Vernet's syndrome after carotid endarterectomy

Unilateral paresis of cranial nerves IX to XI is defined as Vernet's syndrome. We retrospectively assessed cranial nerve symptoms from the clinical records of 143 carotid endarterectomy patients. A flexible nasolaryngoscope was used to examine vocal fold movements in 73 patients. If vocal fold paresis (VFP) was confirmed, the patient also underwent magnifying laryngoscopy (for correct diagnosis of injury to the glossopharyngeal and vagus nerves). It was found from clinical records that 8 patients (6%) were confirmed to have cranial nerve symptoms corresponding to Vernet's syndrome; 7 patients (9 %) had VFP on nasolaryngoscopy. In 2 patients, magnifying laryngoscopy confirmed ipsilateral VFP, pharyngeal paresis, pharyngeal wall hypesthesia, and ipsilateral pharyngeal wall swelling. These 2 patients also had symptoms of injury to the accessory nerve. Damage to cranial nerves IX to XI probably occurred in the parapharyngeal space, based on the existence of posterior pharyngeal wall edema or swelling after carotid endarterectomy.