Health Issue: Glaucoma
Symptoms and Types
Glaucoma is the second most common cause of blindness in the United States. There are four major types of glaucoma:
- Angle-closure (acute) glaucoma
- Congenital glaucoma
- Open-angle (chronic) glaucoma
- Secondary glaucoma
All four types of glaucoma are characterized by increased pressure within the eyeball, and therefore all can cause progressive damage to the optic nerve.
The front part of the eye is filled with a clear fluid called the aqueous humor. It is constantly made in the back of the eye then leaves the eye through channels in the front chamber of the eye. In angle-closure (acute) glaucoma, when the exit of the aqueous humor fluid is suddenly blocked, pressure increases and loss of vision and pain develop. Dilating eye drops and certain systemic medications may trigger an acute glaucoma attack if you are at risk.
In open-angle (chronic) glaucoma, the cause is essentially unknown. An increase in eye pressure pushes on the junction of the optic nerve and the retina at the back of the eye, reducing the blood supply to the optic nerve. Open-angle glaucoma tends to run in families. Your risk is higher if you have a parent or grandparent with open-angle glaucoma. People of African descent are at particularly high risk for this disease.
Congenital glaucoma often runs in families (hereditary) and is present at birth.
Secondary glaucoma is caused by the use of drugs such as corticosteroids, several eye diseases, and systemic diseases.
All four types of glaucoma are characterized by increased pressure within the eyeball, and therefore all can cause progressive damage to the optic nerve. Open-angle (chronic) glaucoma is by far the most common type of glaucoma.
The front part of the eye is filled with a clear fluid called the aqueous humor. This fluid is constantly made in the back of the eye. It leaves the eye through channels in the front (anterior) chamber of the eye in an area called the anterior chamber angle, or simply the angle.