Glaucoma refers to a group of eye conditions that lead to damage to the optic nerve. This nerve carries visual information from the eye to the brain. It is the second leading cause of blindness in the world and the leading cause of preventable blindness. January is National Glaucoma Awareness Month and a time to bring attention to a disease that can cause significant vision loss over time.
In the United States, 2.7 million people over the age of 40 have glaucoma but half of those people are unaware they have the disease. “Glaucoma steals sight gradually and once vision is lost, it is permanent,” says Mitchell Strand, MD, Touchstone Health HMO chief medical officer. “The best way to protect your sight and stop the progress of the disease is with early detection through regular eye examinations.”
In most cases of glaucoma, there is an increase in pressure inside the eye known as intraocular pressure (IOP). The flow of the fluid in the chambers of the eye between the cornea and the lens is restricted and the increased pressure in the eye eventually causes damage to the optic nerve.
There are four major types of glaucoma:
- Open-angle (chronic) glaucoma: This is the most common type of glaucoma. An increase in eye pressure occurs painlessly and slowly over time. The pressure pushes on the optic nerve.
- Angle-closure (acute) glaucoma: This type occurs when the exit of fluid is suddenly blocked. It causes quick, sever and painful rise in eye pressure. This type is an emergency and you should see your doctor immediately.
- Congenital glaucoma: This type is present at birth and is caused by abnormal eye development.
- Secondary glaucoma: This type is caused drugs such as corticosteroids or eye diseases such as uveitis, systemic diseases or trauma.
Damage to the optic nerve causes the field of vision to become impaired and can eventually cause blindness. Blind spots appear in certain areas of vision. Adjusting to change in lighting can become more difficult. These changes may not be immediately noticeable because central vision is not affected from the start. By the time the first symptoms appear, damage is usually extensive.
While glaucoma can affect anyone, some groups are at a higher risk for developing the disease including African Americans; people over the age of 60; having family members with the disease; Hispanics in older age groups; Asians; steroid users; and those with previous eye injury.
A complete eye exam is needed to diagnose glaucoma. Your doctor will develop a treatment plan to care for the disease. Treatment can manage symptoms, reduce eye pressure and stop or slow the damage to the optic nerve.
All adults should have a complete eye examination before the age of 40 or sooner if you have risk factors for glaucoma. Early detection of the disease can prevent or slow damage to the optic nerve and help maintain healthy eyesight for years to come.