Glaucoma & Assessment
Glaucoma is a group of eye diseases that results in a gradual loss of vision, and occurs without warning or symptoms. It is the second leading cause of blindness in the United States in people over 40 years old (macular degeneration is the first). Unfortunately, up to 50% of people who have glaucoma do not know that they have the eye disease.
Glaucoma leads to blindness by damaging the optic nerve. A common hallmark of this disease is an increased pressure in the eye, although not all types of glaucoma arise from high pressures. The pressure increase slowly damages the eye’s optic nerve and causes peripheral vision loss at first which can progress to loss of all vision.
When detected early, blindness from glaucoma is almost always preventable. Often there are no symptoms at first, but a comprehensive eye exam can detect early stages of glaucoma.
A decrease of blood flow or oxygen to the optic nerve can lead to glaucoma. This can be compared to shutting off the flow through a garden hose by squeezing the hose. When this occurs, nerve tissue is damaged, and the ability to transmit visual images to the brain is compromised. If this is allowed to continue, the nerve will die and blindness will result.
If you have any of these risk factors, you have a greater likelihood of developing glaucoma:
- Family history of glaucoma (10 times greater risk)
- High intraocular (eye) pressure
- Risk increases with age (although children can have glaucoma)
- Race (Afro-American)
- Thin corneas (central thickness of less than 555 microns)
- Suspicious looking optic nerves or nerve fiber layer
- High myopia
- Eye injury or surgery
- History of steroid use
- Migraine headache and peripheral vasospasm
- Sleep-related breathing disorder
If you are at risk, you should have your eyes examined every year. Your specialized exam for glaucoma will include a measurement of your eye pressure, visual fields, and nerve fiber layer, and a retinal photo.
There are many forms of glaucoma. The most common form is called Open Angle Glaucoma which usually related to high intraocular pressure. There’s also one form of glaucoma that is called low tension or normal tension where the pressure is not elevated. Acute (angle closure) Glaucoma is a much less common form and almost always involves one eye although the fellow eye has the same predisposition. It often develops rapidly, within 24 hours and is usually accompanied by severe pain and nausea. This type of Glaucoma is an emergency and must be treated immediately in order to minimize vision loss as well as save the involved eye.
There is no treatment to reverse the effects of glaucoma, but progression can be slowed down or prevented. The treatment goal in Glaucoma Therapy is to prevent further damage from occurring and to preserve the existing vision. This is accomplished through the use of eye drops, laser and in some advance cases, surgery. Early treatment can help protect your eyes against vision loss. The effectiveness of any Glaucoma Therapy in large part depends on your compliance to the treatment and keeping scheduled follow ups with us. Early detection is very important to prevent.
Assessing Risk Factors for Glaucoma
- 50% of glaucoma patients are undiagnosed.
- 50% of conventional eye exams miss glaucoma.
- Glaucoma can be detected 22 months earlier in 59% of cases and 79% earlier six months in advance by our Heidelberg Retinal Tomograph.
- 1/3 of all patients with primary open angle glaucoma have normal intraocular pressure, so the “eye pressure” test is not sufficient.
- A direct family member with glaucoma increases your risk by approximately 10X.
Level of Glaucoma Risk based on risk factors: If you get a score of 3 or higher in the table below, contact us for a comprehensive eye examination and a glaucoma evaluation at your earliest conveniences. People with a high score (at risk of glaucoma) should faithfully have eye checkups at the intervals recommended by their Optometrist. Everyone over 40 should have a comprehensive eye examination every two years, regardless of risk factors.
|Age||younger than 50 years||0|
|older than 75 years||3|
|Family History of Glaucoa||Negative or positive in non-first degree relative||0|
|Positive for parents||1|
|Positive for siblings||2|
|Last Complete Eye Exam||Within last two years||0|
|2-5 years ago||1|
|more than 5 years ago||2|
Level of Glaucoma Risk (Total Score)
|High||4 or greater|
|Low||2 or less|