myopia /my·o·pia/ (M) (mi-o´pe-ah) nearsightedness; ametropia in which parallel rays come to a focus in front of the retina, vision being better for near objects than for far.myop´ic 
curvature myopia,
myopia (M) [mi-o´pe-ah]
)
Myopia: error of refraction in a myopic eye (A), contrasted with normal refraction in an emmetropic eye (B).
curvature myopia myopia due to changes in curvature of the refracting surfaces of the eye.
index myopia myopia due to abnormal refractivity of the media of the eye.
malignant myopia , pernicious myopia progressive myopia with disease of the choroid, leading to retinal detachment and blindness.
progressive myopia myopia increasing in adult life.
| curvature myopia n. Myopia due to refractive errors in the corneal curvature. |
curvature myopia,
a type of nearsightedness caused by refractive errors associated with an excessive curvature of the cornea.
myopia (M) [mi-o´pe-ah]
a defect of vision consisting of an error of refraction in which rays of light entering the eye parallel to the optic axis are brought to a focus in front of the retina, so that vision for near objects is better than for far. This results from the eyeball being too long from front to back. Called also nearsightedness. adj., adj myop´ic.
Myopia generally appears before the age of 8, often becoming gradually worse until about the age of 20, when it ceases to change much. In later years the nearsighted person may find he or she can read comfortably without glasses. In children the most frequent symptoms of myopia are attempts to brush away blurriness, frequent rubbing of the eyes, and squinting at distant objects. Myopia can almost always be corrected with eyeglasses or contact lenses. Surgical procedures to correct it include radial keratotomy, photorefractive keratectomy, and lasik.
Myopia generally appears before the age of 8, often becoming gradually worse until about the age of 20, when it ceases to change much. In later years the nearsighted person may find he or she can read comfortably without glasses. In children the most frequent symptoms of myopia are attempts to brush away blurriness, frequent rubbing of the eyes, and squinting at distant objects. Myopia can almost always be corrected with eyeglasses or contact lenses. Surgical procedures to correct it include radial keratotomy, photorefractive keratectomy, and lasik.
Refraction and correction in myopia. From Ignatavicius and Workman, 2000.
curvature myopia myopia due to changes in curvature of the refracting surfaces of the eye, especially of the cornea.
index myopia myopia due to abnormal refractivity of the media of the eye.
malignant myopia (pernicious myopia) progressive myopia with disease of the choroid, leading to retinal detachment and blindness.
progressive myopia myopia that continues to increase in adult life.
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