Fig. 12

Glossopharyngeal nerve dysfunction. Low cranial nerves palsy. a Coronal fast spin-echo T1-weighted MRI of the neck. A slightly hypointense mass eroding the right jugular foramen (arrow) was demonstrated to be a glomus jugulare paraganglioma. b Coronal fast spin-echo T1-weighted MRI of the neck. The normal stylopharyngeus muscle (arrowhead) on the left and its relationship with the external carotid artery (eca) help to recognise the muscle atrophy on the right side. Stylopharyngeus muscle atrophy is one of the few specific imaging signs of glossopharyngeal nerve dysfunction. c Axial fast spin-echo T1-weighted MRI of the neck. An asymmetric oropharyngeal lumen due to a descending soft palate on the right (arrow) and constrictor muscle atrophy (the arrowhead points to the normal muscles on the left). These are signs of vagus nerve dysfunction, which is normally associated with glossopharyngeal nerve changes. d Axial fast spin-echo T1-weighted MRI of the neck. The uvula (arrow) is displaced to the left side (the dotted midline has been drawn to emphasise that displacement), which is the other typical sign of vagus nerve palsy. Intriguingly, this patient also showed a right parotid gland (pg) atrophy, which might be related to the glossopharyngeal nerve dysfunction. Also note the fat replacement of the right side of the tongue due to hypoglossal nerve palsy