Transient opercular syndrome: a manifestation of uncontrolled epileptic activity.

Newly appearing oral motor apraxia should alert physicians to the possibility of an organic lesion in the operculum, the perisylvanian cortex. A 6 1/2-year-old boy who is being followed for complex partial seizures with secondary generalization failed to respond to carbamazepine and then to the addition of sodium valproate. The further addition of lamotrigine stopped the seizures but the patient presented with a new onset of opercular syndrome, manifested by severe oral motor apraxia with difficulties in chewing and swallowing and speech. MRI study of the brain revealed no abnormalities. The opercular syndrome resolved completely when the lamotrigine was replaced with phenobarbital, and did not recur during the follow-up period of 2 years. The EEG, however, continued to be abnormal. We conclude that opercular syndrome may be a manifestation of abnormal localized electrical activity at the operculum, even in the absence of an organic lesion on imaging studies, and it may be a marker for an epilepsy which is not easily controlled.