Medial wall of orbit

Medial wall of orbit on both sides run parallel to each other. These walls also serve as the lateral walls of the nasal cavity.

To form the medial wall of orbit, the sphenoid bone, orbital surface of the ethmoid bone, lacrimal bone, and frontal process of the maxilla come together.

• The ethmoid bone contains air-filled spaces called ethmoidal air cells in the medial wall.

• Located at the junction of the roof and the ethmoidal part of the medial wall of orbit, you can find the anterior and posterior ethmoidal foramina. These foramina allow the passage of anterior and posterior ethmoidal nerves and vessels, which are branches of nasociliary nerve and exit the orbit through these openings to enter the anterior cranial fossa above.

• Towards the back, the junction of medial wall and roof, lies the optic canal. This canal provides passage for the optic nerve and ophthalmic artery.

• In the front, there is a lacrimal groove that holds the lacrimal sac. The margins of this groove are known as the anterior and posterior lacrimal crests. These crests are formed by the maxilla and lacrimal bones, respectively. The lacrimal fascia covers the groove as well as the lacrimal gland. Below, the groove leads into the nasal cavity (inferior meatus) through the nasolacrimal duct, also referred to as the tear duct.