The anterior clinoid process is a pyramid-shaped bony projection of the lesser wing of the sphenoid bone and forms part of the lateral wall of the optic canal.

[1][3] The anterior clinoid process projects over the internal carotid artery, which supplies the majority of blood to the brain.

[4] Additionally, when an aneurysm forms below the ACP, the projection may create a flat or pointed area of compression that may rupture the vessel.

[5] More frequently, this positioning means that the ACP is an important surgical access point for correction of aneurysms, tumors, and other operations in the structures adjacent to it.

[6] Endovascular surgery has become an increasingly common procedure for lesions and aneurysms around the ACP, as the complex anatomy makes it difficult and dangerous to access via other surgical methods.