Corpus: Ophthalmic artery
1. Definition
The ophthalmic artery is a vascular branch of the internal carotid artery.
2. Course
The ophthalmic artery arises from the internal carotid artery on the medial side of the anterior clinoid process, shortly after the internal carotid artery exits the cavernous sinus. It runs lateral and caudal to the optic nerve, passing through the optic canal into the orbit. The artery then crosses over the optic nerve and continues rostrally along the medial wall of the orbit, accompanying the superior oblique muscle. As it progresses, the ophthalmic artery gives off numerous branches that supply the orbit, lacrimal gland, forehead, ethmoid air cells, dura mater, and parts of the nasal mucosa.
3. Branches
The branches of the ophthalmic artery can be divided into 2 groups. The orbital group supplies the orbit and the surrounding area, the ocular group supplies the eyeball and the eye muscles.
3.1. Orbital branches
- Lacrimal artery
- Supraorbital artery
- Posterior ethmoidal artery
- Anterior ethmoidal artery
- Medial palpebral artery (terminal branch)
- Dorsal nasal artery (terminal branch)
- Supratrochlear artery (terminal branch)
3.2. Ocular branches
4. Anastomoses
The ophthalmic artery forms key anastomoses that help maintain blood supply to the brain and surrounding areas, especially when other pathways are compromised.
One important connection is the meningoorbital artery, formed between the lateral orbital branches and the middle meningeal artery.
Another is the frontal ramus anastomosis, linking the lacrimal and supraorbital arteries with the frontal branch of the superficial temporal artery, which supports collateral blood flow to the brain in cases of internal carotid artery stenosis.
Additionally, the dorsal nasal artery anastomoses with the angular artery, helping to maintain blood supply to the nasal and periorbital regions.
5. Clinic
Ischemia of the ophthalmic artery can lead to a reduced blood supply to the retina, manifesting as visual disturbances and, in severe cases, blindness.