Glaucoma is a disease that causes damage to the optic nerve, which is the nerve that connects the eye with the brain. When enough damage has occurred, it results in loss of peripheral vision. If it becomes advanced it can even cause loss of central vision and blindness. In the most common types of glaucoma, the disease usually progresses slowly over many years. Risk factors for glaucoma include advancing age, African-American race, a family history of glaucoma, and increased pressure in the eye.
Many people think that eyes with glaucoma always have high pressure. This is not always the case. Some optic nerves are especially vulnerable to damage and can sustain damage even at normal pressure. This is call Normal Tension Glaucoma. There are other people who have elevated pressure in the eye, but have nerves that are resistant to damage, and do not develop glaucoma. These people are said to have Ocular Hypertension and need to be observed, but do not always need to be treated. Currently the only treatment for all of these conditions is to lower intraocular pressure, even if it is currently normal.
How does a person know if they have glaucoma? Glaucoma is often called “the sneak thief of sight,” because there are no symptoms in the early stages. By the time a person has noticeable symptoms, such as reduced peripheral vision, their optic nerve has already suffered significant damage. This damage cannot be reversed. The goal of glaucoma treatment is to prevent further damage and to stop the progression of vision loss. Because of this, it is important to have an exam with an eye care professional to look for signs of glaucoma. This is even more important for people in a high risk group such as anyone over 60, African-Americans over 40, or anyone having a family history of glaucoma.
Your eye doctor can determine if you at risk for glaucoma by doing a complete eye exam. During the exam if intraocular pressure is high or the optic nerve has changes consistent with glaucoma, then further specialized testing is needed. This may include a computerized peripheral vision test and use of an imaging device to detect optic nerve damage. Sometimes, your doctor may be able to diagnosis glaucoma after performing these initial tests. However, if the tests have borderline results, a patient may be diagnosed as a “glaucoma suspect,” meaning there is not enough evidence to start treatment, but it is important to continue monitoring closely.
Why is it important to detect glaucoma early? Because there are effective treatments such as eye drops or an outpatient laser procedure which can lower eye pressure and prevent glaucoma progression. Since glaucoma damage cannot be reversed, it is important to catch this disease in its early stages, in the hopes that with effective early treatment, patients may never reach the point where their vision is noticeably impaired.