Ciliary arteries

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Artery: Ciliary arteries

The ophthalmic artery and its branches. (Ciliary artery visible near center.)

The arteries of the choroid and iris. The greater part of the sclera has been removed.
Latin	aa. ciliares
Gray's	subject #146 571

The Ciliary Arteries are divisible into three groups, the long posterior, short posterior, and the anterior.

The short posterior ciliary arteries from six to twelve in number, arise from the ophthalmic as it crosses the optic nerve; they pass forward around the optic nerve to the posterior part of the eyeball, pierce the sclera around the entrance of the optic nerve, and supply the choroid (up to the equator of the eye) and ciliary processes. Some branches of the short posterior ciliary arteries also supply the optic disc via a anastomotic ring (Circle of Zinn).

The long posterior ciliary arteries, two in number, pierce the posterior part of the sclera at some little distance from the optic nerve, and run forward, along either side of the eyeball, between the sclera and choroid, to the ciliary muscle, where they divide into two branches; these form an arterial circle, the circulus arteriosus major, around the circumference of the iris, from which numerous converging branches run, in the substance of the iris, to its pupillary margin, where they form a second arterial circle, the circulus arteriosus minor. The long posterior ciliary arteries supply the iris, ciliary body and choroid.

The anterior ciliary arteries are derived from the muscular branches of the Ophthalmic Artery; they run to the front of the eyeball in company with the extraocular muscles, form a vascular zone beneath the conjunctiva, and then pierce the sclera a short distance from the cornea and end in the circulus arteriosus major. These arteries supply the conjunctiva & sclera.

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.