What is glaucoma?
Glaucoma is a disease of the optic nerve - the part of the eye that carries the images we see to the brain. The optic nerve is made up of many nerve fibers, like an electric cable containing numerous wires. When damage to the optic nerve fibers occurs, blind spots develop. These blind spots usually go undetected until the optic nerve is significantly damaged. If the entire nerve is damaged, blindess results.
Early detection and treatment by your ophthalmologist are the keys to preventing optic nerve damage and blindess from glaucoma.
Glaucoma is a leading cause of blindness in the United States, especially for older people, but loss of sight from glaucoma can often be prevented with early treatment.
What causes glaucoma?
Clear liquid called aqueous humor circulates inside the front portion of the eye. To maintain a healthy level of pressure within the eye, a small amount of this fluid is produced constantly while an equal amount flows out of the eye through a microscopic drainage system. This liquid is not part of the tears on the outer surface of the eye.
Because the eye is a closed structure, if the drainage area for the aqueous humor- called the drainage angle- is blocked, the excess fluid cannot flow out of the eye. Fluid pressure within the eye increases, pushing against the optic nerve and causing damage.
Who is at risk for glaucoma?
Your ophthalmologist considers many kinds of information to determine your risk for developing the disease.
The most important risk factors include:
- Elevated eye pressure
- Family history of glaucoma
- African or Hispanic ancestry
- Farsightedness or nearsightedness
- Past eye injuries
- Thinner central corneal thickness
- Systemic health problems, including diabetes, migraine headaches and poor circulation
Your ophthalmologist will weigh all of these factors before deciding whether or not you need treatment for glaucoma, or whether you should be monitored closely as a glaucoma suspect. This means your risk of developing glaucoma is higher than normal and you need to have regular examinations to detect the early signs of damage to the optic nerve.
How is glaucoma treated?
As a rule, damage caused by glaucoma cannot be reversed. Eyedrops, laser surgery and surgery in the operating room are used to help prevent further damage. In other cases, oral medications may also be prescribed.
With any type of glaucoma, periodic examinations are very important to prevent vision loss. Because glaucoma can progress without your knowledge, adjustments to your treatment may be necessary from time to time.
Loss of vision can be prevented
Regular eye exams can help prevent unnecessary vision loss. Recommended intervals for eye exams are:
- Ages 20-29: Individuals of African descent or with a family history of glaucoma should have an eye examination every 3 to 5 years. Others should have an eye exam at least once during this period.
- Ages 30-39: Individuals of African descent or with a family history of glaucoma should have an eye exam every 2 to 4 years. Others should have an eye exam at least twice during this period.
- Ages 40-64: Every 2 to 4 years.
- Ages 65 or older: Every one to two years.