Acortico-subcortical suprabulbar or pseudobulbar palsy of the lower cranial nerves, with characteristics of severe dysarthria and dysphagia associated with bilateral central facio-pharyngo-glosso-masticatory paralysis, with prominent automatic-voluntary dissociation in which involuntary movements of the affected muscles are preserved. Less than 150 cases have been described in the literature so far. Can occur at any age. Patients have severe speech disturbances and most are mute.Chewing and swallowing are severely impaired. Caused by developmental or acquired bilateral lesions of the anterior opercula. In children, it presents congenitally (bilateral opercular polymicrogyria) or as an acquired disorder due to encephalitis, epilepsy and neurodegenerative disorders. The syndrome is generally sporadic but some familial cases have been described. [from
SNOMEDCT_US]