title: Modern techniques of epileptic focus localization.
abstract: A clear concept of epileptic zones remains of high clinical relevance in presurgical evaluation of refractory epilepsy patients and in resection planning. Recent advances in understanding how each of the epileptic zones is functionally organized strengthened the importance of the network concept. It has been shown that neuronal networks underlying the individual epileptic zone may involve multiple brain structures with complex interactions between them. The network concept has impact not only for better understanding of pathophysiology of partial epilepsy but also for clinical practice, particularly for epilepsy surgery. This review examines recent reports on the use of advanced imaging techniques which enable to map the epileptic zones and their structural and functional organization. Magnetic resonance postprocessing substantially improved the accuracy in detection of the epileptogenic lesions. The seizure-onset zone is primarily determined by electrophysiology but can also be localized using single photon emission computed tomography. The functional deficit zone is commonly assessed by a number of tests including methods of functional neuroimaging (positron emission tomography) which can delineate hypometabolic cortical areas and subcortical structures. Hemodynamic fluctuations associated with interictal epileptiform discharges can be detected by novel functional magnetic resonance technique which is nowadays widely used for the irritative zone localization. These techniques open new prospect for epilepsy surgery in patients who were previously considered as not suitable candidates of surgical treatment.
authors: Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic.
authors: Lukas
authors: L
authors: Martinkovic
authors: Zagreb Epilepsy Center, Department of Neurology, University Hospital, Zagreb, Croatia.
authors: Hrvoje
authors: H
authors: Hecimovic
authors: Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic.
authors: Vlastimil
authors: V
authors: Sulc
authors: CEITEC-Central European Institute of Technology, Masaryk University, Brno, Czech Republic; Brno Epilepsy Center, Department of Neurology, St. Anne's University Hospital and Faculty of Medicine, Masaryk University, Brno, Czech Republic.
authors: Radek
authors: R
authors: Marecek
authors: Department of Neurology, Charles University in Prague, 2nd Faculty of Medicine, Motol University Hospital, Prague, Czech Republic. Electronic address: petr.marusic@fnmotol.cz.
authors: Petr
authors: P
authors: Marusic
mesh_terms: D001921:Brain / Q000473:pathology* / Q000503:physiopathology*; D004569:Electroencephalography; D004827:Epilepsy / Q000175:diagnosis* / Q000628:therapy; D006801:Humans; D059906:Neuroimaging
keywords: Epilepsy; Epileptic zones; Functional magnetic resonance; Morphometric analysis; Neuroimaging; Positron emission tomography; Single photon emission computed tomography; Volumetrics