Glaucoma is a group of ocular diseases that can cause optic nerve damage and loss of vision.

The optic nerve carries the images that we see to the brain.  It is like an electric cable transmitting impulses to the brain.   The elevated pressure that is usually present in glaucoma, can damage the optic nerve and cause blind spots in a person's vision.  These blind spots usually develop so slowly that the patient is unaware of their presence.

What causes Glaucoma?

In most cases of glaucoma, the natural fluid that is produced in the eye (the aqueous humor) does not adequately drain out of the eye.  As a result, the fluid pressure increases inside the eye, causing damage to the optic nerve and loss of vision.

Are there different types of Glaucoma?

There are many different types of glaucoma but the two major types are: Primary Open Angle Glaucoma and Primary Closed Angle Glaucoma.

Primary Open Angle Glaucoma (also known as Chronic Open Angle Glaucoma)

This is the most common form of glaucoma.  In people over the age of 40, about 1% have Primary Open Angle Glaucoma. (Primary Open Angle Glaucoma is even more common and more severe in African Americans.)  This is a disease in which the drain pipes do not adequately transport the eye fluid (aqueous humor) out of the eye and into the blood stream.  Primary Open Angle Glaucoma generally progresses slowly without symptoms and causes a gradual loss of vision that is undectable without a visual examination.

Primary Closed Angle Glaucoma (also known as Angle Closure Glaucoma)

Primary Closed Angle Glaucoma is about one tenth as frequent as Primary Open Angle Glaucoma.  In Primary Closed Angle Glaucoma, the eye pressure goes up due to a blockage of the drainage area (called the "angle" of the eye) where the fluid enters the drain pipes.  Eye pressure may increase rapidly in Primary Closed Angle Glaucoma and causes eye redness, blurred vision, severe eye pain, brow ache or headache, rainbow colored halos around lights, and nausea and vomiting.   This is an eye emergency and requires prompt medical and surgical treatment to prevent serious and permanent damage to vision.

How is Glaucoma diagnosed?

Periodic comprehensive eye examinations with an eyecare provider are the best way to detect glaucoma.  During an examination, the intraocular pressure will be measured, the drainage area (angle) and the optic nerve will be examined, and a visual field or peripheral vision test conducted.  Some tests may not be necessary for every person.  These tests may need to be repeated regularly to diagnose and monitor glaucoma.

Who is at risk to develop Glaucoma?

Although ANYONE can develop glaucoma, many factors are involved in determining an individual's chances.  If a person is over 40 years old, is nearsighted, has a family member with glaucoma, has diabetes mellitus or vascular disease (high blood pressure, Raynauds phenomenon, migraine syndrome), there is a greater risk of developing glaucoma.  African Americans may have a seven times greater risk of glaucoma.

Can Glaucoma be cured and how is it treated?

In most cases, glaucoma can only be controlled and requires continuous monitoring to guard against vision loss.

Glaucoma is treated with both eye drops and occasionally with pills.   These medications decrease the eye pressure and help to prevent damage to vision.   Laser surgery can also be effective in the treatment of glaucoma.  In Primary Open Angle Glaucoma the drain pipes are treated with the laser to improve the drainage of the aqueous fluid and lower the eye pressure.  In Primary Closed Angle Glaucoma, laser treatment creates an opening in the iris which improves the flow of aqueous fluid to the area of drainage. Operating room microsurgery (or incisional scalpel surgery) is another treatment option for glaucoma.  Also called filtering surgery, this creates a new drainage channel for the aqueous fluid.  The fluid then drains into a reservoir (called a bleb) which is created in the tissues on the surface of the eyeball.  This helps to lower the eye pressure.

Loss of vision can be prevented!

Regular comprehensive eye examinations are the most effective way to detect glaucoma.  If an initial examination is normal, re-examinations are recommended every two to three years from 18-40 years of age, every two years from 41-60 years and annually for individuals over 61 years of age.  If there is a family member with glaucoma, African ancestry, a serious eye injury in the past, or if steroid medications are being used, eye examinations are recommended even more frequently.