myopia

myopia
/muy oh"pee euh/, n.
1. Opthalm. a condition of the eye in which parallel rays are focused in front of the retina, objects being seen distinctly only when near to the eye; nearsightedness (opposed to hyperopia).
2. lack of foresight or discernment; obtuseness.
3. narrow-mindedness; intolerance.
[1685-95; < NL < Gk myopía, equiv. to myop- (s. of mýops) near-sighted, lit., blinking (mý(ein) to shut + óps EYE) + -ia -IA]

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▪ visual disorder
also called  nearsightedness  

      visual abnormality in which the resting eye focuses the image of a distant object at a point in front of the retina (the light-sensitive layer of tissue that lines the back and sides of the eye), resulting in a blurred image. Myopic eyes, which are usually longer than normal from front to rear, are somewhat more susceptible to retinal detachment than are normal or farsighted eyes. Severe myopia can be associated with other eye problems as well, most of which affect the retina or the choroid (i.e., pathologic blood vessel growth from the choroid).

      Myopia can be corrected by concave lenses. Today, however, the use of LASIK (laser-assisted in situ keratomileusis) surgery has become common. In this procedure a hinged flap is made in the outer corneal tissue and lifted out of the way to allow an excimer laser (an ultraviolet chemical laser; also called an exciplex laser) to reshape the underlying tissue. The natural adherence properties of the replaced corneal flap negate the need for stitches. LASIK surgery is often preferred to photorefractive keratectomy (PRK), another type of laser-based surgery used to reshape the cornea.

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Universalium. 2010.

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  • myopia — (n.) short sightedness, 1727, medical Latin, from Late Gk. myopia near sightedness, from myops near sighted, lit. closing the eyes, from myein to shut (see MUTE (Cf. mute) (adj.)) + ops (gen. opos) eye (see EYE (Cf …   Etymology dictionary

  • myopia — [mī ō′pē ə] n. [ModL < Gr myōpia < myōps: see MYOPE] 1. an abnormal eye condition in which light rays from distant objects are focused in front of the retina instead of on it, so that the objects are not seen distinctly; nearsightedness 2.… …   English World dictionary

  • Myopia — My*o pi*a, n. [NL. See {Myope}.] (Med.) Nearsightedness; shortsightedness; a condition of the eye in which the rays from distant object are brought to a focus before they reach the retina, and hence form an indistinct image; while the rays from… …   The Collaborative International Dictionary of English

  • myopia — ► NOUN 1) short sightedness. 2) lack of foresight or intellectual insight. DERIVATIVES myopic adjective. ORIGIN from Greek muein shut + ps eye …   English terms dictionary

  • Myopia — For other uses, see Myopia (disambiguation). Myopia Classification and external resources ICD 10 H …   Wikipedia

  • Myopia — Klassifikation nach ICD 10 H44.2 Degenerative Myopie/Maligne Myopie H52.1 Myopie H52.5 Akkommodationsspasmus …   Deutsch Wikipedia

  • Myopia — Este artículo o sección necesita referencias que aparezcan en una publicación acreditada, como revistas especializadas, monografías, prensa diaria o páginas de Internet fidedignas. Puedes añadirlas así o avisar al autor princi …   Wikipedia Español

  • Myopia — Nearsightedness, the ability to see close objects more clearly than distant objects. Myopia can be caused by a longer than normal eyeball or by any condition that prevents light rays from focusing on the retina. Most forms of myopia can be… …   Medical dictionary

  • myopia — Ametropia Am e*tro pi*a, n. [Gr. ? irregular + ?, ?, eye.] (Med.) a visual impairment resulting from faulty refraction of light rays in the eye. Subtypes include {myopia} {astigmatism} and {hyperopia}. {Am e*trop ic}, a. [1913 Webster +PJC] …   The Collaborative International Dictionary of English

  • myopia — noun Etymology: New Latin, from Greek myōpia, from myōp , myōps Date: circa 1752 1. a condition in which the visual images come to a focus in front of the retina of the eye resulting especially in defective vision of distant objects 2. a lack of… …   New Collegiate Dictionary

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