Clinical manifestations of carotid dissection

Spontaneous dissection of the cervical internal carotid artery (sICAD) causes, in more than 90% of patients, carotid territory ischemia, local signs and symptoms on the side of dissection, or both, whereas the remaining sICAD remain clinically asymptomatic. Local signs and symptoms include head, facial, or neck pain, Horner syndrome, pulsatile tinnitus, and cranial nerve palsy. Head, facial, or neck pain occurs in 64-74% and is the presenting symptom in up to 58.5%, and the only manifestation in 2.2-4.5%. Headache is observed in 65-68%, facial pain in 34-53%, and neck pain in 9-26%. Horner syndrome consisting essentially of miosis and ptosis is detected in 28-41%. Cranial nerve palsy is reported in 8-16%; the lower cranial nerves IX-XII are most commonly affected, in particular the hypoglossal nerve. The facial nerve may also be involved; dysgeusia results mainly from involvement of the chorda tympani (0.5-7.0%) or the glossopharyngeal nerve. Transient pareses of the ocular motor (III, IV and VI) and trigeminal nerves have been observed. Pulsatile tinnitus is reported in 16-27%. About three quarters of sICAD cause ischemic events, which include ischemic stroke in 80-84%, transient ischemic attack in 15-16%, amaurosis fugax in 3%, ischemic optic neuropathy in 4%, and retinal infarct in 1%. Patients with sICAD causing ischemia show a lower prevalence of Horner syndrome and palsy of the caudal cranial nerves than patients with sICAD causing no ischemic events, whereas headache, neck pain, and pulsatile tinnitus are equally frequent in both groups. After an ischemic stroke, independency defined by a moderate Rankin scale score of 0-2 occurs in 63-90%, whereas the outcome of retinal infarct and ischemic optic neuropathy are not well known.