Semiology of temporal lobe epilepsies

Abstract

Temporal lobe epilepsies (TLE) represent the majority of the partial symptomatic/cryptogenic epilepsies. Excellent results of epilepsy surgery in well-selected patients have encouraged a search for localizing and lateralizing signs that could assist in the identification of the best surgical candidates. Seizure types in TLE include simple partial, complex partial and secondarily generalized seizures. Temporal lobe seizures most often arise in the amygdalo-hippocampal region. More than 90% of patients with mesial TLE report an aura, most commonly an epigastric sensation that often has a rising character. Other autonomic symptoms, psychic symptoms, and certain sensory phenomena (such as olfactory) also occur. The complex partial seizures of mesial TLE often involve motor arrest, oroalimentary automatisms or non-specific extremity automatisms at onset. Ictal manifestations that have lateralizing value include dystonic posturing (contralateral), early head turning (usually ipsilateral), and adversive head turning in transition to generalization (contralateral). Well-formed ictal language favors right temporal localization. Ictal vomiting, spitting, and drinking tend to be right sided. The duration of TLE complex partial seizures is generally greater than one minute and postictal confusion usually occurs. When postictal aphasia is noted a left-sided lateralization is favored. A lateral temporal onset is less common in TLE, and is most often suggested by an auditory aura. Somatosensory and visual auras are highly unlikely with TLE, and suggest neocortical extratemporal localization. A cephalic aura is non-specific, but is more common in frontal lobe epilepsy.