emmetropia


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emmetropia

 [em″ĕ-tro´pe-ah]
the ideal optical condition, parallel rays coming to a focus on the retina. adj., adj emmetrop´ic.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

em·me·tro·pi·a

(em'ĕ-trō'pē-ă), Do not confuse this word with ametropia.
The state of refraction of the eye in which parallel rays, when the eye is at rest, are focused exactly on the retina.
[G. emmetros, according to measure, + ōps, eye]
Farlex Partner Medical Dictionary © Farlex 2012

emmetropia

(ĕm′ĭ-trō′pē-ə)
n.
The condition of the normal eye when parallel rays of light are focused exactly on the retina and vision is perfect.

em′me·trop′ic (-trŏp′ĭk, -trō′pĭk) adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

em·me·tro·pi·a

(em'ĕ-trō'pē-ă)
The state of refraction of the eye in which parallel rays, when the eye is at rest, are focused exactly on the retina.
[G. emmetros, according to measure, + ōps, eye]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
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EMMETROPIA, MYOPIA, HYPEROPIA
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EMMETROPIA, MYOPIA, HYPEROPIA
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EMMETROPIA, MYOPIA, HYPEROPIA

emmetropia

(em?e-tro'pe-a)
The normal condition of the eye in refraction in which, when the eye is at rest, parallel rays focus exactly on the retina.
See: illustration; astigmatism; myopia
Medical Dictionary, © 2009 Farlex and Partners

emmetropia

The state of the normal eye, with relaxed ACCOMMODATION, in which light rays from a distance (parallel rays) focus accurately on the retina giving perfect vision.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

emmetropia

The refractive state of the eye in which, with accommodation relaxed, the conjugate focus of the retina is at infinity. Thus, the retina lies in the plane of the posterior principal focus of the eye and distant objects are sharply focused on the retina. This is the ideal refractive state of the eye. Note: the concept of emmetropia is not simple because accommodation is not inactive when fixating at distance (tonic accommodation). In fact, some authors consider hypermetropia of up to 1.00 D, in a pre-presbyope, as emmetropia. See resting state of accommodation; ametropia; conjugate distances.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann
References in periodicals archive ?
In our study, the mean Q values of the nasal cornea among different refractive groups of children were significantly different, and so was that of the temporal cornea between the adult emmetropia group and myopia group (p < 0.05).
Refractive error rates n % Expected % p Myopia 20 10.2 65.3 Emmetropia 36 18.4 65.3 0.001 (**) Hypermetropia 140 71.4 65.3 Chi-square test, (**) p<0.01 Table 4.
in their observed a 0.037 mm increase in axial length in emmetropia and 0.058 mm increase in myopia during accommodation.
Cats need higher diopteric strength IOL for restoration of emmetropia after removal of cataractous lens.
Our study is also one of the first to report the differences in ACD among different refractive groups (myopia, emmetropia, and hyperopia) within the same population in Asian children.
Most of these patients hope to get rid of glasses or contact lenses, but emmetropia was achieved in less than 50% cases.3 It has been noted in different studies that ophthalmic and systemic co-morbidities have a significant role in post-op refractory surprises.4 Another cause is incorrect lens position.5
Since the choroidal thickness was reported to be greater in the hyperopia than in emmetropia and myopia children [35], one of the children in our study had high myopia of -10.75 D, in which the measured subfoveal choroidal thickness was 143 [micro]m, which might explain the different result.
Breeds used in activities requiring highly visual functioning were found to be closer to emmetropia.
A total of 100 retinal images were chosen and further classified into two groups which are moderate to high myopia and emmetropia groups based on the spherical equivalent refraction (SER) and other inclusion criteria.
The inlay eye is treated with LVC first typically aiming for slight myopia (-0.75 D) rather than emmetropia with the corneal inlay implantation, undertaken as a second procedure once the refraction is stable.
We aimed for a postoperative refractive goal of +6 for a 1-year-old, +5 for a 2-year-old, +4 for a 3-year-old, +3 for a 4-year-old, +2 for a 5-year-old, +1 for a 6-year-old, and emmetropia for older ages.