COMPUTER
VISION SYNDROME
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Do you have tired or sore eyes? Headaches? Blurred vision? And general fatigue? If so, like millions of people, you may be suffering from a problem called Computer Vision Syndrome (CVS).
See the article on Computer Vision Syndrome from WTVH January 7, 2005
just click here 
The macula is
where light focuses after passing through the cornea, pupil, and lens. The
macula's function is to sense light, and create impulses that are sent through
the optic nerve to the brain the macula is responsible for central vision, and
your ability to see color, and fine detail when you look directly at an object.
Macular degeneration is a disease that affects the central vision. It is the
most common cause of vision loss among people over age 60. Macular degeneration
generally takes two forms. Dry, age-related macular degeneration affects 90% of
those with the disease. The earliest sign that macular degeneration is beginning
is the development of tiny areas in the macula called drusen. This form occurs
when the tissue of the macula thins over time. Since the dry form is simply a
matter of the macula wearing out with age the loss of central vision tends to be
gradual over the years. This form of the disease is more prevalent, but less
serious. Wet age-related macular degeneration affects 10% of those with the
disease. In this form, abnormal blood vessels grow underneath the retina. These
vessels may leak, and cause scarring, and loss of central vision if any of this
damage occurs within the macula, serious and rapid deterioration of the person's
Central vision can result. This form accounts for 90% of the most serious loss
of vision cases. The dry form of this disease may convert to a wet form at any
time. The wet form usually occurs in people who already have the dry form
Aging causes the vitreous gel to become less like a gel and more like a fluid. As the eye moves, liquefied vitreous also move around inside the vitreous cavity. This movement causes the vitreous to pull on the retina, and in time the vitreous can pull free and separate from the retina. This is called a posterior vitreous detachment. Pulling of the vitreous on the retina can cause flashes of light. We usually see this once a posterior vitreous detachment occurs. As the vitreous liquefies and pulls away from the retina it becomes condensed and stringy and forms strands. We see these strands and strings as they appear as spots, circles, jagged lines and irregular fine threads in the vision. They appear to float, and we call these vitreous floaters
Presbyopia affects everyone and usually begins to affect vision around age 40. Rays of light from near objects such as a printed page are divergent in nature and will come to a focus behind the retina. In order for this light to focus on the retina, accommodation occurs. During accommodation, the ciliary muscle contracts this contraction results in an increase in the curvature of the lens. Refocusing light back onto the retina. The aging process causes a gradual hardening of your lens, causing its inability to change shape. From age 40 onward, close work gradually becomes more difficult. This condition is called presbyopia.
Glaucoma is a disease that gradually steals sight without symptoms, pain, or warning. Typically characterized by high pressure within the eye, glaucoma can also occur in some cases with normal or low pressure in the eye. The eye is divided into two chambers, the anterior chamber, or the front compartment of the eye; and the posterior chamber, or the back compartment of the eye. In a normal, healthy eye, clear liquid, called the "aqueous humor," circulates continuously from the posterior chamber, through the pupil and into the anterior chamber. Produced by the ciliary body, this fluid cleans and nourishes the inside of the eye. The aqueous humor then leaves the eye through an opening in the trabecular meshwork. In an eye that has glaucoma; more fluid is produced than can be removed by the eye, which means the fluid builds up. This built-up fluid increases pressure in the anterior chamber of the eye. The increasing pressure in the anterior chamber eventually transfers to the rest of the eye. The optic nerve, the weakest area of the eye, is most vulnerable to damage from this elevated pressure. Continuous elevated pressure on the optic nerve will eventually damage the neural tissue that makes up the millions of nerve fibers that send visual impulses to the brain. Thinning and eventual destruction of neural tissue will cause changes in the appearance of the optic nerve. These changes are typically referred to as "cupping". It is this damage to the optic nerve that prevents light from getting to the brain. If light signals cannot reach the brain due to severe damage, a person can go blind.
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