Ocular motor nerve palsies in spontaneous dissections of the cervical internal carotid artery

Cranial nerve palsies affecting ocular motor function in patients with spontaneous cervical internal carotid artery dissections are rare. Among 155 patients with spontaneous dissections of the cervical internal carotid artery, four (2.6%) had transient third, fourth, or sixth cranial nerve palsy. The third nerve was involved in two patients, the fourth nerve in one, and the sixth nerve in one. Three patients had ipsilateral headache or facial pain, one had bilateral headaches, and three had oculosympathetic palsy. None had any associated cerebral or retinal ischemic symptoms. Cervical internal carotid artery dissection should be included in the differential diagnosis of palsies of the third, fourth, or sixth cranial nerve, especially when associated with ipsilateral headache or facial pain. Interruption of the nutrient arteries supplying these cranial nerves could explain their involvement by internal carotid artery dissection.