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| Myopia (Nearsightedness) | Nearsightedness, or myopia, is a usual problem related with vision that affects approximately one-third of the population. People, who have nearsightedness, don’t see well distant located objects, highway signs but objects located at a close distance and activities performed at a close distance such as reading or sewing can be seen very well. People with myopia sometimes have headaches, fatigue or eyestrain; they sometimes squint while driving or playing sports. People who wear glasses or contact lenses and have such symptoms should have their eyes examined and have new glasses or lens prescribed.
Myopia appears when the eyeball is a little bit longer comparing with common from front to back. It is the result of light rays to be focused at a point in front of the retina, rather than directly on its surface.
People, who have myopia, find far objects to be blurry, but closer objects are seen much better. The nearsighted eye is longer than normal. Incoming light is not focuses directly on the retina, but in front of it.
Nearsightedness can be an inherited vision problem that dates from the childhood. Nearsightedness can be treated, but usually it may even get worse. Such phenomenon is called myopic creep.
 The problem of farsighted people can be solved with glasses, contact lenses or refractive surgery. It is recommended for farsighted people to wear glasses or contact lenses all the time, or only when it is required to see something at a distance at such activities as driving, seeing a chalkboard or watching a film. Nearsighted people wear glasses or contact lenses with negative number. The stronger lenses have the higher numeral.
Refractive surgery is able to lessen or even get rid you of the necessity to wear glasses or contacts. Usually the procedures are conducted with an excimer laser. In photorefractive keratectomy, or PRK, the laser takes away a layer of corneal tissue, which flattens the cornea and helps light rays to focus closer to or even on the retina. In laser-assisted in situ keratomileusis (LASIK) known as the most usual refractive procedure — a flap is cut through the top of the cornea, a laser takes away some corneal tissue, and then the flap is dropped back into place.
According to orthokeratology, known as a non-surgical procedure, one should wear special contact lenses that have an ability to reshape the cornea slowly and gradually with the purpose of myopia correction. With the lens’ removal, the cornea gradually obtains the new shape, making possible a clear vision without lenses.
Orthokeratology or corneal refractive therapy (CRT), that got approval by the FDA in 2002, cornea-shaping lenses can be worn at night, making possible to have daytime vision without wearing contacts or glasses.
Mild myopia can also be corrected with such surgical procedure as the implantation of plastic corneal rings, making possible the change of the cornea. The rings may be removed if any problem arises or if there is prescription change. It is possible to leave them in place temporally.
Nearsightedness can be easily corrected with glasses, contacts or vision surgery. But in rare cases of severe myopia it is regarded as pathologic.
Pathologic, or degenerative, myopia usually develops by age 12 in people who have unusually elongated eyeball. About two percent of Americans suffer from degenerative myopia. The stretching of the eyeball can be worse with age, and can lead to a progressive and severe loss of vision. The problem is regarded as an abnormal growth of new blood vessels (neovascularization) beneath the macula.
It was researched that nearsighted people are usually more educated comparing with people with good vision. The fact can be explained with the stress on the eyes that is the result of extensive reading. Pathologic, or degenerative, myopia usually corrected with the strongest possible glasses. Laser treatment is not usually helpful, it can only worsen the situation. In 2001, the injectable photosensitive drug Visudyne (verteporfin) was approved by the FDA to be used along with non-thermal laser application as a treatment for the neovascularization in pathologic myopia. Such treatment stabilized or improved vision in 72 percent of patients after one year, versus 44 percent on placebo.
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