Ciliary Body

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Related to Ciliary muscles: retina, musculus ciliaris

ciliary body

[¦sil·ē‚er·ē ¦bäd·ē]
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.


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


References in periodicals archive ?
In the future, developing new techniques of measuring ciliary muscle ring diameter might help in providing a "customized" IOL fit for treatment to correct presbyopia.
With chromium deficiency, less glucose can be drawn from the capillaries to fuel the ciliary muscles.
Chromium also aids in enhancing energy to the ciliary muscles necessary for eye focusing, which in turn relieves impetus for excessive eyeball elongation.
As discussed above, astaxanthin may reduce eyestrain by improving blood flow to the ciliary muscles.
The mechanisms of action of astaxanthin in reducing eyestrain may include improved blood flow to the ciliary muscles controlling accommodation, as well as anti-inflammatory and antioxidant effects.
When the ciliary muscle within the ciliary body relaxes, it flattens the lens, allowing us a broader, more panoramic view.