Localization of the epileptogenic foci in tuberous. Department of neurology and neurosurgery, montreal neurological institute, mcgill university, montreal, quebec, canada. Abstract the definition of the epileptogenic zone, as proposed by talairach and bancaud, is an ictal electroclinical definition based on the results of. Epileptogenic zone definition of epileptogenic zone by. This demands the unambiguous demonstration of the epileptogenicity of one of the tubers. Diagnostic techniques to detect the epileptogenic zone. A the epileptogenic zone ez is the ccurate and safe identification of taylor j.
For a class of focal epileptic patients having drugresistant epilepsy, resective surgery seems to be a valid option for treatment. Specifically, some of the electrographic patterns the epileptologists used. However, visual analysis of seeg still prevails in clinical practice. Fast oscillations associated with interictal spikes localize the epileptogenic zone in patients with partial epilepsy. I state this upfront because over the past several decades, the concept of the epileptogenic zone ez has become so crucial to the foundation of major schools. Epileptogenic zone 71 cortical localization 72 functional neuroimaging 73 pet in epilepsy 74 spect in epilepsy 75 volumetric mri use in epilepsy 76 generalized seizures 77 partial seizures 302 vagus nerve stimulation 78 neonatal seizures 297. Effective brain connectivity computational methods for the. Frontiers localization of epileptogenic zone with the. This is a pdf file of an unedited manuscript that has been accepted for publication. Using network analysis to localize the epileptogenic zone.
We aim to improve epileptogenic zone localization by utilizing a computerassisted tool for the automated grading of the seizure activity recorded in various locations for 20 patients undergoing stereo electroencephalography. Significance meg is a valuable tool for noninvasive interictal spike mapping in epilepsy surgery, including patients with nonlocalized findings receiving longterm eeg monitoring, and localization of the epileptogenic zone using meg is associated with improved seizure outcomes. Precise localization of epileptogenic zones is essential for the successful surgical treatment of refractory epilepsy including lennoxgastaut syndrome lgs. Seizure semiology is a simple and cost effective tool that allows localization of the symptomatogenic zone which either overlaps or is in close proximity of the epileptogenic zone. Ris procite, reference manager citation file or direct import. Rearrange individual pages or entire files in the desired order. The bancaud and talairach view on the epileptogenic zone.
Electrode implantation is guided by hypotheses about localization of the epileptogenic zones that are based on. Automated longterm eeg analysis to localize the epileptogenic zone. The tools available for localization of the epileptogenic zone are limited. Patients with epilepsy often, although not always 3, 8, show increased focal slow delta activity compared to controls, which has been. Objective to test whether diffusionweighted magnetic resonance imaging enables differentiation of epileptogenic tubers from inert ones. In 5 of the cases presenting clearly defined mri lesions with compatible semiology and scalp eeg, the surgeon proceeded directly to resection of the potentially epileptogenic zone. We analyzed the data of the patients with epileptogenic tumor in temporal lobe,in order to highlight the characteristics of these tumors thereby enhancing our clinical and imaging awareness. Three trials found no difference in seizure outcomes. Background patients with tuberous sclerosis complex and drugresistant epilepsy may be considered candidates for epilepsy surgery.
Stereoelectroencephalography seeg, the clinical use of which in the presurgical evaluation of epileptic patients was introduced in the last century by a group at sainteanne hospital in paris, france, is a powerful tool for defining the spatial and chronological evolution of an ictal discharge. These tutorial pages suppose you are comfortable with the basic concepts of megeeg analysis and source imaging. Figure 1 shows the results of the voxelbased overlap analysis of the epileptogenic zone. Ictal recruitment of anterior nucleus of thalamus in human. This is also the seizure location most amenable to. Surgery for epilepsy west, s 2019 cochrane library. Among the patients in this study, 8 presented with potentially epileptogenic lesions on preoperative mri, and 10 others were mrinegative in a phase i study. Based on these observations, it is hypothesized that there is a drugresistant epileptogenic zone drez which overlaps with the epileptogenic zone ez, and has both. Hemispherotomy is a surgical procedure of hemispheric disconnection which has a low rate. Example of preictal to ictal transitions in the epileptogenic zone. Patients with focal drugresistant epilepsy are potential candidates for surgery. The time frequency plot shows the proposed fingerprint. Localization of epileptogenic zone with the correction of. Epilepsy surgery download ebook pdf, epub, tuebl, mobi.
The ability to precisely localize the epileptogenic zone is crucial for surgical success. Stereoelectroencephalograph seeg is often considered as the gold standard to identify the epileptogenic zone ez that accounts for the onset and propagation of epileptiform discharges. Pdf the concept of drugresistant epileptogenic zone. Second, using an established seizure detection algorithm line lengthesteller.
Frontiers localization of the epileptogenic zone using. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a pdf plugin installed and enabled in your browser. Epilepsy is a disease that results in abnormal firing patterns in parts of the brain that comprise the epileptogenic network, known as the epileptogenic zone ez. In figures 3 and 4 f0 indicates bipolar frontooecipital leads. Identification of the epileptogenic zone from stereoeeg. In the dv group, the right medial temporal lobe, notably the hippocampus and parahippocampus, is maximally implicated in 10 of 16 patients centred at approximately montreal neurological institute mni x28, y. Read localization of epileptogenic zone based on graph analysis of stereoeeg, epilepsy research on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. The paucity of delta waves was somewhat against an expanding lesion.
Current literature in clinical science commentary monitoring with intracranial electrodes is the gold standard for identification of seizureonset zones and mapping of eloquent cortex in patients with intractable focal epilepsy. To get a quick overview of the software interface, you can watch this introduction video. This research focused on the development of a methodology for analysing electrophysiological intracranial eeg signals from patients with drugresistant focal epilepsy in order to support clinicians and surgeons in localizing the area responsible for seizure generation, organization and propagation, i. To establish epilepsy surgery in veterinary medicine, the concepts of the epileptogenic zone ez are essential. If youre not, we encourage you to read some background literature.
All eeg signals were recorded with the same 128channel amplifier. In other words, the epileptogenic zone cannot be defined. Intralesional recordings and epileptogenic zone in focal. Click download or read online button to get epilepsy surgery book now. In vivo metabotropic glutamate receptor type 5 abnormalities localize the epileptogenic zone in mesial temporal lobe epilepsy. Dti is used to detect microstructural changes in cortical devel. The surgical removal of the epileptogenic zone in medically intractable seizures depends on accurate localization to minimize the neurological sequelae and prevent future seizures. Eftu mt, efts mt, epileptogenic zone, refractory temporal lobe epilepsy introduction temporal lobe epilepsy tle is a chronic neuro. This site is like a library, use search box in the widget to get ebook that you want.
Several quantitative imaging metrics have been shown to localize the epileptogenic zone. Depth electrodes in pediatric epilepsy surgery canadian. Luders rosenow, luders, 2001, luders et al, 2006, with the epileptogenic zone defined as the minimum amount of cortex that must be resected or completely disconnected surgically to produce seizure freedom. Towards an eeg fingerprint for the epileptogenic zone. Lateralising value of experiential hallucinations in. Their epileptic seizures were processed to extract two potential biomarkers.
Brain injury and genetic abnormalities underlie this disorder. In other words, we speculated that the epileptogenic zone. In contrast, conventional electroencephalography eeg electrodes monitor this activity from outside the skull. Our ultimate goal was to establish the clinical value of.
This article is from frontiers in neurology, volume 4. Abstractin the context of focal drugresistant epilepsies, the surgical resection of the epileptogenic. Epilepsy james bowman,colorado state university, fort collins, colorado, usa f edward dudek,colorado state university, fort collins, colorado, usa mark spitz,university of colorado health science center, denver, colorado, usa epilepsy is a chronic neurological disorder characterized by recurrent epileptic seizures. Biomedical science and engineering 4 2011 788796 791 table 1. The total number of eeg signals is 300 100 normal signals, 100 interictal signals and 100 ictal signals. Stereoelectroencephalograph seeg is often considered as. Fast oscillations associated with interictal spikes. The impression was that there was an epileptogenic focus in the left frontal lobe involving the cortex. To date, few studies have demonstrated the use of depth electrodes in a pediatric epilepsy population.
Spect for localizing the epileptogenic zone in patients undergoing evaluation for epilepsy surgery. Basic definitions seizure from the latin sacireto take possession of is the clinical manifestation of an abnormal, excessive, hypersynchronous discharge of. The concepts of the epileptogenic zone were first described by hans o. Read intralesional recordings and epileptogenic zone in focal polymicrogyria, epilepsia on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Current methods to localize the ez for surgical treatment often require observations of hundreds of thousands of eeg data points measured from many electrodes implanted in a patient. Localization of epileptogenic zones in lennoxgastaut. Identification of the epileptogenic zone of temporal lobe. Localization of epileptogenic zone proceedings of the. The whole eeg data is composed of five sets denoted ae, each containing 100 sin. Electrocorticography ecog, or intracranial electroencephalography ieeg, is a type of electrophysiological monitoring that uses electrodes placed directly on the exposed surface of the brain to record electrical activity from the cerebral cortex. E pilepsy surgery is based on the principle that resection of the epileptogenic zone e. Current imaging modalities cannot successfully determine the epileptogenic zone ez, which is defined as the minimum amount of brain tissue.
In case of surgery, a minimum amount of cerebral cortex known as epileptogenic zone ez will be removed to achieve seizure freedom. The aim of this research is to apply an approach based on phase transfer entropy pte and graph theory to study the interactions between the stereoelectroencephalography seeg activities recorded in multilobar origin, in order to evaluate their ability to detect the epileptogenic zone ez of. Localization of the epileptogenic zone by ictal and interictal spect. Some polling questions for the audience b sensory andor motor evoked fields. Medicina free fulltext a novel noninvasive approach. The most common location of seizure onset in adults is the temporal lobe, especially the medial temporal lobe hippocampus. Restingstate seeg may help localize epileptogenic brain. View the article pdf and any associated supplements and figures for a period of 48. If you are looking for the old tutorials, they are still available here.
1477 1380 1230 962 1506 1410 856 191 322 769 1386 1321 612 1114 405 932 218 215 1381 495 1509 851 35 516 486 804 1505 648 494 824 840 85 1142 1179 291 697 1279 1002 99 365 589 553 890 1148 186 1121 1477