause of blindness in blacks. And in the world, for that matter. The reasons for this disparity are unknown.
But there is hope. “We have good treatment,” Rhee said. And the treatments — medicine, laser surgery and incisional surgery — all work well. The type and timing of each depends on the individual’s condition. Most of the time the first line of attack is medicine, but for some, surgery is the first step.
It is important to distinguish between visual acuity and glaucoma, as Ebisemiju quickly learned. Being nearsighted or farsighted is not the same as glaucoma. A person can have 20/20 vision. They can see clearly an object that is 20 feet away, but still have reduced peripheral and tunnel vision and optic nerve damage.