Posterior ethmoidal artery

The posterior ethmoidal artery is an artery of the head which supplies the nasal septum. It is smaller than the anterior ethmoidal artery.
Course.
Once branching from the ophthalmic artery, it passes between the upper border of the medial rectus muscle and superior oblique muscle to enter the posterior ethmoidal canal. It exits into the nasal cavity to supply posterior ethmoidal cells and nasal septum; here it anastomoses with the sphenopalatine artery.
There is often a meningeal branch to the dura mater, while it is still contained within the cranium.
Supplies.
This artery supplies the posterior ethmoidal air sinuses, the dura mater of the anterior cranial fossa, and the upper part of the nasal mucosa of the nasal septum.