MR neurography of a vagal neuropathy

A 46-year-old man with a history of recurrent facial nerve palsies, right trigeminal neuralgia, and Horner syndrome presented with subacute onset of right laryngeal hemiparesis. CSF analysis revealed normal cell count and elevated protein level with albumin-cytologic dissociation.1 Imaging workup ruled out compressive and infiltrative causes. Magnetic resonance neurography (figures 1A and 2, A–D) demonstrated uniform thickening, T2 signal hyperintensity, and contrast enhancement of the right vagal nerve, from skull base to the thyroid level. The right true vocal cord appeared adducted, T2 hyperintense, with contrast enhancement (figures 1B and 2, C–D), suggesting acute muscle denervation.2 A diagnosis of chronic inflammatory demyelinating cranial neuropathy was considered.