macula lutea

macula lutea
/mak"yeuh leuh looh"tee euh/, pl. maculae luteae /mak"yeuh lee' looh"tee ee', mak"yeuh luy' looh"tee uy'/.
macula (def. 2b).
[1840-50; < NL: lit., yellow macula; see MACULA, LUTEOUS]

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      in anatomy, the small yellowish area of the retina near the optic disk that provides central vision. When the gaze is fixed on any object, the centre of the macula, the centre of the lens, and the object are in a straight line. In the centre of the macula is a depression, called the fovea, which contains specialized nerve cells that are exclusively of the type known as cones. Cones are associated with colour vision and perception of fine detail. Toward the centre of the macula there are no blood vessels to interfere with vision; thus, in this area, vision in bright light and colour perception are keenest.

      Age-related macular degeneration (ARMD) is a relatively common condition in people over the age of 50. There are two forms of ARMD, known as wet and dry. In wet ARMD new blood vessels form beneath the retina that are very fragile and prone to breakage and bleeding, thereby compromising central vision acuity. As a result, wet ARMD advances more quickly and is more severe than dry ARMD, which is characterized by the presence of drusen (tiny yellow deposits on the retina) and the loss of retinal pigment and may progress so slowly that it goes unnoticed. Both conditions reduce central vision but do not interfere with peripheral vision (see also visual-field defect (visual field defect)).

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Universalium. 2010.

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Look at other dictionaries:

  • mácula lútea — f. anat. Región de la retina de color amarillento y de forma irregular localizada en el polo posterior del bulbo; corresponde a la zona de mayor agudeza visual. Medical Dictionary. 2011. mácula lútea …   Diccionario médico

  • macula lutea — macula lutea, macular area macular area . A yellowish central area of the retina that is rich in cones. Syn: macula, yellow spot. [WordNet 1.5] …   The Collaborative International Dictionary of English

  • macula lutea — [lo͞ot′ē ə] n. [ModL, lit., luteous spot] an area of especially keen vision on the retina …   English World dictionary

  • macula lutea — noun a small yellowish central area of the retina that is rich in cones and that mediates clear detailed vision • Syn: ↑macula, ↑macular area, ↑yellow spot • Hypernyms: ↑area, ↑region • Part Holonyms: ↑ret …   Useful english dictionary

  • Macula Lutea — Ansicht des Augenhintergrundes bei der Augenspiegelung. Zentral der Gelbe Fleck, rechts die Papille [erscheint hier gelb] Position des Gelben Flecks Als Gelber Fleck (lat. Macula …   Deutsch Wikipedia

  • mácula lútea — Eng. Macula lutea Área pigmentada que se aprecia en oftalmoscopia al mismo nivel del disco óptico, en el centro del globo ocular, donde se localizan la mayor concentración de conos. Es el punto de mayor sensibilidad y agudeza visual. Mácula.… …   Diccionario de oftalmología

  • macula lutea — macula lu·tea lüt ē ə n, pl maculae lu·te·ae ē .ē, ē .ī a small yellowish area lying slightly lateral to the center of the retina that constitutes the region of maximum visual acuity and is made up almost wholly of retinal cones called also… …   Medical dictionary

  • macula lutea — mac•u•la lu•te•a [[t]ˈmæk yə lə ˈlu ti ə[/t]] n. pl. mac•u•lae lu•te•ae [[t]ˈmæk yəˌli ˈlu tiˌi, ˈmæk yəˌlaɪ ˈlu tiˌaɪ[/t]] oph macula 2), b) • Etymology: 1840–50; < NL: lit., yellow macula; see macula, luteous …   From formal English to slang

  • macula lutea — noun macula (yellow spot in the human eye) …   Wiktionary

  • macula lutea — noun (plural maculae luteae) Etymology: New Latin, literally, yellow spot Date: 1848 a small yellowish area lying slightly lateral to the center of the retina that constitutes the region of maximum visual acuity called also yellow spot …   New Collegiate Dictionary

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