What is glaucoma?
Glaucoma is a condition characterized by increased pressure in
the eye and impaired eyesight, ranging from slight vision loss to total
blindness. Glaucoma is not a single disease, but a group of eye diseases that
have one feature in common: progressive damage to the optic nerve caused by
increased pressure within the eyeball. The pressure comes from a clear fluid
called the aqueous humor. This fluid helps to nourish the eye, and flows in and
out of the eye through a mesh-like channel.
In people with glaucoma, the fluid does not drain properly and
pressure builds up in the eye, damaging the nerve that transmits images to the
brain. As this deterioration of the optic nerve continues, vision worsens, and
eventually, blindness can result.
Glaucoma treatment cannot restore lost vision. But treatment can
prevent additional vision loss from occurring. That is why screening and early
detection of glaucoma are so important.
Are there different types of glaucoma?
There are two main types of glaucoma found in adults:
- Open-angle glaucoma is the most common type, found in approximately
90 percent of glaucoma patients in the United States. In open-angle
glaucoma, the structures in the eye appear to be normal, but fluid does not
drain properly because of tissue changes in and along the drainage passage.
This type of glaucoma has no early warning signs and can go undetected for
years.
- Chronic or acute angle-closure glaucoma accounts for about 10
percent of glaucoma cases in this country. Here, the normal drainage passage
in the eye is narrowed and then becomes blocked.
If either type of glaucoma is diagnosed early enough, a simple
laser treatment can be used to improve the drainage.
Who is most likely to develop glaucoma?
Glaucoma is more commonly found in people over the age of 35. You are more likely to get glaucoma if you:
- Are of African-American descent
- Have family members with glaucoma
- Have diabetes
- Have had a serious eye injury in the past
- Take corticosteroid (Prednisone) medications
Glaucoma is usually present in both eyes, although one eye may
be more affected than the other.
What are the symptoms of glaucoma?
Most patients with glaucoma do not notice any symptoms until
they have lost some of their peripheral (side) vision. Patients often don’t
recognize this until the disease has progressed.
When other symptoms are present, they may include:
- Pain in the eye (If you experience sudden, severe eye pain, headache,
and blurred vision, your internal eye pressure may be very high. You should
call your ophthalmologist or go to an emergency room right away.)
- Redness in the eye
- Vision in one or both eyes appearing hazy
- Seeing halos around lights
- Narrowing of vision (tunnel vision)