Ciliary Body


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ciliary body

[¦sil·ē‚er·ē ¦bäd·ē]
(anatomy)
A ring of tissue lying just anterior to the retinal margin of the eye.

Ciliary Body

 

in terrestrial vertebrates, including humans, the part of the eye that converts blood serum into the intraocular fluid that is secreted into the posterior chamber of the eye. The ciliary body forms a circle of numerous radial folds (70 to 80 in humans) on the internal surface of the eye between the iris and the retina. It consists of mesodermal stroma and two neuroepithelia. The external pigmented neuroepithelium is a continuation of the pigmented epithelium of the retina, whereas the nonpigmented internal layer, which plays a major role in the secretion of intraocular fluid, is a continuation of the retina proper.

Fibers of the zonule of Zinn are attached to the basal membrane of the ciliary folds. The amount of tension of the ligament is determined by contraction of the circular ciliary muscle situated in the stroma of the ciliary body near the place of contact with the sclera. The tension of the ciliary muscle determines the shape of the crystalline lens. The ciliary body is the most vascularized part of the eye; it is supplied by blood vessels from the systemic circulation of the iris.

Inflammation of the ciliary body is called cyclitis; inflammation of both the ciliary body and the iris is called iridocyclitis.

REFERENCES

Stroeva, O. G. Morfogenez i vrozhdennye anomalii glaza mlekopitaiushchikh. Moscow, 1971.
Davson, H. The Physiology of the Eye, 3rd ed. Edinburgh-London, 1972.

O. G. STROEVA

References in periodicals archive ?
Bernstein, "The ciliary body is the muscle involved in accommodation, and research in my lab-oratory has shown that it is a carotenoid-rich tissue.
5,19,20) The pigmented epithelium of the ciliary body can also give rise to adenoma and adenocarcinoma (Table).
There were significant associations related to ciliary body involvement, the presence of epithelioid cell type, the TNM stages, and the presence of metastasis (Table 1).
The iris and ciliary body are located anteriorly to the ora serrata, the site that marks the beginning of the retina.
The ciliary body band is located between the scleral spur and the iris insertion.
2%) of 142 eyes, and included infiltration of iris in 10 eyes (7%), ciliary body invasion in 13 (9%), anterior chamber angle seeds in 13 (9%), choroidal infiltration in 57 (40%), prelaminar optic nerve invasion in 24 (17%), optic nerve lamina cribrosa invasion in 15 (11%), retrolaminar optic nerve extension in 24 (17%), involvement of optic nerve to line of transection in 11 (8%), infiltration of sclera in 13 (9%), and extrascleral extension in 9 (6%) eyes.
Anterior uveitis refers to inflammation of the iris alone (iritis) or the iris and ciliary body.
b) Friction between the anterior iris surface and ciliary body causes sloughing of iris pigment epithelial cells
Islands of tumor and individual tumor cells were present in the space between the vitreous base and ciliary body (Figure 4, B).
Uveitis is an inflammation inside the eye, specifically affecting one or more of the three parts of the eye that make up the uvea: the iris (the colored part of the eye), the ciliary body (behind the iris, responsible for manufacturing the fluid inside the eye) and the choroid (the vascular lining tissue underneath the retina).
The patient is often asymptomatic although a ciliary body mass can cause lens tilting or anterior displacement of the lens, which results in an uncorrectable astigmatism.
Traditionally, several features, such as large size, epithelioid cell type, presence of positive periodic acid-Schiff (PAS) vascular mimicry patterns (or extracellular matrix patterns), and ciliary body involvement have been noted to correlate with poor prognosis.