Short posterior ciliary arteries
Encyclopedia
The short posterior ciliary arteries from six to twelve in number, arise from the ophthalmic
as it crosses 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 an anastomotic ring, the Circle of Zinn-Haller or Circle of Zinn, which is associated with the fibrous extension of the ocular tendons (Annulus of Zinn
).
Ophthalmic artery
The ophthalmic artery is the first branch of the internal carotid artery distal to the cavernous sinus. Branches of the OA supply all the structures in the orbit as well as some structures in the nose, face and meninges...
as it crosses the optic nerve
Optic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...
.
Course and target
They pass forward around the optic nerveOptic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...
to the posterior part of the eyeball, pierce the sclera
Sclera
The sclera , also known as the white or white of the eye, is the opaque , fibrous, protective, outer layer of the eye containing collagen and elastic fiber. In the development of the embryo, the sclera is derived from the neural crest...
around the entrance of the optic nerve, and supply the choroid
Choroid
The choroid, also known as the choroidea or choroid coat, is the vascular layer of the eye, containing connective tissue, and lying between the retina and the sclera. The human choroid is thickest at the far extreme rear of the eye , while in the outlying areas it narrows to 0.1 mm...
(up to the equator of the eye) and ciliary processes.
Some branches of the short posterior ciliary arteries also supply the optic disc
Optic disc
The optic disc or optic nerve head is the location where ganglion cell axons exit the eye to form the optic nerve. There are no light sensitive rods or cones to respond to a light stimulus at this point. This causes a break in the visual field called "the blind spot" or the "physiological blind spot"...
via an anastomotic ring, the Circle of Zinn-Haller or Circle of Zinn, which is associated with the fibrous extension of the ocular tendons (Annulus of Zinn
Annulus of Zinn
The annulus of Zinn, also known as the annular tendon or common tendinous ring, is a ring of fibrous tissue surrounding the optic nerve at its entrance at the apex of the orbit. It is the origin for five of the six extraocular muscles...
).