Table of Contents
Definition of Refractive Errors
Vision disorders in which a defect of the eye does not allow proper refraction of light. When the eye is longer than normal from front to rear, the lightwaves entering the eye focus short of the retina, resulting in myopia (nearsightedness). When the eye is shorter, the lightwaves that enter the eye focus behind the retina, resulting in hyperopia (farsightedness). An irregular surface or shape to the cornea may produce distortions of refraction, resulting in astigmatism.
The optometrist or ophthalmologist measures refractive errors using a refraction test. treatment is corrective lenses (eyeglasses or contact lenses) or refractive surgery. Refractive errors may change frequently during childhood, though usually stabilize by early adulthood. Severe refractive errors may be uncorrectable, notably myopia, resulting in functional or legal blindness.
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