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emmetropia |
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emmetropia /em·me·tro·pia/ (em″ĕ-tro´pe-ah) a state of proper correlation between the refractive system of the eye and the axial length of the eyeball, rays of light entering the eye parallel to the optic axis being brought to focus exactly on the retina. Symbol E.emmetrop´ic
emmetropia [em′ətrō′pē·ə] Etymology: Gk, emmetros, proportioned, opsis, vision a state of normal vision characterized by the proper relationship between the refractive system of the eyeball and its axial length. This correlation ensures that light rays entering the eye parallel to the optic axis are focused exactly on the retina. Compare amblyopia, hyperopia, myopia. emmetropic, adj. emmetropia proper coordination of the refractive system and the focal length of the eyeball so that the focused image falls exactly on the retina.
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. How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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In double-masked, placebo-controlled testing among both myopic and emmetropic patients, the iZon Wavefront-Guided Lens demonstrated a significant improvement in visual acuity, low contrast visual acuity and mid-frequency contrast sensitivity," said Dreher. At the debut, Ophthonix's Professional Advisors, a group of renown and influential doctors, presented clinical data on the Ophthonix lens, demonstrating significant vision improvement in myopic, emmetropic and LASIK patients. |
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