Isolated vagus nerve paralysis associated with internal carotid artery dissection.

Dysphagia and hoarseness caused by laryngopharyngeal paralysis associated with internal carotid artery (ICA) dissection is rare. We reported a case which recovered spontaneously. A 57-year old man visited our hospital complaining of dysphagia and hoarseness lasting for two weeks. Paralysis of right vocal fold and rotational movement of the posterior pharyngeal wall toward the left side during swallowing were observed. Magnetic resonance imaging was performed under diagnosis of isolated right vagus nerve paralysis, and dissection of the right ICA was revealed. He was treated conservatively, and both of laryngopharyngeal movement and the ICA dissection were improved completely. There is a possibility that laryngeal paralysis caused by ICA dissection has been misdiagnosed as an idiopathic paralysis.