Abstracts

RATIONALE:Approximately 20% of patients with epilepsy remain refractory to AED treatment. Definitive localization of an epileptic focus correlates with a favorable outcome following epilepsy surgery, and the efficacy of conventional surgery for epilepsy has been well documented. Scalp EEG localization may be suboptimal due to EMG artifact produced by ictal contraction of cranial muscles. Botox? administration of fronto-temporal scalp muscles significantly reduces EMG artifact and may improve focus localization. METHODS:Scalp videoEEG monitoring in three patients suggested partial seizures, but without definitive lateralization or localization thought to be secondary to EMG artifact. Neuroimaging and neuropychological testing did not assist in further localization. EMG-guided Botox? injection to bilateral fronto-temporal muscles was performed. Three to seven days later, patients underwent EMG artifact assessment with various facial muscle contraction tasks during baseline EEG including attempted elevation of eyebrows, eye opening/closure, squinting, forehead wrinkling, and random mouth/jaw movements. When significant EMG persisted, EMG-guided Botox? administration was selectively repeated. Patients subsequently underwent repeated scalp videoEEG monitoring one week later. RESULTS:All patients had reduction of EMG artifact during subsequent scalp videoEEG monitoring. No patients had significant adverse effects following Botox? administration. All three patients had localization to either frontal or temporal lobes and definitive lateralization. Two of the three patients have undergone invasive placement of fronto-temporal subdural grid electrodes based on the Botox? scalp videoEEG localization. No patients had complications, and all patients recovered muscle strength of fronto-temporal muscles. CONCLUSIONS:Paralysis of scalp muscle following Botox? administration to fronto-temporal muscles reduces EMG artifact and may improve localization and lateralization of a seizure focus.