Carotid artery dissection Internal carotid artery dissection 2013-02-16T07:22:28Z A separation (dissection) of the layers of the internal carotid artery wall. The internal carotid begins at the bifurcation of the common carotid, opposite the upper border of the thyroid cartilage, and runs perpendicularly upward. It supplies the anterior part of the brain, the eye and its appendages, and sends branches to the forehead and nose. Interstitial hemorrhage into the media of the vessel wall can lead to occlusion of the internal carotid artery and aneurysm formation. HP:0012159 SNOMEDCT_US:705066004 UMLS:C0751815