Optic strut

The optic strut is a paired bony projection that joins the body of the sphenoid bone with the anterior clinoid process of the lesser wing of the sphenoid bone. It separates the optic canal superomedially from the superior orbital fissure inferolaterally . It also borders the anterior aspect of the clinoid segment of the internal carotid artery .

The optic strut is sometimes pneumatized, allowing endoscopic access from the sphenoid sinus (at the lateral opticocarotid recess) to the anterior clinoid process .

The optic strut is a useful imaging landmark located 2 mm inferior to the distal dural ring, which is used to distinguish intradural versus extradural paraclinoid aneurysms .