choroid


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choroid

 [kor´oid]
the middle, vascular coat of the eye, between the sclera and the retina. adj., adj choroid´al. It contains an abundant supply of blood vessels and a large amount of brown pigment that serves to reduce reflection or diffusion of light when it falls on the retina. Adequate nutrition of the eye is dependent upon blood vessels in the choroid.

cho·roid

(kor'oyd), [TA]
Portion of the middle or vascular layer of the eyeball lying between the pigment epithelium and the sclera and posterior to the other parts of the vascular layer, the ciliary body, and iris.
Synonym(s): choroidea [TA]
[G. choroeidēs, a false reading for chorioeidēs, like a membrane]

choroid

/cho·roid/ (ko´roid)
1. the middle, vascular coat of the eye, between the sclera and the retina.choroid´al
2. resembling the chorion.

choroid

(kôr′oid′) or

chorioid

(kôr′ē-oid′)
n.
The dark-brown vascular coat of the eye between the sclera and the retina. Also called choroid coat, choroid membrane.
adj.
1. Resembling the chorion; membranous.
2. Of or relating to the choroid.

choroid

[kôr′oid]
Etymology: Gk, chorion + eidos, form
a vascular layer of tissue between the retina and the sclera of the eye that supplies blood to the outer retina.

choroid

noun The highly vascularised and pigmented nutrient middle layer of the eye, located between retina and sclera (the tapetum is an iridescent layer in the choroid of some eyes); part of the uvea.

cho·roid

(kōr'oyd) [TA]
The middle vascular tunic of the eye lying between the retina and the sclera.
Synonym(s): choroidea [TA] .
[G. choroeidēs, a false reading for chorioeidēs, like a fetal membrane]

choroid

The densely pigmented layer of blood vessels lying just under the retina of the eye, contributing to its fuel and oxygen supply and optical efficiency.

choroid

  1. a layer behind the retina of the vertebrate eye which contains blood vessels and pigment.
  2. resembling the CHORION.

Choroid

The part of the uveal tract behind the ciliary body. The choroid underlies and nourishes the retina and absorbs scattered light.
Mentioned in: Uveitis

choroid

the middle, vascular coat of the eye, between the sclera and the retina.
It contains an abundant supply of blood vessels and a large amount of brown pigment which serves to reduce reflection or diffusion of light when it falls on the retina. Adequate nutrition of the eye is dependent upon blood vessels in the choroid. See also tapetum, lamina cribrosa, lamina basilaris, vascular lamina.

choroid ependyma
the ependymal cells which embrace choroid vessels to make up the choroid plexus.
choroid inflammation
choroid plexus
see choroid plexus.
References in periodicals archive ?
The choroid is one of the most highly vascularised tissues in the body, located between Bruch's membrane and the sclera.
Newly developed software for SD-OCT that uses an 830 nm infrared light source has increased our ability to image the choroid.
The retinal pigment epithelium is firmly adherent to the choroid and, in diurnal birds, it is rich in melanin granules, (5) hindering the ophthalmoscopic examination.
Selection of surgical technique for retinal detachment with coloboma of the choroid.
Fiona Doetsch at the Biozentrum of the University of Basel has now shown that the choroid plexus is a key component of the stem cell niche, whose properties change throughout life and affect stem cell behavior.
These areas are characterized by absence of pigmentation in RPE and in choroid, causing the white sclera to become visible between choroidal blood vessels (Janssens, 2002).
Faivre, in 1854 and Luschka, in 1855 were the first researchers to suggest that the choroid plexus is the source of CSF (3,29).
Non-Infectious Uveitis is an inflammatory process affecting the retina and/or the choroid layer of the eye.
When administered topically, drug concentrations in the retina and choroid are many-fold lower than the tear fluid.
Hanna was diagnosed with choroid plexus carcinoma - a cancer that presents as a fast-growing brain tumour.
The map catalogs more than 4,000 proteins in each of three areas of the choroid.
Researchers from University of Iowa developed a most detailed map to date of the abundance of thousands of proteins in the choroid, a region of the human eye long associated with blinding diseases.