choroid


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Related to choroid: choroid coat, choroid plexus, ciliary body, optic disk, Choroid Plexus Carcinoma

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 ?
Aquaporin 1 is mainly expressed in the apical pole of the choroid plexus epithelial cells.
Pars plana vitrectomy and retinotomy were performed to remove subretinal tissue, which showed that there was leukemic infiltration in the choroid and concurrent bone marrow relapse (13).
External beam irradiation for choroid metastases: identification of factors predisposing to long term sequelae.
Occurrence of apoptosis in the choroid plexus epithelial cells was from other observations in the treatment group compared with the control group.
Papillary thyroid carcinoma with an uncommon spread of hematogenous metastases to the choroid and the skin.
Parasagittal: lateral ventricle, choroid plexus, periventricular area, cortex.
2) The physiologic calcifications of the choroid plexus (Figure 2) are very common after the age of 40 years.
It's hard for mothers to get over the idea of a cyst in the fetal brain when they hear that it is marginally associated with chromosomal abnormalities, for example, despite physician counseling that isolated choroid plexus cysts are not associated with Down syndrome and resolve in essentially all cases, she said.
Details of TB diagnosis included: organ biopsy (6) (transbronchial lung, bone marrow, skin or liver biopsy), lymph node biopsy (3), and observation of choroid tubercles on opthalmoscopy (1) and/or response to anti-tuberculosis therapy (6).
Another patient died about 4 months into the study after presenting with fever, seizures, and asymmetric paraparesis; the autopsy revealed infarction at the right choroid plexus and cerebral and cerebellum hemispheres, associated with a subarachnoid hemorrhage, the investigators reported.
The OCT scan revealed marked retinal atrophy with cystic changes, overlying atrophy of the retinal pigment epithelium, and increased reflectivity of the choroid.
Because of their accumulation in the choroid plexus (the blood-cerebrospinal fluid barrier), cadmium and lead have also been connected with neurotoxicity and neurological disorders, which are often associated with elevated oxidative stress and/or inefficient repair responses (Zheng 2001).