Objective: In focal epilepsies, the accurate delineation of the epileptogenic network is a fundamental step before surgery. For years, the relationship between the interictal epileptic spikes (defining the "irritative zone", IZ) and the sites of seizure initiation (SOZ) has been a matter of debate.
Methods: Our goal was to investigate from intracerebral recordings (stereoelectroencephalography, SEEG) the distribution of interictal epileptic spikes (based on a spike frequency index, SI) and the topography of the SOZ (based on the Epileptogenicity Index, EI) in patients having focal neocortical epilepsies. Thirty-one patients were studied. A total of 539 brain regions were quantified in term of both spike generation (SI) and seizure initiation (EI).
Results: We found a 56% (18/32) rate of agreement between maximal EI and maximal SI values. When considering separately patients with focal cortical dysplasia (FCD), the proportion of patients with good concordance was ∼75% (15/20), whereas it was only 33% (4/12) in the non FCD group.
Conclusions: Our results show that a significant part of patients have some dissociation between regions showing pronounced spiking activity and those showing high epileptogenicity. e is clinically important.
Significance: For patients with these dissociations, other markers than spiking frequency remain to be investigated. In the FCD group, the good concordance between SI and EI confirms that the mapping of the irritative zone is clinically important.
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http://dx.doi.org/10.1016/j.clinph.2015.10.029 | DOI Listing |
BMC Med Inform Decis Mak
January 2025
The First Affiliated Hospital, and College of Clinical Medicine of Henan University of Science and Technology, Luoyang, China.
Background: The diagnosis and treatment of epilepsy continue to face numerous challenges, highlighting the urgent need for the development of rapid, accurate, and non-invasive methods for seizure detection. In recent years, advancements in the analysis of electroencephalogram (EEG) signals have garnered widespread attention, particularly in the area of seizure recognition.
Methods: A novel hybrid deep learning approach that combines feature fusion for efficient seizure detection is proposed in this study.
Seizure
December 2024
University College Hospital, London, UK; UCL Queen Square Institute of Neurology: Department of Clinical and Experimental Epilepsy, London WC1N 3BG, UK. Electronic address:
Objective: Professional bodies recommend the use of performance validity tests (PVTs) to aid the interpretation of scores obtained in neuropsychological assessments, but base rates of failure differ according to neurological diagnosis and the associated impairments. This review summarises the PVT literature in people with epilepsy with the aim of establishing base rates of PVT failure and the factors associated with PVT performance in this population.
Methods: Ovid and PubMed databases were searched for studies reporting PVT test performance in people with epilepsy.
J Neurosurg Pediatr
January 2025
2Neurology, UT Southwestern, Dallas, Texas.
Objective: Patients with drug-resistant epilepsy (DRE) are often referred for phase II evaluation with stereo-electroencephalography (SEEG) to identify a seizure onset zone for guiding definitive treatment. For patients without a focal seizure onset zone, neuromodulation targeting the thalamic nuclei-specifically the centromedian nucleus, anterior nucleus of the thalamus, and pulvinar nucleus-may be considered. Currently, thalamic nuclei selection is based mainly on the location of seizure onset, without a detailed evaluation of their network involvement.
View Article and Find Full Text PDFFront Neurol
December 2024
Division of Neurology, Department of Pediatrics, McMaster Children's Hospital, Hamilton, ON, Canada.
Introduction: This study investigated low-density scalp electrical source imaging of the ictal onset zone and interictal spike ripple high-frequency oscillation networks using source coherence maps in the pediatric epilepsy surgical workup. Intracranial monitoring, the gold standard for determining epileptogenic zones, has limited spatial sampling. Source coherence analysis presents a promising new non-invasive technique.
View Article and Find Full Text PDFSci Rep
December 2024
INSERM, INS, Inst Neurosci Syst, Aix Marseille Univ, Marseille, France.
Post-traumatic stress disorder (PTSD) is more common in patients with drug-resistant epilepsy. Some of these patients experience PTSD due to early psychotraumatic events. This study aims to assess the influence of PTSD on interictal functional connectivity using stereoelectroencephalography (SEEG) recordings in patients with temporal lobe DRE (TDRE).
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