Lack of aura experience correlates with bitemporal dysfunction in mesial temporal lobe epilepsy

The diagnostic value of lack of aura experience in patients with temporal l obe epilepsy (TLE) is unclear. Purpose: To evaluate possible factors of bit emporal dysfunction in patients with mesial TLE who did not experience an a ura in electroencephalography EEG/video monitoring for epilepsy surgery. Me thods: Ictal scalp EEG propagation patterns of 347 seizures of 58 patients with mesial temporal lobe sclerosis or non-lesional mesial TLE, interictal epileptiform discharges (IED), presence of unilateral mesial temporal lobe sclerosis in visual magnetic resonance imaging (MRI) analysis, prose memory performance, history or not of an aura, and postictal memory or absence of an aura were analyzed. The ictal EEG was categorized as follows. EEG seizu re: (a) remaining regionalized, (b) non-lateralized. (c) showing later swit ch of lateralization or bitemporal asynchronous ictal patterns. Results: Ab sent aura in monitoring was significantly correlated with absence of unitem poral MRI sclerosis (P = 0.004). bitemporal IED (P = 0.008), and propagatio n of the ictal EEG to the contralateral temporal lobe (P = 0.001). Other hi storical data and interictal prose memory performance were not significantl y correlated with absent aura. Ten of 11 patients without aura in monitorin g also had absent or rare auras in their history. Conclusions: Lack of aura experience strongly correlates with indicators of bitemporal dysfunction s uch as bitemporal interictal sharp waves and bitemporal ictal propagation i n scalp EEG. and absence of lateralized MRI sclerosis in patients with mesi al TLE. The fact that absent auras are not correlated with episodic memory suggests a transient memory deficit, probably because of rapid propagation to the contralateral mesial temporal lobe. (C) 2001 Elsevier Science B.V. A ll rights reserved.