Epilepsy Semiology for Localization of Epileptogenic Zone

Abstract

Epilepsy is the second most common neurological disorder. Seizure semiology is a simple allows localization of the symptomatogenic zone which either overlaps or is in close proximity of the epileptogenic zone. Clinical semiology can aids to precisely localize the epileptogenic zone is crucial for surgical success essential in cases of possible epilepsy surgery by Video–EEG monitoring. The clinical manifestation of a seizure (seizure semiology) is also of localizing value. For example, a typical patient with TLE may have an epigastric aura, followed by a quiet period of unresponsiveness with staring, lip-smacking (oral automatisms), picking at sheets or clothes (manual automatisms), contralateral dystonic posturing, postictal confusion and lethargy, and postictal nose wiping with the ipsilateral hand. If seizures arise from the dominant hemisphere, there is usually delayed recovery of language, often with transient aphasia and paraphasic errors on language testing. A typical frontal lobe seizure will occur from sleep with no warning, may show restlessness, prominent bilateral limb movements (such as bicycling or asymmetric tonic posturing, or both, and will end quickly with immediate recovery. This may recur several times in one night. Some patients with frontal lobe seizures may present with stereotypical bizarre and violent thrashing behaviors with prominent motor features. Occipital lobe seizures often have a visual aura, and may progress (due to electrical spread) into a temporal lobe or frontal lobe type of seizure. Parietal lobe seizures are the least common, may have a sensory aura, and tend to mimic frontal lobe seizures.