Ophthalmic artery

At a glance

English

Ophthalmic artery

Latin (TA2)

Arteria ophthalmica

System

Artery

Region

Head

Side

Paired, left and right

About the ophthalmic artery

The ophthalmic artery supplies everything in the orbit and also parts of the nose, forehead, scalp and meninges. It normally springs from the internal carotid just after that artery leaves the roof of the cavernous sinus, just medial to the anterior clinoid process, though sometimes it arises a little earlier, still within the sinus. It runs forwards through the optic canal below and lateral to the optic nerve, within its dural sheath, though occasionally it lies above the nerve.

Inside the orbit it first lies lateral to the nerve, then, in the back third of the cone of muscles, turns sharply medially, usually crossing above the nerve, to reach the medial wall. It then runs forward beneath superior oblique and ends near the medial end of the upper lid by dividing into the supratrochlear and dorsal nasal arteries, which leave the orbit to supply the forehead and the side of the nose.

Its many branches fall into two groups. The ocular group serves the eyeball and its muscles. The central retinal artery, small and usually first, runs under the optic nerve and pierces it about a centimetre behind the globe to reach the inner layers of the retina. One to five posterior ciliary arteries pierce the sclera near the optic disc as long and short ciliary arteries to supply the choroid; they are end arteries, so blocking one gives a patch of choroidal infarction. Muscular branches, superior and inferior, feed the extraocular muscles and give anterior ciliary arteries. The orbital group serves the rest: the lacrimal artery along lateral rectus to the lacrimal gland, lids and conjunctiva; the supraorbital artery through the supraorbital foramen to the forehead; the posterior and anterior ethmoidal arteries to the ethmoidal cells, nose and dura of the anterior fossa; the medial palpebral arteries to the lids; and the two terminal branches.

Severe narrowing or blockage causes the ocular ischaemic syndrome, with worse sight than a central retinal artery occlusion and usually without its cherry-red spot. A brief drop in pressure in the artery, as in standing up quickly, can cause transient monocular loss of vision, amaurosis fugax. Because its terminal branches join facial and maxillary vessels, total occlusion can sometimes be tolerated.

Course and supply

Arises from

The internal carotid artery, as it emerges from the cavernous sinus, medial to the anterior clinoid process.

Ends in

Ends at the medial side of the orbit by dividing into the supratrochlear and dorsal nasal arteries.

Supplies

Supplies the eyeball, retina, extraocular muscles, lacrimal gland and lids, and also the ethmoidal sinuses, upper nasal cavity, forehead, part of the outer nose and the dura of the anterior cranial fossa.