Abstracts

Rationale: Malignant Rolandic-Sylvian epilepsy (MRSE) is characterized by fronto-centro-temporal EEG spikes, normal MRI, medically refractory focal onset seizures and Rolandic-Sylvian spike sources on magnetoencephalography (MEG). Rolandic MEG spike sources are often found in benign epilepsy in childhood with Rolandic spikes (BECRS) and atypical benign partial epilepsy (ABPE). We describe a further series of patients extending the spectrum of MRSE and compare these with atypical benign partial epilepsy (ABPE). Methods: We retrospectively analyzed seizure profiles, scalp video EEG (VEEG), MRI, MEG, and intracranial VEEG of 15 patients: 8 MRSE,7 ABPE. Results: MRSE: 4 girls and 4 boys (age range 2 years-17 years, mean 10.5 years). Seizure onset: 3 months to 3 years (mean 1.4 yrs): multiple seizure types. Motor semiology in 8 (head/eye/face deviation) sensory in 5 and staring in 4. One each had myoclonic seizures, epileptic spasms, aura and secondary generalization. Scalp VEEG showed centro-temporal epileptiform discharges: 8 unilateral and 3 bilateral. Ictal onset and interictal discharges were concordant in 6 (unilateral, 3 left, 3 right). Two with generalized ictal onset had lateralized interictal discharges. Initial MRI was normal in 6 patients, non-specific in 1 and localized in 1. MEG showed clustered spike sources over the post-central gyrus in 2, peri-Rolandic region in 3, pre-central in 1 and frontal in 1. All were medically refractory. Five patients (range 10-17 yrs) had intracranial VEEG and surgical resection. Interval from seizure onset to surgery was 7.5 to 17 years. Ictal onset zone on invasive monitoring was post-central in 3 and pre-central in 2. Two had post-central gyrectomies, one had parietal resection with pre-central multiple sub-pial transaction and 2 had pre-central Rolandic resections. Three were seizure-free and 2 had reduced seizures. Histopathology showed focal cortical dysplasia in 2 and subpial/cortical gliosis in 3. Short-term post-operative face/hand weakness/ataxia with aphasia were seen in 3 and resolved at follow-up. ABPE patients consisted of 3 girls and 4 boys (age range 7 to 12 years, mean 9.6 years). Age range at seizure onset was from 15 months to 4 years (mean 3 years). All 7 patients had multiple types of seizures including atonic seizures once during their seizure history. EEG showed spike or sharp and waves over the bilateral centro-temporal regions. All had normal MRI brain. MEG showed spike sources on bilateral/unilateral frontal operculum region in all. Ethosuximide improved atonic seizures in all. None had surgical intervention. Conclusions: MRSE patients had predominant sensory/motor medically refractory seizures . ABPE patients had multiple seizure types and atonic seizures controlled by Ethosuximide. ABPE localized to the inferior Rolandic and Sylvian region around the frontal operculum whereas MEG spike sources in MRSE localised to the Rolandic region, correlating to seizure semiology. MEG can differentiate MEG spike source localization between MRSE and ABPE and identify the mechanisms of their seizures.