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.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

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.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
* 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.
A cyclodialysis cleft is the result of the separation of the longitudinal ciliary muscle fibers from scleral spur and causes an abnormal drainage pathway for the aqueous humor [1, 2].
With chromium deficiency, less glucose can be drawn from the capillaries to fuel the ciliary muscles. Reduced ciliary muscle response reduces close-work eye focusing ability.
Chromium also aids in enhancing energy to the ciliary muscles necessary for eye focusing, which in turn relieves impetus for excessive eyeball elongation.
Sheppard and Davies [27] reported that the ciliary muscle becomes thicker with age, and they also observed an anterior-interior shift in the ciliary muscle mass.
Davies, "The effect of ageing on in vivo human ciliary muscle morphology and contractility," Investigative Ophthalmology and Visual Science, vol.