Clinically Localized Seizure Focus Maybe Not Exactly the Position of Abating Seizures: A Computational Evidence

Abstract Seizure focus localization is the key to control seizures. However, in this paper, we show that the clinically localized seizure focus may be not exactly the positions to abate seizures. Firstly, the reliability of a previously proposed methodology employed to estimate the synchronicity and directionality of information flows over time between EEG signals, is numerically assessed with a coupled mass neural model. Then 10 channels' EEG signals from a patient with focal epilepsy are used to reconstruct the dynamical complex network of pathological seizure. This may facilitate to identify the evolution paths of information flows and localize the potential seizure foci. What's more, based on the controllability and observability principles of complex systems, we can focus on the key nodes which is effective to control the network seizure behaviors and the key ones that can allow us to estimate the state of all other variables. Results show that to fully control the epileptic network may not just be related to the focus zone, it may also involves in other non-focus nodes. In addition, we use the spatiotemporal neural network model connected by our modeled dynamical adjacent matrix to successfully reproduce the original EEG signals which can be effectively abated by applying the normal distribution noise stimulation with cathodic phase pulses (cNDNs) on the identified key nodes or resecting them. Our results enrich the clinical results and provide new insights into the seizure resection and electronic stimulation therapies.

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Cortical thickness in childhood left focal epilepsy: Thinning beyond the seizure focus

Epilepsy & Behavior ◽

10.1016/j.yebeh.2019.106825 ◽

2020 ◽

Vol 102 ◽

pp. 106825 ◽

Cited By ~ 1

Author(s):

Emanuel M. Boutzoukas ◽

Jason Crutcher ◽

Eduardo Somoza ◽

Leigh N. Sepeta ◽

Xiaozhen You ◽

...

Keyword(s):

Cortical Thickness ◽

Focal Epilepsy ◽

Seizure Focus

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Estimation of time delay between EEG signals for epileptic focus localization: statistical error considerations

Electroencephalography and Clinical Neurophysiology ◽

10.1016/0013-4694(91)90109-h ◽

1991 ◽

Vol 78 (2) ◽

pp. 105-110 ◽

Cited By ~ 11

Author(s):

P.Y. Ktonas ◽

R. Mallart

Keyword(s):

Time Delay ◽

Statistical Error ◽

Epileptic Focus ◽

Eeg Signals ◽

Focus Localization ◽

Estimation Of Time

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Surgical management of epilepsy using epidural recordings to localize the seizure focus

Journal of Neurosurgery ◽

10.3171/jns.1984.60.3.0457 ◽

1984 ◽

Vol 60 (3) ◽

pp. 457-466 ◽

Cited By ~ 163

Author(s):

Sidney Goldring ◽

Erik M. Gregorie

Keyword(s):

Temporal Lobe ◽

Focal Epilepsy ◽

Temporal Lobectomy ◽

Epileptogenic Focus ◽

Electrode Arrays ◽

Content Type ◽

Seizure Focus ◽

Depth Electrodes ◽

Sensory Evoked ◽

Fine Print

✓ One hundred patients with focal epilepsy (44 were children) were evaluated with extraoperative electrocorticography via epidural electrode arrays. Localization of the epileptogenic focus was derived predominantly from recordings made during spontaneously occurring seizures. All resection procedures were carried out under general anesthesia. During anesthesia, the recording of sensory evoked responses made it possible to readily identify the sensorimotor region. Of the 100 patients, 72 underwent resection of an epileptogenic focus, and 33 of these were children. Those who did not have a resection either exhibited a diffuse seizure focus, failed to show an electrical seizure discharge in association with the clinical seizure, failed to have a seizure during the period of monitoring, or failed to exhibit conclusive changes for identifying a focus in the interictal record. Fifty-seven patients (29 children and 28 adults) who had a resection have been followed for between 1 and 12 years. Eighteen (62%) of the 29 children and 18 (64%) of the 28 adults enjoyed a good result. Twenty of the 100 patients reported here had temporal lobe epilepsy. They were candidates for recordings with depth electrodes to identify their focus, but they were evaluated instead with epidural recordings; the method is described. In 15 of them, a unilateral focus was identified and they underwent an anterior temporal lobectomy. Pathological changes were found in every case and, in 11 patients, the epidural recordings distinguished between a medial and a lateral focus. Ten of these patients have been followed for 9 months to 3½ years, and seven have had a good result. The observations suggest that epidural electrodes may be used in lieu of depth electrodes for identifying the symptomatic temporal lobe.

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Reconstruction of Neural Activity from EEG Data Using Dynamic Spatiotemporal Constraints

International Journal of Neural Systems ◽

10.1142/s012906571650026x ◽

2016 ◽

Vol 26 (07) ◽

pp. 1650026 ◽

Cited By ~ 16

Author(s):

E. Giraldo-Suarez ◽

J. D. Martinez-Vargas ◽

G. Castellanos-Dominguez

Keyword(s):

Spatial Resolution ◽

Neural Activity ◽

Focal Epilepsy ◽

Experimental Testing ◽

Brain Activity ◽

Brain Regions ◽

Basis Set ◽

Eeg Signals ◽

Reconstruction Performance ◽

Eeg Data

We present a novel iterative regularized algorithm (IRA) for neural activity reconstruction that explicitly includes spatiotemporal constraints, performing a trade-off between space and time resolutions. For improving the spatial accuracy provided by electroencephalography (EEG) signals, we explore a basis set that describes the smooth, localized areas of potentially active brain regions. In turn, we enhance the time resolution by adding the Markovian assumption for brain activity estimation at each time period. Moreover, to deal with applications that have either distributed or localized neural activity, the spatiotemporal constraints are expressed through [Formula: see text] and [Formula: see text] norms, respectively. For the purpose of validation, we estimate the neural reconstruction performance in time and space separately. Experimental testing is carried out on artificial data, simulating stationary and non-stationary EEG signals. Also, validation is accomplished on two real-world databases, one holding Evoked Potentials and another with EEG data of focal epilepsy. Moreover, responses of functional magnetic resonance imaging for the former EEG data have been measured in advance, allowing to contrast our findings. Obtained results show that the [Formula: see text]-based IRA produces a spatial resolution that is comparable to the one achieved by some widely used sparse-based estimators of brain activity. At the same time, the [Formula: see text]-based IRA outperforms other similar smooth solutions, providing a spatial resolution that is lower than the sparse [Formula: see text]-based solution. As a result, the proposed IRA is a promising method for improving the accuracy of brain activity reconstruction.

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Automatic and Remote Controlled Ictal SPECT Injection for Seizure Focus Localization by Use of a Commercial Contrast Agent Application Pump

Epilepsia ◽

10.1111/j.1528-1167.2007.01054.x ◽

2007 ◽

Vol 48 (7) ◽

pp. 1409-1413 ◽

Cited By ~ 9

Author(s):

Michael Feichtinger ◽

Hans Eder ◽

Alexander Holl ◽

Eva Körner ◽

Gerda Zmugg ◽

...

Keyword(s):

Contrast Agent ◽

Ictal Spect ◽

Seizure Focus ◽

Focus Localization

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INTELLIGENCE LEVEL MIGHT BE PREDICTED BY THE CHARACTERISTICS OF EEG SIGNALS AT SPECIFIC FREQUENCIES AND BRAIN REGIONS

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519421400479 ◽

2021 ◽

pp. 2140047

Author(s):

SONG LUO ◽

RUI CHEN ◽

ZHENGTING YANG ◽

KUN LI

Keyword(s):

Total Energy ◽

Distribution Patterns ◽

Brain Regions ◽

Information Flows ◽

Research Subjects ◽

Eeg Signals ◽

Long Distance ◽

Adult Intelligence Scale ◽

Intellectual Activity ◽

Intelligence Level

The total energy the brain consumed and the intensities of information flows across different brain regions in an intellectual activity may help to explain an individual’s intelligence level. To verify this assumption, 43 students aged 18–25 were recruited as the research subjects. Their intelligence quotients (IQ) were scored by using Wechsler Adult Intelligence Scale (WAIS), while their electroencephalogram (EEG) signals were recorded simultaneously by using Neuroscan system. The total energy and distribution patterns of EEG signals were acquired in Curry 8.0. The intensities of information flow across different brain regions were measured by Phase Slope Index (PSI). 20 channels and 190 channel combinations were selected for data analysis. The results show that the IQ score negatively correlates to the EEG energy and positively correlates to the intensities of information flows at specific frequency bands in specific channel pairs, especially in some long distance (18–24[Formula: see text]cm) channel pairs.

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Clinical results and prospects for the use of phenosanic acid in patients with focal epilepsy

Zhurnal nevrologii i psikhiatrii im S S Korsakova ◽

10.17116/jnevro202112110152 ◽

2021 ◽

Vol 121 (10) ◽

pp. 52

Author(s):

S.G. Burd ◽

A.V. Lebedeva ◽

N.V. Pantina ◽

Yu.V. Rubleva ◽

N.V. Pizova ◽

...

Keyword(s):

Focal Epilepsy ◽

Clinical Results

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Epileptic Slow Wave Activity

Fifty Years of Magnetoencephalography ◽

10.1093/oso/9780190935689.003.0014 ◽

2020 ◽

pp. 198-208

Author(s):

Stefan Rampp ◽

Martin Kaltenhäuser

Keyword(s):

Epilepsy Surgery ◽

Focal Epilepsy ◽

Activity Analysis ◽

Wave Activity ◽

Slow Wave Activity ◽

Interictal Spikes ◽

Intracranial Surgery ◽

Potential Value ◽

Focus Localization ◽

Slow Activity

In recent years, novel markers for the epileptic network beyond interictal spikes and ictal seizure correlates have been described. Slow activity in theta, delta, and lower frequency ranges have been detected using invasive electroencephalography (EEG) and noninvasive magnetoencephalography (MEG)/EEG. While such activity also occurs that is associated, for example, with large lesions and after intracranial surgery, certain subtypes may be used to localize the epileptic network. This chapter provides an overview of MEG slow frequency markers in patients with focal epilepsy. It covers the application of slow activity–based focus localization in patients undergoing workup for epilepsy surgery and discusses the relation to conventional spike-based analysis as well as the potential value of slow activity analysis in patients with previous surgery and persisting or recurring seizures.

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