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The oriental population has a high percentage of short sighted people. The condition of short sightedness is known as myopia. This is from the Greek word "myos" which means "I close my eye". Apparently, the ancient Greeks observed that myopic people tend to "squint" their eyes to gain focus of the object that they are interested in. The high percentage of myopes in our oriental population is due to the dominant polygene. For instance, a parent who has myopia will likely to pass this gene to his(her) child, irrespective of the other parent. In this article, we will concentrate on the characteristics of myopia after birth, as science has not found a way to deal with the myopic polygene at the moment.

Typically, myopia occurs when the combined focusing part of the eye (mainly the cornea and the crystalline lens) places the focus point of a distant object in front of the retina. This can happen in the following conditions: (1) cornea and/or crystalline lens too powerful; (2) eyeball too long; (3) an increase in the refractive index of the cornea and/or crystalline lens; (4) prolapse of the crystalline lens; (5) the cornea steepens in keratoconus.

Myopia can be classified into the following 3 categories: (1) low myopia with power from plano to -3.00D; (2) medium myopia with power between -300D to -6.00D; (3) pathological myopia with powers beyond -6.00D. We may also classify pathological myopia according to the rate of increase of power.

Common causes of myopia include excessive muscular action of the ciliary body. This is common amongst students doing a lot of close work. A less common condition known as pseudo-myopia is a result of the hysterical spasm of the ciliary body. Yet another commonly encountered condition is cataract where the refractive index of the crystalline lens increases dramatically. Keratoconus, not as rare as one thinks, has the cornea steepens and/or distorts dramatically.

So why control? Well, apart from the fact that no one likes to be a high myope who wears thick powered lenses, we also consider the rate of increase of myopia. So, it is a matter of how much myopia at the present as well as what kind of powers you are likely to have in the future: 6 months, a year, 2 years or 3 years from now. The good news is myopia can be controlled by spectacles as well as contact lenses. We are not talking about laser surgery which is a form of correction where powers are not exactly zero in many cases, besides they are not a guarantee that your myopia cannot increase in the future.

Numerous control techniques have been advocated. In many cases a correctly fitted pair of spectacles presents a good way of control. This involves a good prescription and a very strict method of making up the pair of spectacles. In other cases, contact lenses also control myopia very well. Again, a good prescription and well fitted contact lenses are paramount. Each individual is unique, so proper control can only be established after a thorough eye examination.