Glaucoma results from a damage to the optic nerve. Usually the damage is from increased pressure in the eye. The damage to the eye is irreversible and glaucoma can lead to blindness.
The most common form, open-angle glaucoma, generally appears in middle age and seems to have a genetic component. In this type of glaucoma, vision loss occurs very gradually. One eye is often worse than the other. Other types of glaucoma are closed-angle glaucoma (a medical emergency) and congenital glaucoma (present at birth).
Secondary glaucoma is usually associated with another eye disease or disorder, such as a very mature cataract, uveitis, bleeding, eye tumor, or an eye injury.
How Do I know if I Have Glaucoma?
Tests for glaucoma are brief and painless. Your eye doctor will routinely measure intraocular pressure with a tonometer that you won’t feel after having numbing eye drops. Be certain to tell your doctor if you have ever had any prior refractive surgery, because it can artificially alter the eye pressure measurement. The mere presence of higher-than-normal eye pressure does not mean that you have glaucoma.
In fact, some patients with eye pressure low enough to usually be considered normal may actually have glaucoma, while others with elevated pressure may not have the disease. Elevated pressure in the eye without evidence of damage to the optic nerve is called ocular hypertension. Patients with this condition must be tested at regular intervals.
If glaucoma is suspected, your eye doctor will carefully inspect the appearance of the optic nerve for signs of damage. You will also have a visual field test that measures the sharpness of your peripheral vision (side vision) by using spots of light of different sizes and intensities. The doctor will take other measurements as well.