Glaucoma Symptoms

"The Thief of Sight"

Within the U.S. glaucoma is the third largest cause of blindness -- one of the most common elderly issues. It is responsible for about 8 percent of loss of vision, and 11 percent of blindness overall. It is believed there are about 3 million Americans who have glaucoma. It is estimated that over half do not know it yet. Over 1 million already have vision impairment. Worldwide, approximately 6 million people are blind in both eyes from glaucoma. And of those who are legally blind over the age of 65, over 75 percent have glaucoma. In addition, studies show it is the largest cause of blindness in African Americans.

Glaucoma Causes

Have you ever had your eye doctor give you an eye pressure test? This test is called a tonometry. It’s recommended that anyone over age 40 receive this test about every 3 to 5 years. This is very important since beginning symptoms of glaucoma are not detected except through a glaucoma test. The doctor may send a small puff of air into your eye. Or give numbing drops and then gently tap the surface of your eye with a pen-like instrument. The purpose of the tonometry test is to measure your eye pressure, since faulty eye pressure is the main cause of glaucoma.

How is Your Eye Like a Sink?

Glaucoma causes are mainly due to an increase in pressure in the eye. If eye pressure is too low, the eye becomes softer. If it is too high, the eye becomes harder and puts pressure on the delicate optic nerve. The eye has a system of fluids, input for nourishment and maintenance. There is also a natural drainage system that channels the fluids into small blood vessels, which then take the fluids into the main bloodstream. This system is often compared to a faucet and a drain in a sink. The difference is, if a sink becomes clogged it can overflow. The eye cannot. So what happens if eye can’t drain nor overflow? This is the problem with the cause of glaucoma. Pressure builds up. It has nowhere to go so it presses against and damages the optic nerve.

The cause of glaucoma has to do with how it affects the optic nerve. This optic nerve is the main nerve in the eye, and is located in the back of the eyeball. This is what is responsible for sending images to the brain for the brain to interpret. We call this vision. It is vital that the eyeball maintain a certain range of pressure so the optic nerve can function correctly. If this pressure is upset, it affects the blood flow to the eye. The optic nerve is unable to function. Our vision is impaired. And it begins unseen and unfelt. See Before and After images to the right.

If damage is being done, how can it not be noticed?At first, glaucoma has no obvious symptoms. Once symptoms are noticed, it is too late, because vision loss has already started. However, elevated eye pressure on the optic nerve can be detected in an eye exam. If a person does not have regular eye exams, this could continue for years. Then the actual damage to the optic nerve usually starts as loss of peripheral vision – at the sides of the eye. Peripheral vision is not as noticeable. After time, if this is not detected and stopped, the central vision will be lost. Central vision is very noticeable.

Once damage to the optic nerve has occurred, it cannot be reversed. Blindness, to whatever degree, is permanent. Glaucoma usually affects both eyes, but one eye can be worse than the other.

Who is at Risk?

To know if you are at risk, read these main factors:

• History of glaucoma within family
• Sever myopia (nearsightedness)
• Aging
• Hypertension (high blood pressure)
• Diabetes

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