Correlation between temporal pole MRI abnormalities and surface ictal EEG patterns in patients with unilateral mesial temporal lobe epilepsy

Objective: the objective of this retrospective study is to analyze ictal patterns observed during continuous Video-EEG monitoring in patients with temporal Lobe epilepsy (TLE) due to unilateral hippocampal sclerosis (HS), and to correlate these EEG patterns to temporal pole abnormalities observed on...

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Detalhes bibliográficos
Autores: Caboclo, Luís Otávio Sales Ferreira [UNIFESP], Garzon, Eliana [UNIFESP], Oliveira, Pedro A. L., Carrete Junior, Henrique [UNIFESP], Centeno, Ricardo Silva [UNIFESP], Bianchin, Marino Muxfeldt, Yacubian, Elza Márcia Targas [UNIFESP], Sakamoto, Américo Ceiki [UNIFESP]
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Brasil
Recursos:Universidade Federal de São Paulo (UNIFESP)
Repositorio:Repositório Institucional da UNIFESP
Idioma:inglés
OAI Identifier:oai:repositorio.unifesp.br:11600/29333
Acesso em linha:http://dx.doi.org/10.1016/j.seizure.2006.09.001
http://repositorio.unifesp.br/handle/11600/29333
Access Level:acceso abierto
Palavra-chave:temporal lobe epilepsy
hippocampal sclerosis
Video-EEG
EEG patterns
temporal pole
epilepsy surgery
Descrição
Resumo:Objective: the objective of this retrospective study is to analyze ictal patterns observed during continuous Video-EEG monitoring in patients with temporal Lobe epilepsy (TLE) due to unilateral hippocampal sclerosis (HS), and to correlate these EEG patterns to temporal pole abnormalities observed on magnetic resonance imaging exams.Methods: We analyzed 147 seizures from 35 patients with TLE and unilateral HS. Ictal patterns were classified.,and correlated to signal abnormalities and volumetric measures of the temporal poles. Volume differences over 10% were considered abnormal.Results: the most frequent type of ictal pattern was rhythmic theta activity (RTA), encountered in 65.5% of the seizures. Rhythmic beta activity (RBA) was observed in 11% of the seizures, localized attenuation in 8%, interruption of epileptiform discharges in 6%, repetitive discharges in 5.5%, and rhythmic delta activity (RDA) in 4%. Sixty-six percent of the patients presented signal abnormalities in the temporal pole that were always ipsitateral to the HS. Sixty percent presented significant asymmetry of the temporal poles consisting of reduced volume that was also always ipsitateral to HS. Although patients with RTA as the predominant ictal pattern tended to present asymmetry of temporal poles (p = 0.305), the ictal EEG pattern did not correlate with temporal pole asymmetry or signal abnormalities.Conclusions: RTA is the most frequent initial ictal pattern inpatients with TLE due to unilateral HS. Temporal pole signal changes and volumetric reduction were commonly found in this group of patients, both abnormalities appearing always ipsitateral to the HS. However, neither temporal pole volume reduction nor signal abnormalities correlated with the predominant ictal pattern, suggesting that the temporal poles are not crucially involved in the process of epileptogenesis. (c) 2006 British Epilepsy Association. Published by Elsevier B.V. All rights reserved.