The spectrum of hypermotor seizures: A pragmatic approach

Abstract

Hypermotor seizures (HMS) are characterized by complex movements involving the proximal segments of the limbs and trunk. Seizures frequently begin in childhood, with a nocturnal predominance, and possible drug-resistance leading to epilepsy surgery. HMS are usually considered to arise from the frontal lobe but they can also arise from other cerebral regions. Whether there exist anatomo-electro-clinical features that allow to distinguish HMS of frontal origin from extra-frontal origin remains a crucial issue in epilepsy surgery candidates. General features and anatomo-electro-clinical findings were retrospectively reviewed in a cohort of 28 HMS patients who underwent surgery or radio-frequency thermo-coagulations in our center. Based on surgery location and SEEG data, patients were divided in 2 groups: a 'pure' frontal lobe epilepsy (FLE) group (n=14) and an extra-FLE group (n=14). The 2 groups of patients were difficult to distinguish based on general features, MRI findings and interictal scalp-EEG abnormalities. Ictal scalp EEG more frequently show an anterior frontal onset in the FLE group (p=0.01), whereas it was more frequently non-localizing in extra-FLE patients (p=0.016). Patients with extra-FLE presented more frequently a marked agitation (p=0.046) and screaming (p=0.006). Patients with FLE had more frequently a short seizure duration (<30s) (p=0.033). Our data indicate that both ictal scalp-EEG data and a detailed analysis of ictal clinical signs of HMS may help to differentiate HMS of frontal lobe origin from HMS arising from extra-frontal lobe regions among patients contemplating epilepsy surgery.