Teaching NeuroImages: internal carotid artery dissection presenting as Villaret syndrome.

A 63-year-old man presented with headache, hoarseness, and dysphagia. He had a left-sided Horner syndrome and wasting of the left sternocleidomastoid muscle. His tongue was deviated to the left on protrusion (figure 1). MRI and CT angiography revealed a distal left internal carotid artery dissection (figure 2). Villaret syndrome is a rare clinical entity comprising IX, X, XI, and XII cranial nerve palsies together with Horner sign. This constellation of signs should prompt the clinician to seek pathology in the retroparotid space, as this is the only area where the lower 4 cranial nerves and sympathetic fibers to the eye lie in close proximity. When the sympathetic fibers are spared, it is termed Collet-Sicard syndrome. Figure 1 Cranial nerve palsies in Villaret syndrome