About Glaucoma National Eye Institute Glaucoma Home Page Glaucoma Assoc. There are four major influences that are considered in determining if a patient has glaucoma. The most common type of glaucoma is primary open angle glaucoma. This is usually completely painless and most patients are not aware that they have it unless they undergo a thorough eye examination.
Loss of vision is usually very gradual and occurs over many years.
Top of Page A number of factors increase the risk of damage from glaucoma. It is believed that something is wrong with the ability of the cells in the trabecular meshwork to carry out their normal function, or there may be fewer cells present, as a natural result of aging. Some believe it is due to a structural defect of the eye's drainage system. Others believe it is caused by an enzymatic problem. A pressure of 22 is considered to be suspicious and possibly abnormal.