Choroid

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Related to choroidal: choroidal artery, choroidal detachment, Choroidal Neovascularization

choroid

[′kȯr‚ȯid]
(anatomy)
The highly vascular layer of the vertebrate eye, lying between the sclera and the retina.

Choroid

 

the connective-tissue coat of the eye located between the retina and the sciera. It is through the choroid that metabolites and oxygen pass from the blood to the pigmentary epithelium and photoreceptors of the retina.

The choroid includes a suprachoroid layer facing the sciera, a layer of large veins, a layer of arteries and veins, the choriocapil-laris, and Bruch’s membrane. The suprachoroid layer consists of compact reticulin and collagenous fibers. It is rich in fibroblasts and melanocytes, whose processes run through the entire choroid. The arteries and veins of the choroid have a double endothelial lining and basal and adventitial layers. Bruch’s membrane is made up of an amorphous substance containing elastic reticulin and collagenous fibers. It is bounded on the inside by a cell membrane of pigmentary epithelium and on the outside by a porous membrane of capillary endothelium.

The choroid of some fishes and mammals, for example, ungulates, has a reflecting layer, or a mirror, that intensifies the light stimulation of the photoreceptors and increases the sensitivity of the eye to light.

REFERENCES

Stebaeva, L. F., and O. V. Volkova. “Ul’trastruktura sosudistoi obo-lochki glaza krolika v norme i pri allergicheskom uveite.” Arkhiv anatomii, gistologii i embriologii, 1974, vol. 66, no. 2.
System of Ophthalmology, vol. 2. Edited by S. Duke-Elder. London, 1961.
Structure of the Eye: Proceedings of the Symposium at the Seventh International Congress of Anatomists. New York-London, 1961.

O. G. STROEVA

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EYLEA has already been approved for the treatment of visual impairment due to myopic choroidal neovascularization in Japan.
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PCV, a disease of the choroidal vasculature, is present in both men and women of many ethnicities, characterized by detachments of the pigmented epithelium and exudative changes that can commonly lead to subretinal fibrosis.
It has been demonstrated that submaximal exercise increases the choroidal blood flow velocity relative to the increase in mean arterial pressure (MAP) (Hayashi et al.
reported a 17-year-old female ALL patient with serous retinal detachment and choroidal hemorrhagic infiltration as the presenting signs of relapse, without concurrent bone marrow or central nervous system involvement 1 year after cessation of therapy.
External beam radiotherapy of choroidal metastases - final results of a prospective study of the German Cancer Society (ARO 95-08).
The incidence of choroidal invasion varies greatly in various reported series, ranging from 15.
Optic nerve and choroidal spread was seen in 15 patients.
Therapeutic manipulation of microRNAs 23 and 27 may give us a way to treat choroidal neovascularization in patients with degenerative retinal diseases.
An international group of contributors working in ophthalmology, genetics, and biological sciences discuss connected diseases like Usher syndrome; early detection; genetic risk factors; therapies used to treat choroidal neovascularization due to age-related macular degeneration; the benefits and risks of cataract surgery for patients with macular degeneration; systemic drugs thought to cause retinal changes; the role of a new class of photoreceptor; retinal flecks; and visual training.
It is believed that the VGAM is the result of an arteriovenous connection between the primitive choroidal arteries and the MPM.
did not state whether these procedures had been performed on their patients to confirm or exclude retinal or choroidal vasculopathy in the macula.