Myopia (Near Sightedness)

A person with myopia needs to wear glasses in order to see things far away but can usually see things close by without the aid of glasses. The strength of the glasses needed in order for the person to see clearly is described in diopters. The higher the diopter power needed to correct the vision, the greater the amount of myopia. If greater than six diopters of correction are required to focus the light correctly on the retina, this condition is sometimes referred to as high myopia.

Within the retina is a small area known as the macula. The macula is the portion of the retina responsible for detailed vision and color vision. The remainder of the retina is involved in side vision and night vision. Some people with high myopia develop damage to their macula known as myopic macular degeneration. This damage is thought by some to occur because of thinning or stretching in the macula caused by slow continuous enlargement of the eye. Protective eyewear is also very important, especially when a person with high myopia engages in sports or other activities which exposes the eyeball to direct trauma.

A potential problem occurring in people with myopia is retinal tears or breaks that can lead to a retinal detachment. The peripheral retina can sometimes become torn. When this happens fluid from inside the eye can go through the tear leading to a retinal detachment. In a retinal detachment the retina becomes separated from its blood supply and permanent damage to this important light sensing membrane begins to occur. If the retina is detached it can often be reattached surgically with some return of vision. If a retinal tear or break is discovered before a retinal detachment occurs, it can be treated with either laser photocoagulation or cryotherapy. These two treatments involve causing a scar to form around the hole or tear thus sealing it. Once the retinal tear or break is sealed, there is less of a chance of a retinal detachment occurring.

The four warning signs of a retinal detachment are:

1. Flashes of lights.

2. Dark floaters (spots which move with eye movement and are seen under normal lighting conditions).

3. A curtain of darkness or a persistent dark area in the field of vision.

4. Blurriness of vision that does not go away with blinking.

If you should experience any of these four warning signs, you should contact your eye doctor immediately for examination.

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