Orthokeratology is a process that reshapes the cornea using hard contact lens so as to correct or reduce refractive problems such as astigmatism, hyperopia and myopia. This is a non-surgical and non-invasive process that involves wearing specific lenses each night so as to achieve ideal corneal shape. This allows the person suffering the vision problem to be free of spectacles or glasses throughout the day. Those with high myopic error have seen some reduction in the error while teenagers how are recently myopic can help stabilize the progression of the vision defect. But the person needs to visit the optometrist many times in a period of about 6 months.
Myopia or nearsightedness is a condition where a person has trouble seeing things that are far away. The eye finds it difficult to focus the light directly on the retina since the physical length of the eye is greater than the optical length. Such a person suffering myopia finds distant objects blurred and might need to squint to see them clearer. Symptoms of myopia are eyestrain and sometimes headache. This is quickly noticed in school going children who have difficultly reading the blackboard. In fact myopia worsens during the growth years and then stabilizes after the teens. Regular eye tests with refraction test help in diagnosing the degree of refraction lens needed. Spectacles or contact lens are prescribed to correct the focus of the light image on the retina thereby producing a clear image. LASIK is also performed to correct myopia. Orthokeratology involves usage of special rigid contact lenses to flatten the cornea to reduce myopia.
Astigmatism is a refractive error caused by abnormal curvature of the cornea thereby causing blurred vision. It might occur along with myopia or hyperopia. Some persons suffer astigmatism from birth. Astigmatism can be identified with the routine eye tests. Visual acuity test, keratometry and refraction might be undertaken to diagnose the astigmatism or any other vision problem. Mild astigmatism is not usually corrected. Corrective lens is prescribed after noting the extent and axis of the astigmatism. Orthokeratology is undertaken to implant specially designed rigid contact lenses to gradually reshape the curvature of the cornea. Laser surgery can be done to alter the corneal shape.
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Collection of Pages - Last revised Date: August 19, 2018