Anterior ethmoidal artery

At a glance

English

Anterior ethmoidal artery

Latin (TA2)

Arteria ethmoidea anterior

System

Artery

Region

Head

Side

Paired, left and right

About the anterior ethmoidal artery

The anterior ethmoidal artery arises inside the orbit from the ophthalmic artery, after the posterior ethmoidal artery, as the ophthalmic artery runs forwards along the medial wall. With the anterior ethmoidal nerve it enters the anterior ethmoidal foramen at the suture between the frontal bone and the orbital plate of the ethmoid, and passes medially through the anterior ethmoidal canal.

Its route is unusual because it passes through three spaces. In the canal it gives small branches to the anterior and middle ethmoidal air cells and to the frontal sinus. It then enters the anterior cranial fossa, running on the cribriform plate under the dura, where it gives a meningeal branch to the dura of the front of the fossa, sometimes called the anterior falcine artery. Finally its nasal branches drop through the cribriform plate into the nasal cavity.

In the nose these nasal branches divide. Lateral nasal branches go to the forward part of the side wall of the nose, and medial nasal branches supply the front of the septum. A terminal external nasal branch grooves the inner face of the nasal bone, then emerges below its lower edge, above the lateral nasal cartilage, to reach the skin of the lower dorsum and the tip.

The artery is clinically important in two ways. It contributes to the vascular plexus at the front of the septum, so it can be a source of nosebleed that does not settle with ordinary measures and may need ligation in the orbit. In endoscopic sinus surgery it is a key landmark at the roof of the ethmoid, and injury to it can bleed into the orbit.

Course and supply

Arises from

The ophthalmic artery within the orbit, beyond the origin of the posterior ethmoidal artery.

Ends in

Ends in nasal branches to the lateral wall and septum of the nose and an external nasal branch to the skin of the nose.

Supplies

Supplies the anterior and middle ethmoidal cells, the frontal sinus, the dura of the anterior cranial fossa, the forward nasal cavity and the nasal skin.