Facial nerve palsy secondary to internal carotid artery dissection.

We report facial palsy as the sole cranial neuropathy complicating an ipsilateral internal carotid artery dissection. A previously healthy 44-year-old man developed retro-orbital and temporal headache with associated nausea while engaged in modest physical exercise. On the following morning he noticed a left ptosis and miotic pupil. One week later he woke with a left facial weakness. On the same day he had a 90-minute episode of expressive dysphasia. Magnetic resonance imaging and angiography demonstrated left internal carotid artery dissection. The temporal association between our patient's facial nerve palsy and typical features of spontaneous internal carotid artery dissection suggests a common aetiology. We suggest that involvement of the VII cranial nerve in isolation followed disruption of an anomalous nutrient artery. The delay in clinical manifestation may imply extension of the dissection.