(BlackDoctor.org) – Glaucoma occurs about five times more often in African-Americans, and blindness from glaucoma is about six times more common. In addition to this higher frequency, glaucoma often occurs earlier in life in African-Americans—on average, about 10 years earlier than in other ethnic populations.
The disease is often a silent killer — it has no obvious symptoms early on. In fact, as many as half of all people with glaucoma do not know they have the condition. Regular eye exams are important for diagnosing and treating glaucoma — and early treatment is key to saving eyesight.
Glaucoma is actually a group of diseases that can harm the optic nerve, the part of the eye that transmits images to the brain. In most cases, glaucoma occurs when there is an increase in the normal fluid pressure inside the eye. That pressure can damage the optic nerve, causing vision loss and blindness.
Doctors don’t know what causes glaucoma, but they have noted certain risk factors:
• Being 65 years of age or older
• Having a family history of glaucoma
• Being of African, Asian, or Spanish descent
• Being nearsighted or farsighted
• Having had a past eye injury
The Types of Glaucoma
Open-angle glaucoma is the most prevalent type of this eye disease, but it’s not the only one:
• Open-angle glaucoma. In healthy eyes, eye fluids flow into, out of, and around the eye at the open angle where the cornea and iris meet; this angle acts like a drain. Open-angle glaucoma occurs when the fluid doesn’t flow out easily from this drain, causing a build-up of fluid pressure in the eye. That pressure can damage the optic nerve, leading to decreased peripheral (side) vision and vision loss. In the early stages of the disease, people with this type of glaucoma have no symptoms — no pain or changes in vision. They may not know they have it until the disease progresses and their peripheral vision becomes affected. Over time, they lose more of their side vision and can eventually become blind.
• Normal-tension glaucoma. Sometimes damage to the optic nerve can occur in people with normal eye pressure. Doctors are not sure why this happens, but risk factors for normal-tension glaucoma, also called low-tension glaucoma, include a family history of any type of glaucoma or a history of cardiovascular disease.
• Angle-closure glaucoma. This rare type of glaucoma happens when the iris blocks the drain part of the eye. Because eye fluid cannot drain out, pressure can build very quickly, leading to vision loss. Symptoms of angle-closure glaucoma include headache, eye pain, nausea, redness of the eye, and blurred vision. Anyone with these symptoms should seek immediate medical attention. Without treatment, you can lose your sight in just one or two days.
• Congenital glaucoma. This rare, sometimes inherited, type of glaucoma is present at birth. A defect in the drainage system of the eye builds fluid pressure inside the eye, damaging the optic nerve. Symptoms of congenital glaucoma are a cloudy-looking cornea, sensitivity to light, and excessive tearing.
What Is Secondary Glaucoma?
Secondary glaucoma can develop because of an eye injury, eye surgery, inflammation, certain eye tumors, or advanced cataracts. This type of glaucoma can also be a side effect of some drugs, such as corticosteroids. Types of secondary glaucoma include: