Twenty Years of Ictal EEG–EMG


Address correspondence and reprint requests to I. W. Mothersill at Swiss Epilepsy Centre, Bleulerstr. 60, CH-8008 Zürich, Switzerland.


Summary: This study aimed to evaluate the use of ictal EEG recordings combined with simultaneous surface EMG in the diagnosis and analysis of motor events, both epileptic and non-epileptic. All ictal registrations were performed utilizing radio/cable telemetry. Routine recordings consisted of 18-channel EEG plus 8-channels bipolar surface EMG in freely moving patients. Combined ictal EEG—EMG recordings in freely moving patients enabled us to identify and define the following pathomechanisms of epileptic drop seizures, epileptic axial spasms, atonic, myoclonic-atonic, and akinetic seizures. Precise differentiation could be made between tonic and nontonic postural seizures and between startle-induced reflex seizures and hyperekplexia. The findings from telemetered ictal recordings in freely moving patients with combined EEG and surface EMG offer the only means of identifying, defining, and differentiating motor events, both epileptic and nonepileptic, of a short duration that cannot be properly differentiated by clinical examination alone.