Glaucoma is called the “sneak thief of sight” because it can be present for many years, gradually destroying your sight without causing any symptoms. Generally, glaucoma is caused by an abnormally high pressure inside your eye, which, if untreated, can result in slowly progressive loss of vision. Pressure is measured by an instrument called a tonometer which the doctor places on the surface of your eye. In most cases of glaucoma, the pressure increase does not cause pain or discomfort, so you may not be aware that you have glaucoma. Evaluation of damage caused to vision by glaucoma can be made only by examining the insides of your eyes and by charting the visual fields of your eyes. There are many forms of glaucoma, some of which are treated with eye drops and pills,
and others which require surgery. Various types of lasers can be used to treat glaucoma under certain circumstances. Some people are at high risk for glaucoma.

If you are African American, have diabetes, blood vessel disease, a family history of glaucoma, or a history of eye injury or inflammation, then your risk of having glaucoma will be higher. Regardless of risk category, you should be examined for glaucoma throughout your life at intervals prescribed by your doctor. Sight loss due to glaucoma may be prevented by early treatment. Remember, however, that vision lost to glaucoma cannot be restored by medical or surgical treatment. By contrast, with decreased vision due to cataract, removal of the hazy lens will ordinarily restore sight.