A 42-year-old man presented to the emergency room (ER) with headache and neck pain associated with dysgeusia for three days. The headache was described as sudden, moderate, with throbbing pain, located in the left frontal region, and radiating to the left temporomandibular joint. The pain was not aggravated by chewing or position. He denied mechanical trauma to the neck including deep tissue massage or chiropractic manipulation. He had also incidentally noticed that orange juice tasted bitter. He denied a change in voice or difficulty swallowing.
The exam was notable for left-sided ptosis and altered taste to the posterior 1/3rd tongue to sugar water. CT angiography showed irregularity of the distal left internal carotid artery (ICA) from the C1 segment into the proximal petrosal segment associated with a 3 mm pseudo-aneurysm, concerning for dissection.The mean annual incidence of spontaneous ICA dissection is 2.9 per 100,000. The classic triad of symptoms is ipsilateral head or neck pain, partial Horner syndrome, and cerebral or retinal ischemic symptoms. Cranial nerve (CN) palsies may occur in more than 10% of patients with extracranial ICA dissections, most commonly involving CN XII, followed by V, VII, IX and X.
We discuss a patient with isolated dysgeusia in the posterior 1/3rd of the tongue with left-sided Horner syndrome in the setting of distal ICA dissection. Clinical presentation is consistent with an isolated glossopharyngeal nerve palsy and Horner syndrome. At the distal cervical level, the glossopharyngeal nerve and sympathetic tract run closely to the ICA and are susceptible to compression by the pseudoaneurysm. There exist only a few reports on loss of taste sensation caused by dissection of ICA.