Investigation of focal epilepsies using quantitative analysis of the video-electroencephalogram and neuroimaging

Abstract

Focal epilepsies are heterogeneous, serious and frequent pathologies. The major challenge in the evaluation of patients with refractory focal epilepsies is the identification of the ictal onset zone and, therefore to identify the etiology of the epileptic seizures. To perform this diagnosis clinical evaluation, video-electroencephalography (VEEG) and neuroimaging are essential. The clinical evaluation is important because details from the clinical history and neurological examination may help in the diagnostic suspicion of focal epilepsies. VEEG allows the documentation of the clinical-electroencephalographic features of the epileptic seizures supporting the findings of the clinical history. Neuroimaging, mainly magnetic resonance imaging (MRI), is the best form of structural evaluation of the brain and is an important tool for the etiological diagnosis of the seizures. The analysis of the VEEG and MRI may be qualitative or quantitative. Qualitative analysis of the exams is the conventional visual assessment. Quantitative analysis consists in the application of mathematical algorithms by computer softwares in order to increase the sensibility of a diagnostic procedure. Forty patients with focal refractory epilepsy will be selected according to the clinical history from the Ambulatório de Epilepsia do Hospital das Clínicas da Faculdade de Medicina de Botucatu. All of them will be submitted to VEEG and MRI. The current project has as a general objective to improve the investigation of the epilepsies with the creation of the Unidade de Investigação das Epilepsias which will group the Serviço de Neurofisiologia and the Laboratório de Pesquisa em Neuroimagem. Qualitative and quantitative techniques will be used for the evaluation of the VEEG and MRI with the following specific objectives: localization of the ictal onset zone, identification of the seizures etiology and to map the neural network involved in the physiopathology of the focal epilepsies. (AU)