What's the difference between short sightedness and long sightedness?
Short sightedness and long sightedness are two very common — and very different — types of vision conditions. Both are refractive errors, or abnormalities of the eye that affect its ability to focus light on the retina.
The medical term for shortsightedness is myopia. This occurs when light entering the eye does not focus properly on the retina, the membrane that lines the back of the eyeball. Instead, the light falls short — usually because the eyeball has grown too long. As a result, distant objects appear blurry. Close-up vision, on the other hand, is not affected.
Long sightedness, or hyperopia, is somewhat the opposite of short sightedness. It usually is caused by an eyeball that's too short, which causes light to come to a focus behind the retina instead of directly on it.
Typically, long sightedness makes close objects appear to be out of focus, while distant objects remain clear. But high amounts of hyperopia may cause objects at all distances to be blurry.
Mild cases of long sightedness might not affect vision at all but cause headaches when reading or doing other close work.
Interestingly, children usually are born longsighted. In most cases, this early childhood hyperopia decreases as the eyeball lengthens with normal growth and development.
Short sightedness, however, usually develops during childhood, worsens during adolescence and stabilises during young adulthood.
Short sightedness and long sightedness share some common symptoms, including headaches, eye strain, squinting to see clearly, and eye fatigue.
Experiencing any of these symptoms is an indication that a comprehensive eye exam with an optician is needed to determine a diagnosis and treatment options.
Treatment for shortsightedness and longsightedness
Many people find that their short sightedness or long sightedness stabilises once they’re in their twenties.
When there is no more change in refractive error, LASIK and PRK are two surgical procedures that can permanently correct myopia or hyperopia by reshaping the cornea so light comes to a clear focus on the retina.