Acquired epileptiform opercular syndrome: a case report and results of single photon emission computed tomography and computer-assisted electroencephalographic analysis

We report here a girl aged 5 years 3 months with cryptogenic localization-r elated epilepsy who showed a prolonged episode characterized by dysarthria, dysphagia, drooling and paresis of the right arm associated with almost co ntinuous diffuse sharp-slow wave complexes during sleep. These symptoms wer e not directly related to seizures or to each sharp-slow wave complex revea led by examination during the video electroencephalographic (EEG) recording . The interictal single photon emission compute tomography showed a localiz ed high perfusion area in the left posterior frontal region. The introducti on of clonazepam completely controlled the clinical symptoms as well as the EEG abnormality within 2 weeks. After 4 months of remission, a similar epi sode recurred which was associated with aggravation of EEG. The clinical an d EEG characteristics of this patient were identical to those of acquired e pileptiform opercular syndrome (AEOS), a newly proposed epileptic syndrome, in which a transient operculum syndrome develops in association with conti nuous spike-and-wave activity during slow sleep (CSWS). Computer-assisted E EG analysis demonstrated that the epileptic EEG focus was located in the le ft sylvian fissure, and produced secondary bilateral synchronous sharp-slow complexes. The present study further supports the hypothesis that the elec trical interference by CSWS creates bilateral opercular dysfunction through the mechanism of secondary bilateral synchrony, thus producing AEOS. (C) 2 001 Elsevier Science B.V. All rights reserved.