The glaucoma you may be missing
Sometimes normal eye pressures mask the condition.
Ever get an eye pressure measurement at the eye doctor's office? The doctor directs a probe or a puff of air at your cornea to find out if the pressure inside the eye is elevated, often a major sign of glaucoma. But increased eye pressure isn't always an accurate way to detect the condition. You can sometimes have normal eye pressure and still have glaucoma.
Types of glaucoma
The vision loss of glaucoma is caused by damage to the optic nerve. That's the nerve that sends electrical signals to the brain, which then interprets the signals as images. Nerve damage often results when pressure gets too high because of fluid buildup inside the eye. With the most common type of glaucoma, open-angle glaucoma, damage to the nerve is usually painless and occurs gradually. (With the less common closed-angle glaucoma, people can experience sudden pain and nausea.)