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Lu G, Cheng Y, Wang Y, Hu J, Zhang F, Li W, Xia M, Lu X, Yang W. The Prevalence and Risk Factors of Electrical Status Epilepticus During Slow-Wave Sleep in Self-Limited Epilepsy With Centrotemporal Spikes. Clin EEG Neurosci 2024; 55:265-271. [PMID: 37331959 DOI: 10.1177/15500594231182758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Objective. To investigate the prevalence and risk factors for electrical status epilepticus during slow-wave sleep (ESES) in patients with self-limited epilepsy with centrotemporal spikes (SeLECTS). Methods. The clinical and follow-up data of children with SeLECTS were collected between 2017 and 2021. Patients were divided into typical ESES, atypical ESES, and non-ESES groups according to spike-wave indices (SWI). Clinical and electroencephalography characteristics were retrospectively analyzed. Logistic regression was used to identify risk factors for ESES. Results. A total of 95 patients with SeLECTS were enrolled. Seven patients (7.4%) developed typical ESES, 30 (31.6%) developed atypical ESES, 25 (26.3%) developed ESES at the first visit, and 12 (12.6%) developed ESES during treatment and follow-up. Multivariate logistic regression analysis showed that the risk factors for SeLECTS combined with ESES were Rolandic double or multiple spikes (OR = 8.626, 95% CI: 2.644-28.147, P < .001) and Rolandic slow waves (OR = 53.550, 95% CI: 6.339-452.368, P < .001). There were no significant differences in seizure characteristics, electroencephalogram (EEG) findings, or cognitive impairment between the atypical and typical ESES groups. Conclusion. More than one-third of the SeLECTS patients combined with ESES. Both atypical and typical ESES scores can affect cognitive function. On electroencephalography, interictal Rolandic double/multiple spikes and slow-wave abnormalities may indicate SeLECTS with ESES.
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Affiliation(s)
- Guangshuang Lu
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Yun Cheng
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Yun Wang
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Jie Hu
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Fan Zhang
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Wenbo Li
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Minnong Xia
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Xiaoyan Lu
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
| | - Wu Yang
- Department of Pediatrics, The Lu'an Hospital Affiliated to Anhui Medical University, The Lu'an People's Hospital, Lu'an, China
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Fujita T, Ihara Y, Hayashi H, Inoue T, Nagamitsu S, Yasumoto S, Tobimatsu S. Scalp EEG-recorded high-frequency oscillations can predict seizure activity in Panayiotopoulos syndrome. Clin Neurophysiol 2023; 156:106-112. [PMID: 37918221 DOI: 10.1016/j.clinph.2023.09.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 08/16/2023] [Accepted: 09/12/2023] [Indexed: 11/04/2023]
Abstract
OBJECTIVE We studied the relationship between the clinical course of Panayiotopoulos syndrome (PS) and high-frequency oscillations (HFOs) captured during interictal scalp electroencephalography (EEG) to determine the feasibility of using HFOs to detect seizure activity in PS. METHODS We analyzed the interictal scalp EEGs of 18 children with PS. Age parameters, seizure frequencies, and antiepileptic drugs were compared between the HFO-positive (HFOPG) and HFO-negative (HFONG) groups. RESULTS Thirteen patients (72.2%) had HFOs while five patients (27.8%) had no HFOs in 194 interictal EEG records. We found no statistically significant differences in the mean age of epilepsy onset and last seizure, seizure frequency, or frequency of status epilepticus. However, the seizure activity period of the HFOPG was significantly longer than that of the HFONG. Patients with an HFO duration longer than 2 years were intractable to treatment. In most cases, seizures did not occur in the absence of HFOs, even when the spikes remained. CONCLUSIONS HFOs are related to the seizure activity period in patients with PS. SIGNIFICANCE We propose that HFOs are a biomarker of epileptogenicity and an indicator for drug reduction because seizures did not occur if HFOs disappeared even if the spikes remained.
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Affiliation(s)
- Takako Fujita
- Department of Pediatrics, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Yukiko Ihara
- Department of Pediatrics, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Hitomi Hayashi
- Department of Pediatrics, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Takahito Inoue
- Department of Pediatrics, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Shinichiro Nagamitsu
- Department of Pediatrics, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Sawa Yasumoto
- Center of Medical Education, Faculty of Medicine, Fukuoka University, 7-45-1 Nanakuma, Jyounan-ku, Fukuoka 814-0180, Japan.
| | - Shozo Tobimatsu
- Department of Orthoptics, Faculty of Medicine, Fukuoka International University of Health and Welfare, 3-6-40 Momochihama, Sawara-ku, Fukuoka 814-0001, Japan.
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Takagi S. Exploring Ripple Waves in the Human Brain. Clin EEG Neurosci 2023; 54:594-600. [PMID: 34287087 DOI: 10.1177/15500594211034371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ripples are brief (<150 ms) high-frequency oscillatory neural activities in the brain with a range of 140 to 200 Hz in rodents and 80 to 140 Hz in humans. Ripples are regarded as playing an essential role in several aspects of memory function, mainly in the hippocampus. This type of ripple generally occurs with sharp waves and is called a sharp-wave ripple (SPW-R). Extensive research of SPW-Rs in the rodent brain while actively awake has also linked the function of these SPW-Rs to navigation and decision making. Although many studies with rodents unveiled SPW-R function, research in humans on this subject is still sparse. Therefore, unveiling SPW-R function in the human hippocampus is warranted. A certain type of ripples may also be a biomarker of epilepsy. This type of ripple is called a pathological ripple (p-ripple). p-ripples have a wider range of frequency (80-500 Hz) than SPW-Rs, and the range of frequency is especially higher in brain regions that are intrinsically linked to epilepsy onset. Brain regions producing ripples are too small for scalp electrode recording, and intracranial recording is typically needed to detect ripples. In addition, SPW-Rs in the human hippocampus have been recorded from patients with epilepsy who may have p-ripples. Differentiating SPW-Rs and p-ripples is often not easy. We need to develop more sophisticated methods to record SPW-Rs to differentiate them from p-ripples. This paper reviews the general features and roles of ripple waves.
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Affiliation(s)
- Shunsuke Takagi
- Department of Psychiatry and Behavioral Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyo-ku, Japan
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Maeda K, Hosoda N, Fukumoto J, Kawai S, Hayafuji M, Tsuboi H, Fujita S, Ichino N, Osakabe K, Sugimoto K, Ishihara N. Association of Scalp High-Frequency Oscillation Detection and Characteristics With Disease Activity in Pediatric Epilepsy. J Clin Neurophysiol 2023:00004691-990000000-00106. [PMID: 37934062 DOI: 10.1097/wnp.0000000000001052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023] Open
Abstract
INTRODUCTION High-frequency oscillation (HFO) in scalp electroencephalography is a promising new noninvasive prognostic epilepsy biomarker, but further data are needed to ascertain the utility of this parameter. The present work investigated the association between epileptic activity and scalp HFO in pediatric patients with various types of epilepsy, using multivariable regression models to correct for possible confounding factors. METHODS The authors analyzed 97 subjects who were divided into groups with active epilepsy (within 1 year of seizure), seizure-free epilepsy (>1 year without seizure), and nonepilepsy. Regarding the frequency of seizure occurrence as an indicator of epileptic activity, we categorized subjects into four groups (Daily/Weekly, Monthly, Yearly, and Rarely). RESULTS Multiple linear regression analysis showed that the scalp HFO detection rate was significantly higher in patients with active epilepsy than in those with nonepilepsy (β [95% confidence interval] = 2.77 [1.79-4.29]; P < 0.001). The association between scalp HFO detection rate and frequency of seizure occurrence was highest in the Daily/Weekly group (β [95% confidence interval] = 3.38 [1.57-7.27]; P = 0.002), followed by Monthly and Yearly groups (β [95% confidence interval] = 2.42 [1.02-5.73]; P = 0.046 and 0.36 [0.16-0.83]; P = 0.017). In addition, HFO duration, number of peaks, and number of channels detected were significantly higher in patients with active epilepsy. CONCLUSIONS Pediatric patients with active epilepsy and high frequency of seizure occurrence exhibited a higher scalp HFO detection rate. These results may help to establish HFO detectable by noninvasive scalp electroencephalography as a biomarker of active epilepsy in pediatric patients.
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Affiliation(s)
- Keisuke Maeda
- Department of Clinical Physiology, Fujita Health University School of Medical Sciences, Toyoake, Japan
| | - Nami Hosoda
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Junichi Fukumoto
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Shun Kawai
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Mizuki Hayafuji
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Himari Tsuboi
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Shiho Fujita
- Department of Clinical Laboratory, Fujita Health University Hospital, Toyoake, Japan
| | - Naohiro Ichino
- Department of Clinical Physiology, Fujita Health University School of Medical Sciences, Toyoake, Japan
| | - Keisuke Osakabe
- Department of Clinical Physiology, Fujita Health University School of Medical Sciences, Toyoake, Japan
| | - Keiko Sugimoto
- Department of Medical Sciences Education, Fujita Health University School of Medical Sciences, Toyoake, Japan; and
| | - Naoko Ishihara
- Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Japan
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Ji Y, Zhang J, Lu H, Yang H, Zhang X, Liu H, Liu W, Zhou W, Zhang X, Sun W. Correlation between scalp high-frequency oscillations and prognosis in patients with benign epilepsy of childhood with centrotemporal spikes. CNS Neurosci Ther 2023; 29:3053-3061. [PMID: 37157892 PMCID: PMC10493670 DOI: 10.1111/cns.14246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/03/2023] [Accepted: 04/16/2023] [Indexed: 05/10/2023] Open
Abstract
AIMS The study aimed to explore whether high-frequency oscillations (HFOs) can predict seizure risk and atypical manifestations of benign epilepsy of childhood with centrotemporal spikes (BECTS). METHODS We recruited 60 patients and divided them into three groups: (1) seizure-free BECTS, (2) active typical BECTS, and (3) active atypical forms of BECTS. Electroencephalogram was used to record the number, location, average amplitude, and duration of spikes, and spike ripples were analyzed using time-frequency technology. Multivariable logistic regression analysis was used to investigate independent predictive factors for prognosis. RESULTS The number of sleep spike ripples, rather than spikes, was an independent risk factor for the active period of the disease (odds ratio [OR] = 4.714, p = 0.003) and atypical forms of BECTS (OR = 1.455, p = 0.049); the optimal thresholds for the spike ripple rate were >0 (area under the curve [AUC] = 0.885, sensitivity = 96.15%, specificity = 73.33%) and >0.6/min (AUC = 0.936, sensitivity = 84.21%, specificity = 96.15%), respectively. Furthermore, in typical BECTS, the spike ripple rate showed significant negative correlations with time since the last seizure (ρ = -0.409, p = 0.009) and age (ρ = -0.379, p = 0.016), while the spike rate did not. CONCLUSION Spike ripple was a marker for distinguishing typical and atypical forms of BECTS and reflected the risk of seizure recurrence better than the spike alone. The present findings might assist clinicians in BECTS treatment.
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Affiliation(s)
- Yichen Ji
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Jun Zhang
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Hongjuan Lu
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Haoran Yang
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Xuan Zhang
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Huixin Liu
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Wenjian Liu
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
| | - Wei Zhou
- Department of NeurologyMine HospitalXuzhouChina
| | | | - Wei Sun
- Department of NeurologyXuanwu Hospital Capital Medical UniversityBeijingChina
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Halász P, Szũcs A. Self-limited childhood epilepsies are disorders of the perisylvian communication system, carrying the risk of progress to epileptic encephalopathies-Critical review. Front Neurol 2023; 14:1092244. [PMID: 37388546 PMCID: PMC10301767 DOI: 10.3389/fneur.2023.1092244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/04/2023] [Indexed: 07/01/2023] Open
Abstract
"Sleep plasticity is a double-edged sword: a powerful machinery of neural build-up, with a risk to epileptic derailment." We aimed to review the types of self-limited focal epilepsies..."i.e. keep as two separate paragraphs" We aimed to review the types of self-limited focal epilepsies: (1) self-limited focal childhood epilepsy with centrotemporal spikes, (2) atypical Rolandic epilepsy, and (3) electrical status epilepticus in sleep with mental consequences, including Landau-Kleffner-type acquired aphasia, showing their spectral relationship and discussing the debated topics. Our endeavor is to support the system epilepsy concept in this group of epilepsies, using them as models for epileptogenesis in general. The spectral continuity of the involved conditions is evidenced by several features: language impairment, the overarching presence of centrotemporal spikes and ripples (with changing electromorphology across the spectrum), the essential timely and spatial independence of interictal epileptic discharges from seizures, NREM sleep relatedness, and the existence of the intermediate-severity "atypical" forms. These epilepsies might be the consequences of a genetically determined transitory developmental failure, reflected by widespread neuropsychological symptoms originating from the perisylvian network that have distinct time and space relations from secondary epilepsy itself. The involved epilepsies carry the risk of progression to severe, potentially irreversible encephalopathic forms.
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Affiliation(s)
- Péter Halász
- Department of Neurology, University Medical School, Pécs, Hungary
| | - Anna Szũcs
- Institute of Behavioral Sciences, Semmelweis University, Budapest, Hungary
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Chinappen DM, Xiao G, Jing J, Spencer ER, Eden UT, Kramer MA, Westover MB, Chu CJ. Spike height improves prediction of future seizure risk. Clin Neurophysiol 2023; 150:49-55. [PMID: 37002980 PMCID: PMC10192090 DOI: 10.1016/j.clinph.2023.02.180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/03/2023] [Accepted: 02/20/2023] [Indexed: 04/01/2023]
Abstract
OBJECTIVE We evaluated whether interictal epileptiform discharge (IED) rate and morphological characteristics predict seizure risk. METHODS We evaluated 10 features from automatically detectable IEDs in a stereotyped population with self-limited epilepsy with centrotemporal spikes (SeLECTS). We tested whether the average value or the most extreme values from each feature predicted future seizure risk in cross-sectional and longitudinal models. RESULTS 10,748 individual centrotemporal IEDs were analyzed from 59 subjects at 81 timepoints. In cross-sectional models, increases in average spike height, spike duration, slow wave rising slope, slow wave falling slope, and the most extreme values of slow wave rising slope each improved prediction of an increased risk of a future seizure compared to a model with age alone (p < 0.05, each). In longitudinal model, spike rising height improved prediction of future seizure risk compared to a model with age alone (p = 0.04) CONCLUSIONS: Spike height improves prediction of future seizure risk in SeLECTS. Several other morphological features may also improve prediction and should be explored in larger studies. SIGNIFICANCE Discovery of a relationship between novel IED features and seizure risk may improve clinical prognostication, visual and automated IED detection strategies, and provide insights into the underlying neuronal mechanisms that contribute to IED pathology.
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Affiliation(s)
- D M Chinappen
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Graduate Program for Neuroscience, Boston University, Boston, MA, USA; Department of Mathematics and Statistics, and Center for Systems Neuroscience, Boston University, Boston, MA, USA.
| | - G Xiao
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Johns Hopkins University School of Medicine, Baltimore, MD, USA; Harvard University, Cambridge, MA, USA.
| | - J Jing
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Harvard Medical School, Boston, MA, USA.
| | - E R Spencer
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Graduate Program for Neuroscience, Boston University, Boston, MA, USA.
| | - U T Eden
- Department of Mathematics and Statistics, and Center for Systems Neuroscience, Boston University, Boston, MA, USA.
| | - M A Kramer
- Department of Mathematics and Statistics, and Center for Systems Neuroscience, Boston University, Boston, MA, USA.
| | - M B Westover
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Harvard Medical School, Boston, MA, USA.
| | - C J Chu
- Massachusetts General Hospital, Department of Neurology, Boston, MA 02114, USA; Harvard Medical School, Boston, MA, USA.
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Kuhnke N, Wusthoff CJ, Swarnalingam E, Yanoussi M, Jacobs J. Epileptic high-frequency oscillations occur in neonates with a high risk for seizures. Front Neurol 2023; 13:1048629. [PMID: 36686542 PMCID: PMC9848430 DOI: 10.3389/fneur.2022.1048629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/30/2022] [Indexed: 01/05/2023] Open
Abstract
Introduction Scalp high-frequency oscillations (HFOs, 80-250 Hz) are increasingly recognized as EEG markers of epileptic brain activity. It is, however, unclear what level of brain maturity is necessary to generate these oscillations. Many studies have reported the occurrence of scalp HFOs in children with a correlation between treatment success of epileptic seizures and the reduction of HFOs. More recent studies describe the reliable detection of HFOs on scalp EEG during the neonatal period. Methods In the present study, continuous EEGs of 38 neonates at risk for seizures were analyzed visually for the scalp HFOs using 30 min of quiet sleep EEG. EEGs of 14 patients were of acceptable quality to analyze HFOs. Results The average rate of HFOs was 0.34 ± 0.46/min. About 3.2% of HFOs occurred associated with epileptic spikes. HFOs were significantly more frequent in EEGs with abnormal vs. normal background activities (p = 0.005). Discussion Neonatal brains are capable of generating HFOs. HFO could be a viable biomarker for neonates at risk of developing seizures. Our preliminary data suggest that HFOs mainly occur in those neonates who have altered background activity. Larger data sets are needed to conclude whether HFO occurrence is linked to seizure generation and whether this might predict the development of epilepsy.
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Affiliation(s)
- Nicola Kuhnke
- Department of Pediatric Neurology and Muscular Disease, University Medical Center, Freiburg, Germany
| | | | - Eroshini Swarnalingam
- Department of Pediatrics, University of Calgary, Alberta Children's Hospital, Calgary, AB, Canada
| | - Mina Yanoussi
- Department of Pediatric Neurology and Muscular Disease, University Medical Center, Freiburg, Germany
| | - Julia Jacobs
- Department of Pediatrics, University of Calgary, Alberta Children's Hospital, Calgary, AB, Canada,*Correspondence: Julia Jacobs ✉
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Accurate differentiation between physiological and pathological ripples recorded by scalp-EEG. Clin Neurophysiol 2022; 143:172-181. [DOI: 10.1016/j.clinph.2022.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/21/2022] [Accepted: 08/16/2022] [Indexed: 11/18/2022]
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High-frequency oscillations in scalp EEG: A systematic review of methodological choices and clinical findings. Clin Neurophysiol 2022; 137:46-58. [DOI: 10.1016/j.clinph.2021.12.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/13/2021] [Accepted: 12/21/2021] [Indexed: 02/08/2023]
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Santana‐Gomez CE, Engel J, Staba R. Drug-resistant epilepsy and the hypothesis of intrinsic severity: What about the high-frequency oscillations? Epilepsia Open 2021; 7 Suppl 1:S59-S67. [PMID: 34861102 PMCID: PMC9340307 DOI: 10.1002/epi4.12565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 11/19/2022] Open
Abstract
Drug‐resistant epilepsy (DRE) affects approximately one‐third of the patients with epilepsy. Based on experimental findings from animal models and brain tissue from patients with DRE, different hypotheses have been proposed to explain the cause(s) of drug resistance. One is the intrinsic severity hypothesis that posits that drug resistance is an inherent property of epilepsy related to disease severity. Seizure frequency is one measure of epilepsy severity, but frequency alone is an incomplete measure of severity and does not fully explain basic research and clinical studies on drug resistance; thus, other measures of epilepsy severity are needed. One such measure could be pathological high‐frequency oscillations (HFOs), which are believed to reflect the neuronal disturbances responsible for the development of epilepsy and the generation of spontaneous seizures. In this manuscript, we will briefly review the intrinsic severity hypothesis, describe basic and clinical research on HFOs in the epileptic brain, and based on this evidence discuss whether HFOs could be a clinical measure of epilepsy severity. Understanding the mechanisms of DRE is critical for producing breakthroughs in the development and testing of novel strategies for treatment.
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Affiliation(s)
| | - Jerome Engel
- Department of NeurologyDavid Geffen School of Medicine at UCLALos AngelesCaliforniaUSA
- Brain Research InstituteDavid Geffen School of Medicine at UCLALos AngelesCaliforniaUSA
- Department of NeurobiologyDavid Geffen School of Medicine at UCLALos AngelesCaliforniaUSA
- Department of Psychiatry and Biobehavioral SciencesDavid Geffen School of Medicine at UCLALos AngelesCaliforniaUSA
| | - Richard Staba
- Department of NeurologyDavid Geffen School of Medicine at UCLALos AngelesCaliforniaUSA
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Sun Y, Ren G, Ren J, Wang Q. High-frequency oscillations detected by electroencephalography as biomarkers to evaluate treatment outcome, mirror pathological severity and predict susceptibility to epilepsy. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-021-00063-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractHigh-frequency oscillations (HFOs) in the electroencephalography (EEG) have been extensively investigated as a potential biomarker of epileptogenic zones. The understanding of the role of HFOs in epilepsy has been advanced considerably over the past decade, and the use of scalp EEG facilitates recordings of HFOs. HFOs were initially applied in large scale in epilepsy surgery and are now being utilized in other applications. In this review, we summarize applications of HFOs in 3 subtopics: (1) HFOs as biomarkers to evaluate epilepsy treatment outcome; (2) HFOs as biomarkers to measure seizure propensity; (3) HFOs as biomarkers to reflect the pathological severity of epilepsy. Nevertheless, knowledge regarding the above clinical applications of HFOs remains limited at present. Further validation through prospective studies is required for its reliable application in the clinical management of individual epileptic patients.
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Oka M, Kobayashi K, Shibata T, Tsuchiya H, Hanaoka Y, Akiyama M, Morooka T, Matsuhashi M, Akiyama T. A study on the relationship between non-epileptic fast (40 - 200 Hz) oscillations in scalp EEG and development in children. Brain Dev 2021; 43:904-911. [PMID: 34052035 DOI: 10.1016/j.braindev.2021.05.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/17/2021] [Accepted: 05/06/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Physiological gamma and ripple activities may be linked to neurocognitive functions. This study investigated the relationship between development and non-epileptic, probably physiological, fast (40-200 Hz) oscillations (FOs) including gamma (40 - 80 Hz) and ripple (80 - 200 Hz) oscillations in scalp EEG in children with neurodevelopmental disorders. METHODS Participants were 124 children with autism spectrum disorder (ASD) and/or attention deficit/hyperactivity disorder (ADHD). Gamma and ripple oscillations were explored from 60-second-long sleep EEG data in each subject using a semi-automatic detection tool supplemented with visual confirmation and time-frequency analysis. RESULTS Gamma and ripple oscillations were detected in 25 (20.2%) and 22 (17.7%) children, respectively. The observation of one or more occurrence(s) of ripple oscillations, but not gamma oscillations, was significantly related to lower age at EEG recording (odds ratio, OR: 0.727 [95% confidence interval, CI: 0.568-0.929]), higher intelligence/developmental quotient (OR: 1.041, 95% CI: 1.002-1.082), and lack of a diagnosis with ADHD (OR: 0.191, 95% CI: 0.039 - 0.937) according to a binominal logistic regression analysis that included diagnosis with ASD, sex, history of perinatal complications, history of febrile seizures, and use of a sedative agent for the EEG recording as the other non-significant parameters. Diagnostic group was not related to frequency or power of spectral peaks of FOs. CONCLUSION The production of non-epileptic scalp ripples was confirmed to be associated with brain development and function/dysfunction in childhood. Further investigation is necessary to interpret all of the information on higher brain functions that may be embedded in scalp FOs.
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Affiliation(s)
- Makio Oka
- Department of Psychosocial Medicine, National Center for Child Health and Development, Tokyo, Japan; Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Katsuhiro Kobayashi
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan.
| | - Takashi Shibata
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Hiroki Tsuchiya
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Yoshiyuki Hanaoka
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Mari Akiyama
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Teruko Morooka
- Division of Medical Support, Okayama University Hospital, Okayama, Japan
| | - Masao Matsuhashi
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Tomoyuki Akiyama
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
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14
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Lee CH, Le JT, Swann JW. Brain state-dependent high-frequency activity as a biomarker for abnormal neocortical networks in an epileptic spasms animal model. Epilepsia 2021; 62:2263-2273. [PMID: 34258765 DOI: 10.1111/epi.17008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Epileptic spasms are a hallmark of a severe epileptic state. A previous study showed neocortical up and down states defined by unit activity play a role in the generation of spasms. However, recording unit activity is challenging in clinical settings, and more accessible neurophysiological signals are needed for the analysis of these brain states. METHODS In the tetrodotoxin model, we used 16-channel microarrays to record electrophysiological activity in the neocortex during interictal periods and spasms. High-frequency activity (HFA) in the frequency range of fast ripples (200-500 Hz) was analyzed, as were slow wave oscillations (1-8 Hz), and correlated with the neocortical up and down states defined by multiunit activity (MUA). RESULTS HFA and MUA had high temporal correlation during interictal and ictal periods. Both increased strikingly during interictal up states and ictal events but were silenced during interictal down states and preictal pauses, and their distributions were clustered at the peak of slow oscillations in local field potential recordings. In addition, both HFA power and MUA firing rates were increased to a greater extent during spasms than interictal up states. During non-rapid eye movement sleep, the HFA rhythmicity faithfully followed the MUA up and down states, but during rapid eye movement sleep when MUA up and down states disappeared the HFA rhythmicity was largely absent. We also observed an increase in the number of HFA down state minutes prior to ictal onset, consistent with the results from analyses of MUA down states. SIGNIFICANCE This study provides evidence that HFA may serve as a biomarker for the pathological up states of epileptic spasms. The availability of HFA recordings makes this a clinically practical technique. These findings will likely provide a novel approach for localizing and studying epileptogenic neocortical networks not only in spasms patients but also in other types of epilepsy.
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Affiliation(s)
- Chih-Hong Lee
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
- Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, USA
- Department of Neurology, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - John T Le
- Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - John W Swann
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
- Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, Texas, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
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15
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El Shakankiry H, Arnold ST. High-Frequency Oscillations on Interictal Epileptiform Discharges in Routinely Acquired Scalp EEG: Can It Be Used as a Prognostic Marker? Front Hum Neurosci 2021; 15:709836. [PMID: 34393743 PMCID: PMC8362617 DOI: 10.3389/fnhum.2021.709836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 06/28/2021] [Indexed: 11/28/2022] Open
Abstract
Introduction Despite all the efforts for optimizing epilepsy management in children over the past decades, there is no clear consensus regarding whether to treat or not to treat epileptiform discharges (EDs) after a first unprovoked seizure or the optimal duration of therapy with anti-seizure medication (ASM). It is therefore highly needed to find markers on scalp electroencephalogram (EEG) that can help identify pathological EEG discharges that require treatment. Aim of the study This retrospective study aimed to identify whether the coexistence of ripples/high-frequency oscillations (HFOs) with interictal EDs (IEDs) in routinely acquired scalp EEG is associated with a higher risk of seizure recurrence and could be used as a prognostic marker. Methods 100 children presenting with new onset seizure to Children’s Medical Center- Dallas during 2015–2016, who were not on ASM and had focal EDs on an awake and sleep EEG recorded with sample frequency of 500 HZ, were randomly identified by database review. EEGs were analyzed blinded to the data of the patients. HFOs were visually identified using review parameters including expanded time base and adjusted filter settings. Results The average age of patients was 6.3 years (±4.35 SD). HFOs were visually identified in 19% of the studied patients with an inter-rater reliability of 99% for HFO negative discharges and 78% agreement for identification of HFOs. HFOs were identified more often in the younger age group; however, they were identified in 11% of patients >5 years old. They were more frequently associated with spikes than with sharp waves and more often with higher amplitude EDs. Patients with HFOs were more likely to have a recurrence of seizures in the year after the first seizure (P < 0.05) and to continue to have seizures after 2 years (P < 0.0001). There was no statistically significant difference between the two groups with regards to continuing ASM after 2 years. Conclusion Including analysis for HFOs in routine EEG interpretation may increase the yield of the study and help guide the decision to either start or discontinue ASM. In the future, this may also help to identify pathological discharges with deleterious effects on the growing brain and set a new target for the management of epilepsy.
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Affiliation(s)
- Hanan El Shakankiry
- UT Southwestern Medical School, Children's Health, Dallas, TX, United States
| | - Susan T Arnold
- UT Southwestern Medical School, Children's Health, Dallas, TX, United States
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16
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Wang W, Li H, Yan J, Zhang H, Li X, Zheng S, Wang J, Xing Y, Cheng L, Li D, Lai H, Qu J, Loh HH, Fang F, Yang X. Automatic detection of interictal ripples on scalp EEG to evaluate the effect and prognosis of ACTH therapy in patients with infantile spasms. Epilepsia 2021; 62:2240-2251. [PMID: 34309835 DOI: 10.1111/epi.17018] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 12/22/2022]
Abstract
OBJECTIVE We aimed to explore the feasibility of using scalp-recorded high-frequency oscillations (HFOs) to evaluate the efficacy and prognosis of adrenocorticotropic hormone (ACTH) treatment in patients with infantile spasms. METHODS Thirty-nine children with infantile spasms were enrolled and divided into seizure-free and non-seizure-free groups after ACTH treatment. Patients who were seizure-free were further divided into relapse and non-relapse subgroups based on the observations made during a 6-month follow-up period. Scalp ripples were detected and compared during the interictal periods before and after 2 weeks of treatment. RESULTS After ACTH treatment, the number and channels of ripples were significantly lower, whereas the percentage decrease in the number, spectral power, and channels of ripples was significantly higher in the seizure-free group than in the non-seizure-free group. In addition, the relapse subgroup showed higher number and spectral power and wider distribution of ripples than did the non-relapse subgroup. Changes in HFOs in terms of number, spectral power, and channel of ripples were closely related to the severity of epilepsy and can indicate disease susceptibility. SIGNIFICANCE Scalp HFOs can be used as an effective biomarker to monitor the effect and evaluate the prognosis of ACTH therapy in patients with infantile spasms.
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Affiliation(s)
- Wei Wang
- Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Hua Li
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Jiaqing Yan
- College of Electrical and Control Engineering, North China University of Technology, Beijing, China
| | - Herui Zhang
- Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Xiaonan Li
- Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Su Zheng
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Jiaoyang Wang
- Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Yue Xing
- Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Lipeng Cheng
- Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Donghong Li
- The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Huanling Lai
- Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Junda Qu
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, School of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Horace H Loh
- Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
| | - Fang Fang
- Department of Neurology, National Center for Children's Health, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Xiaofeng Yang
- Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China.,Bioland Laboratory Guangzhou Regenerative Medicine and Health Guangdong Laboratory, Guangzhou, China
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17
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Kumar U, Li L, Bragin A, Engel J. Spike and wave discharges and fast ripples during posttraumatic epileptogenesis. Epilepsia 2021; 62:1842-1851. [PMID: 34155626 DOI: 10.1111/epi.16958] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 05/20/2021] [Accepted: 05/23/2021] [Indexed: 12/28/2022]
Abstract
OBJECTIVE The goal of the present study was to determine whether spike and wave discharges (SWDs) and SWDs with superimposed fast ripples (SWDFRs) could be biomarkers of posttraumatic epileptogenesis. METHODS Fluid percussion injury was conducted on 13-14-week old male Sprague Dawley rats. Immediately after traumatic brain injury (TBI), they were implanted with microelectrodes in the neocortex, hippocampus, and striatum bilaterally. Age-matched sham rats with the same electrode implantation montage acted as controls. Wideband brain electrical activity was recorded intermittently from Day 1 of TBI, and continued from 2 to 21 weeks after TBI. SWD and SWDFR analysis was performed during the first 2 weeks to investigate whether the occurrence of this pattern predicted development of epilepsy. The remaining 3-21 weeks were used for identifying which rats became epileptic (E+ group) and which did not (E- group). RESULTS The E+ group (n = 9) showed a significant increase in SWD rate in prefrontal cortex during Weeks 1 and 2 after TBI. The E- group showed a significant increase in SWD rate only in the second week. One hundred percent of rats in the E+ group displayed SWDFRs beginning from the first week after TBI. The SWDFR pattern was observed in all recorded brain areas: prefrontal and perilesional cortices, hippocampus, and striatum. None of rats in the E- group showed coexistence of fast ripples with SWDs. SIGNIFICANCE Occurrence of SWDFRs after TBI, but not an increase in the rate of SWDs, could be a noninvasive electroencephalographic biomarker of posttraumatic epileptogenesis.
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Affiliation(s)
- Udaya Kumar
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA
| | - Lin Li
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA.,Department of Biomedical Engineering, University of North Texas, Denton, Texas, USA
| | - Anatol Bragin
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA.,Brain Research Institute, University of California, Los Angeles, Los Angeles, California, USA
| | - Jerome Engel
- Department of Neurology, University of California, Los Angeles, Los Angeles, California, USA.,Brain Research Institute, University of California, Los Angeles, Los Angeles, California, USA.,Department of Neurobiology and Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, California, USA
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18
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Kobayashi K, Shibata T, Tsuchiya H, Akiyama T. Exclusion of the Possibility of "False Ripples" From Ripple Band High-Frequency Oscillations Recorded From Scalp Electroencephalogram in Children With Epilepsy. Front Hum Neurosci 2021; 15:696882. [PMID: 34211382 PMCID: PMC8239160 DOI: 10.3389/fnhum.2021.696882] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 05/24/2021] [Indexed: 11/24/2022] Open
Abstract
Aim Ripple-band epileptic high-frequency oscillations (HFOs) can be recorded by scalp electroencephalography (EEG), and tend to be associated with epileptic spikes. However, there is a concern that the filtration of steep waveforms such as spikes may cause spurious oscillations or “false ripples.” We excluded such possibility from at least some ripples by EEG differentiation, which, in theory, enhances high-frequency signals and does not generate spurious oscillations or ringing. Methods The subjects were 50 pediatric patients, and ten consecutive spikes during sleep were selected for each patient. Five hundred spike data segments were initially reviewed by two experienced electroencephalographers using consensus to identify the presence or absence of ripples in the ordinary filtered EEG and an associated spectral blob in time-frequency analysis (Session A). These EEG data were subjected to numerical differentiation (the second derivative was denoted as EEG″). The EEG″ trace of each spike data segment was shown to two other electroencephalographers who judged independently whether there were clear ripple oscillations or uncertain ripple oscillations or an absence of oscillations (Session B). Results In Session A, ripples were identified in 57 spike data segments (Group A-R), but not in the other 443 data segments (Group A-N). In Session B, both reviewers identified clear ripples (strict criterion) in 11 spike data segments, all of which were in Group A-R (p < 0.0001 by Fisher’s exact test). When the extended criterion that included clear and/or uncertain ripples was used in Session B, both reviewers identified 25 spike data segments that fulfilled the criterion: 24 of these were in Group A-R (p < 0.0001). Discussion We have demonstrated that real ripples over scalp spikes exist in a certain proportion of patients. Ripples that were visualized consistently using both ordinary filters and the EEG″ method should be true, but failure to clarify ripples using the EEG″ method does not mean that true ripples are absent. Conclusion The numerical differentiation of EEG data provides convincing evidence that HFOs were detected in terms of the presence of such unusually fast oscillations over the scalp and the importance of this electrophysiological phenomenon.
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Affiliation(s)
- Katsuhiro Kobayashi
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Takashi Shibata
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Hiroki Tsuchiya
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Tomoyuki Akiyama
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
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Cserpan D, Boran E, Lo Biundo SP, Rosch R, Sarnthein J, Ramantani G. Scalp high-frequency oscillation rates are higher in younger children. Brain Commun 2021; 3:fcab052. [PMID: 33870193 PMCID: PMC8042248 DOI: 10.1093/braincomms/fcab052] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/30/2021] [Accepted: 02/15/2021] [Indexed: 12/15/2022] Open
Abstract
High-frequency oscillations in scalp EEG are promising non-invasive biomarkers of epileptogenicity. However, it is unclear how high-frequency oscillations are impacted by age in the paediatric population. We prospectively recorded whole-night scalp EEG in 30 children and adolescents with focal or generalized epilepsy. We used an automated and clinically validated high-frequency oscillation detector to determine ripple rates (80-250 Hz) in bipolar channels. Children < 7 years had higher high-frequency oscillation rates (P = 0.021) when compared with older children. The median test-retest reliability of high-frequency oscillation rates reached 100% (iqr 50) for a data interval duration of 10 min. Scalp high-frequency oscillation frequency decreased with age (r = -0.558, P = 0.002), whereas scalp high-frequency oscillation duration and amplitude were unaffected. The signal-to-noise ratio improved with age (r = 0.37, P = 0.048), and the background ripple band activity decreased with age (r = -0.463, P = 0.011). We characterize the relationship of scalp high-frequency oscillation features and age in paediatric patients. EEG intervals of ≥ 10 min duration are required for reliable measurements of high-frequency oscillation rates. This study is a further step towards establishing scalp high-frequency oscillations as a valid epileptogenicity biomarker in this vulnerable age group.
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Affiliation(s)
- Dorottya Cserpan
- Department of Neuropediatrics, University Children's Hospital Zurich, 8032 Zurich, Switzerland,Department of Neurosurgery, University Hospital Zurich, 8006 Zurich, Switzerland
| | - Ece Boran
- Department of Neurosurgery, University Hospital Zurich, 8006 Zurich, Switzerland
| | - Santo Pietro Lo Biundo
- Department of Neuropediatrics, University Children's Hospital Zurich, 8032 Zurich, Switzerland
| | - Richard Rosch
- Department of Neuropediatrics, University Children's Hospital Zurich, 8032 Zurich, Switzerland
| | - Johannes Sarnthein
- Department of Neurosurgery, University Hospital Zurich, 8006 Zurich, Switzerland,University of Zurich, 8006 Zurich, Switzerland,Klinisches Neurozentrum Zurich, University Hospital Zurich, 8006 Zurich, Switzerland
| | - Georgia Ramantani
- Department of Neuropediatrics, University Children's Hospital Zurich, 8032 Zurich, Switzerland,University of Zurich, 8006 Zurich, Switzerland,Children’s Research Centre, University Children's Hospital Zurich, 8032 Zurich, Switzerland,Correspondence to: Georgia Ramantani, MD, PhD Department of Neuropediatrics, University Children's Hospital Zurich Steinwiesstrasse 75, 8032 Zurich, Switzerland. E-mail:
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20
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Stoyell SM, Wilmskoetter J, Dobrota MA, Chinappen DM, Bonilha L, Mintz M, Brinkmann BH, Herman ST, Peters JM, Vulliemoz S, Seeck M, Hämäläinen MS, Chu CJ. High-Density EEG in Current Clinical Practice and Opportunities for the Future. J Clin Neurophysiol 2021; 38:112-123. [PMID: 33661787 PMCID: PMC8083969 DOI: 10.1097/wnp.0000000000000807] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
SUMMARY High-density EEG (HD-EEG) recordings use a higher spatial sampling of scalp electrodes than a standard 10-20 low-density EEG montage. Although several studies have demonstrated improved localization of the epileptogenic cortex using HD-EEG, widespread implementation is impeded by cost, setup and interpretation time, and lack of specific or sufficient procedural billing codes. Despite these barriers, HD-EEG has been in use at several institutions for years. These centers have noted utility in a variety of clinical scenarios where increased spatial resolution from HD-EEG has been required, justifying the extra time and cost. We share select scenarios from several centers, using different recording techniques and software, where HD-EEG provided information above and beyond the standard low-density EEG. We include seven cases where HD-EEG contributed directly to current clinical care of epilepsy patients and highlight two novel techniques which suggest potential opportunities to improve future clinical care. Cases illustrate how HD-EEG allows clinicians to: case 1-lateralize falsely generalized interictal epileptiform discharges; case 2-improve localization of falsely generalized epileptic spasms; cases 3 and 4-improve localization of interictal epileptiform discharges in anatomic regions below the circumferential limit of standard low-density EEG coverage; case 5-improve noninvasive localization of the seizure onset zone in lesional epilepsy; cases 6 and 7-improve localization of the seizure onset zone to guide invasive investigation near eloquent cortex; case 8-identify epileptic fast oscillations; and case 9-map language cortex. Together, these nine cases illustrate that using both visual analysis and advanced techniques, HD-EEG can play an important role in clinical management.
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Affiliation(s)
- Sally M Stoyell
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, U.S.A
| | - Janina Wilmskoetter
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina, U.S.A
| | - Mary-Ann Dobrota
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, U.S.A
| | | | - Leonardo Bonilha
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina, U.S.A
| | - Mark Mintz
- The Center for Neurological and Neurodevelopmental Health, Voorhees, New Jersey, U.S.A
| | | | - Susan T Herman
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, Massachusetts, U.S.A
| | - Jurriaan M Peters
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, U.S.A
| | - Serge Vulliemoz
- EEG and Epilepsy Unit, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Margitta Seeck
- EEG and Epilepsy Unit, University Hospitals and University of Geneva, Geneva, Switzerland
| | - Matti S Hämäläinen
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts, U.S.A
- Harvard Medical School, Boston, Massachusetts, U.S.A
| | - Catherine J Chu
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, U.S.A
- Harvard Medical School, Boston, Massachusetts, U.S.A
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21
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McCrimmon CM, Riba A, Garner C, Maser AL, Phillips DJ, Steenari M, Shrey DW, Lopour BA. Automated detection of ripple oscillations in long-term scalp EEG from patients with infantile spasms. J Neural Eng 2021; 18. [PMID: 33217752 DOI: 10.1088/1741-2552/abcc7e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 11/20/2020] [Indexed: 11/11/2022]
Abstract
Objective.Scalp high-frequency oscillations (HFOs) are a promising biomarker of epileptogenicity in infantile spasms (IS) and many other epilepsy syndromes, but prior studies have relied on visual analysis of short segments of data due to the prevalence of artifacts in EEG. Here we set out to robustly characterize the rate and spatial distribution of HFOs in large datasets from IS subjects using fully automated HFO detection techniques.Approach.We prospectively collected long-term scalp EEG data from 12 subjects with IS and 18 healthy controls. For patients with IS, recording began prior to diagnosis and continued through initiation of treatment with adrenocorticotropic hormone (ACTH). The median analyzable EEG duration was 18.2 h for controls and 84.5 h for IS subjects (∼1300 h total). Ripples (80-250 Hz) were detected in all EEG data using an automated algorithm.Main results.HFO rates were substantially higher in patients with IS compared to controls. In IS patients, HFO rates were higher during sleep compared to wakefulness (median 5.5 min-1and 2.9 min-1, respectively;p = 0.002); controls did not exhibit a difference in HFO rate between sleep and wakefulness (median 0.98 min-1and 0.82 min-1, respectively). Spatially, IS patients exhibited significantly higher rates of HFOs in the posterior parasaggital region and significantly lower HFO rates in frontal channels, and this difference was more pronounced during sleep. In IS subjects, ACTH therapy significantly decreased the rate of HFOs.Significance.Here we provide a detailed characterization of the spatial distribution and rates of HFOs associated with IS, which may have relevance for diagnosis and assessment of treatment response. We also demonstrate that our fully automated algorithm can be used to detect HFOs in long-term scalp EEG with sufficient accuracy to clearly discriminate healthy subjects from those with IS.
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Affiliation(s)
- Colin M McCrimmon
- Medical Scientist Training Program, University of California, Irvine, CA 92617, United States of America.,Department Neurology, University of California, Los Angeles, CA 90095, United States of America
| | - Aliza Riba
- Division Neurology, Children's Hospital of Orange County, Orange, CA 92868, United States of America
| | - Cristal Garner
- Division Neurology, Children's Hospital of Orange County, Orange, CA 92868, United States of America
| | - Amy L Maser
- Department Psychology, Children's Hospital of Orange County, Orange, CA 92868, United States of America
| | - Donald J Phillips
- Division Neurology, Children's Hospital of Orange County, Orange, CA 92868, United States of America.,Department Pediatrics, University of California, Irvine, Irvine, CA 92617, United States of America
| | - Maija Steenari
- Division Neurology, Children's Hospital of Orange County, Orange, CA 92868, United States of America.,Department Pediatrics, University of California, Irvine, Irvine, CA 92617, United States of America
| | - Daniel W Shrey
- Division Neurology, Children's Hospital of Orange County, Orange, CA 92868, United States of America.,Department Pediatrics, University of California, Irvine, Irvine, CA 92617, United States of America
| | - Beth A Lopour
- Department Biomedical Engineering, University of California, Irvine, Irvine, CA 92617, United States of America
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22
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Fan Y, Dong L, Liu X, Wang H, Liu Y. Recent advances in the noninvasive detection of high-frequency oscillations in the human brain. Rev Neurosci 2020; 32:305-321. [PMID: 33661582 DOI: 10.1515/revneuro-2020-0073] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/23/2020] [Indexed: 01/10/2023]
Abstract
In recent decades, a significant body of evidence based on invasive clinical research has showed that high-frequency oscillations (HFOs) are a promising biomarker for localization of the seizure onset zone (SOZ), and therefore, have the potential to improve postsurgical outcomes in patients with epilepsy. Emerging clinical literature has demonstrated that HFOs can be recorded noninvasively using methods such as scalp electroencephalography (EEG) and magnetoencephalography (MEG). Not only are HFOs considered to be a useful biomarker of the SOZ, they also have the potential to gauge disease severity, monitor treatment, and evaluate prognostic outcomes. In this article, we review recent clinical research on noninvasively detected HFOs in the human brain, with a focus on epilepsy. Noninvasively detected scalp HFOs have been investigated in various types of epilepsy. HFOs have also been studied noninvasively in other pathologic brain disorders, such as migraine and autism. Herein, we discuss the challenges reported in noninvasive HFO studies, including the scarcity of MEG and high-density EEG equipment in clinical settings, low signal-to-noise ratio, lack of clinically approved automated detection methods, and the difficulty in differentiating between physiologic and pathologic HFOs. Additional studies on noninvasive recording methods for HFOs are needed, especially prospective multicenter studies. Further research is fundamental, and extensive work is needed before HFOs can routinely be assessed in clinical settings; however, the future appears promising.
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Affiliation(s)
- Yuying Fan
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Liping Dong
- Library of China Medical University, Shenyang, China
| | - Xueyan Liu
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Hua Wang
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yunhui Liu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
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23
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Fast oscillations >40 Hz localize the epileptogenic zone: An electrical source imaging study using high-density electroencephalography. Clin Neurophysiol 2020; 132:568-580. [PMID: 33450578 DOI: 10.1016/j.clinph.2020.11.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 10/04/2020] [Accepted: 11/06/2020] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Fast Oscillations (FO) >40 Hz are a promising biomarker of the epileptogenic zone (EZ). Evidence using scalp electroencephalography (EEG) remains scarce. We assessed if electrical source imaging of FO using 256-channel high-density EEG (HD-EEG) is useful for EZ identification. METHODS We analyzed HD-EEG recordings of 10 focal drug-resistant epilepsy patients with seizure-free postsurgical outcome. We marked FO candidate events at the time of epileptic spikes and verified them by screening for an isolated peak in the time-frequency plot. We performed electrical source imaging of spikes and FO within the Maximum Entropy of the Mean framework. Source localization maps were validated against the surgical cavity. RESULTS We identified FO in five out of 10 patients who had a superficial or intermediate deep generator. The maximum of the FO maps was localized inside the cavity in all patients (100%). Analysis with a reduced electrode coverage using the 10-10 and 10-20 system showed a decreased localization accuracy of 60% and 40% respectively. CONCLUSIONS FO recorded with HD-EEG localize the EZ. HD-EEG is better suited to detect and localize FO than conventional EEG approaches. SIGNIFICANCE This study acts as proof-of-concept that FO localization using 256-channel HD-EEG is a viable marker of the EZ.
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Klotz KA, Sag Y, Schönberger J, Jacobs J. Scalp Ripples Can Predict Development of Epilepsy After First Unprovoked Seizure in Childhood. Ann Neurol 2020; 89:134-142. [PMID: 33070359 DOI: 10.1002/ana.25939] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 01/14/2023]
Abstract
OBJECTIVE Identification of children at risk of developing epilepsy after a first unprovoked seizure can be challenging. Interictal epileptiform discharges are associated with higher risk but have limited sensitivity and specificity. High frequency oscillations (HFOs) are newer biomarkers for epileptogenesis. We prospectively evaluated the predictive value of HFOs for developing epilepsy in scalp electroencephalogram (EEG) of children after a first unprovoked seizure. METHODS After their first seizure, 56 children were followed prospectively over 12 months and then grouped in "epilepsy" or "no epilepsy." Initial EEGs were visually analyzed for spikes, spike ripples, and ripples. Inter-group comparisons of spike-rates and HFO-rates were done by Mann-Whitney U test. Predictive values and optimal thresholds were calculated by receiver operating characteristic (ROC) curves. RESULTS In the epilepsy group (n = 26, 46%), mean rates of ripples (0.3 vs 0.09 / minute, p < 0.0001) and spike ripples (0.6 vs 0.06 / minute, p < 0.05) were significantly higher, with no difference in spike rates (1.7 vs 3.0 / minute, p = 0.38). Of those 3 markers, ripples showed the best predictive value (area under the curve [AUC]ripples = 0.88). The optimal threshold for ripples was calculated to be ≥ 0.125 / minute with a sensitivity of 87% and specificity of 85%. Ripple rates were negatively correlated to days passing before epilepsy-diagnosis (R = -0.59, p < 0.0001) and time to a second seizure (R = -0.64, 95% confidence interval [CI] = -0.77 to 0.43, p < 0.0001). INTERPRETATION We could show that in a cohort of children with a first unprovoked seizure, ripples predict the development of epilepsy better than spikes or spike ripples and might be useful biomarkers in the estimation of prognosis and question of treatment. ANN NEUROL 2021;89:134-142.
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Affiliation(s)
- Kerstin A Klotz
- Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Yusuf Sag
- Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jan Schönberger
- Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Berta-Ottenstein-Programme, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Julia Jacobs
- Department of Neuropediatrics and Muscle Disorders, Center for Pediatrics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Section of Pediatric Neurology, Alberta Children's Hospital, University of Calgary, Calgary, AB, Canada
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Jacobs J, Zijlmans M. HFO to Measure Seizure Propensity and Improve Prognostication in Patients With Epilepsy. Epilepsy Curr 2020; 20:338-347. [PMID: 33081501 PMCID: PMC7818207 DOI: 10.1177/1535759720957308] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The study of high frequency oscillations (HFO) in the electroencephalogram (EEG)
as biomarkers of epileptic activity has merely focused on their spatial location
and relationship to the epileptogenic zone. It has been suggested in several
ways that the amount of HFO at a certain point in time may reflect the disease
activity or severity. This could be clinically useful in several ways,
especially as noninvasive recording of HFO appears feasible. We grouped the
potential hypotheses into 4 categories: (1) HFO as biomarkers to predict the
development of epilepsy; (2) HFO as biomarkers to predict the occurrence of
seizures; (3) HFO as biomarkers linked to the severity of epilepsy, and (4) HFO
as biomarkers to evaluate outcome of treatment. We will review the literature
that addresses these 4 hypotheses and see to what extent HFO can be used to
measure seizure propensity and help determine prognosis of this unpredictable
disease.
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Affiliation(s)
- Julia Jacobs
- 157744Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
| | - Maeike Zijlmans
- 36512UMC Utrecht Brain Center Rudolf Magnus, Utrecht, the Netherlands
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Tsuchiya H, Endoh F, Akiyama T, Matsuhashi M, Kobayashi K. Longitudinal correspondence of epilepsy and scalp EEG fast (40-200 Hz) oscillations in pediatric patients with tuberous sclerosis complex. Brain Dev 2020; 42:663-674. [PMID: 32631641 DOI: 10.1016/j.braindev.2020.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 05/29/2020] [Accepted: 06/03/2020] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Epilepsy associated with tuberous sclerosis complex (TSC) has very complex clinical characteristics. Scalp electroencephalogram (EEG) fast (40-200 Hz) oscillations (FOs) were recently suggested to indicate epilepsy severity. Epileptic FOs may undergo age-dependent longitudinal change in individual patients, however, and the typical pattern of such change is not yet fully clarified. We therefore investigated the age-related correspondence between clinical courses and FOs in pediatric patients with TSC-associated epilepsy. SUBJECTS AND METHODS FOs were semi-automatically detected from scalp sleep EEG data recorded from 23 children (15 boys, 8 girls; initial data obtained at <10 years of age) with TSC-associated epilepsy. RESULTS The number of FOs per patient that were associated with spikes was significantly greater than that of FOs unassociated with spikes (median 145 and 5, respectively; p = 0.0001 by the Wilcoxon signed-rank test). In the eight patients who had West syndrome (WS) in infancy, FOs associated with spikes were abundant during the WS period prior to adrenocorticotropic hormone therapy, with significantly greater numbers of FOs compared to the post-WS period (median 242 and 0, respectively; p = 0.0078). As there was no such time-dependent difference regarding FOs unassociated with spikes, FOs associated with spikes were identified as epileptic. The detected FOs included both gamma and ripple oscillations with no consistent age-dependent shifts in dominant frequency. There were no apparent age-related changes in FO duration. CONCLUSIONS Epileptic scalp FOs are confirmed to correspond to severity of epileptic encephalopathy, particularly in WS, even during the long-term evolutional courses of TSC-associated epilepsy.
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Affiliation(s)
- Hiroki Tsuchiya
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan.
| | - Fumika Endoh
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan; Department of Child Neurology, NHO Minami-Okayama Medical Center, Okayama, Okayama, Japan
| | - Tomoyuki Akiyama
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
| | - Masao Matsuhashi
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Katsuhiro Kobayashi
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital, Okayama, Japan
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Nariai H, Hussain SA, Bernardo D, Motoi H, Sonoda M, Kuroda N, Asano E, Nguyen JC, Elashoff D, Sankar R, Bragin A, Staba RJ, Wu JY. Scalp EEG interictal high frequency oscillations as an objective biomarker of infantile spasms. Clin Neurophysiol 2020; 131:2527-2536. [PMID: 32927206 DOI: 10.1016/j.clinph.2020.08.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/25/2020] [Accepted: 08/04/2020] [Indexed: 12/21/2022]
Abstract
OBJECTIVE To investigate the diagnostic utility of high frequency oscillations (HFOs) via scalp electroencephalogram (EEG) in infantile spasms. METHODS We retrospectively analyzed interictal slow-wave sleep EEGs sampled at 2,000 Hz recorded from 30 consecutive patients who were suspected of having infantile spasms. We measured the rate of HFOs (80-500 Hz) and the strength of the cross-frequency coupling between HFOs and slow-wave activity (SWA) at 3-4 Hz and 0.5-1 Hz as quantified with modulation indices (MIs). RESULTS Twenty-three patients (77%) exhibited active spasms during the overnight EEG recording. Although the HFOs were detected in all children, increased HFO rate and MIs correlated with the presence of active spasms (p < 0.001 by HFO rate; p < 0.01 by MIs at 3-4 Hz; p = 0.02 by MIs at 0.5-1 Hz). The presence of active spasms was predicted by the logistic regression models incorporating HFO-related metrics (AUC: 0.80-0.98) better than that incorporating hypsarrhythmia (AUC: 0.61). The predictive performance of the best model remained favorable (87.5% accuracy) after a cross-validation procedure. CONCLUSIONS Increased rate of HFOs and coupling between HFOs and SWA are associated with active epileptic spasms. SIGNIFICANCE Scalp-recorded HFOs may serve as an objective EEG biomarker for active epileptic spasms.
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Affiliation(s)
- Hiroki Nariai
- Division of Pediatric Neurology, Department of Pediatrics, UCLA Mattel Children's Hospital, David Geffen School of Medicine, Los Angeles, California, USA.
| | - Shaun A Hussain
- Division of Pediatric Neurology, Department of Pediatrics, UCLA Mattel Children's Hospital, David Geffen School of Medicine, Los Angeles, California, USA
| | - Danilo Bernardo
- Department of Neurology, Division of Epilepsy, University of California, San Francisco, San Francisco, CA, USA
| | - Hirotaka Motoi
- Department of Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Masaki Sonoda
- Department of Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Naoto Kuroda
- Department of Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Eishi Asano
- Department of Pediatrics and Neurology, Children's Hospital of Michigan, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Jimmy C Nguyen
- Division of Pediatric Neurology, Department of Pediatrics, UCLA Mattel Children's Hospital, David Geffen School of Medicine, Los Angeles, California, USA
| | - David Elashoff
- Department of Medicine, Statistics Core, University of California, Los Angeles, Los Angeles, California, USA
| | - Raman Sankar
- Division of Pediatric Neurology, Department of Pediatrics, UCLA Mattel Children's Hospital, David Geffen School of Medicine, Los Angeles, California, USA
| | - Anatol Bragin
- Department of Neurology, UCLA Medical Center, David Geffen School of Medicine, Los Angeles, California, USA
| | - Richard J Staba
- Department of Neurology, UCLA Medical Center, David Geffen School of Medicine, Los Angeles, California, USA
| | - Joyce Y Wu
- Division of Pediatric Neurology, Department of Pediatrics, UCLA Mattel Children's Hospital, David Geffen School of Medicine, Los Angeles, California, USA
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Abstract
We aimed to explore the link between NREM sleep and epilepsy. Based on human and experimental data we propose that a sleep-related epileptic transformation of normal neurological networks underlies epileptogenesis. Major childhood epilepsies as medial temporal lobe epilepsy (MTLE), absence epilepsy (AE) and human perisylvian network (PN) epilepsies - made us good models to study. These conditions come from an epileptic transformation of the affected functional systems. This approach allows a system-based taxonomy instead of the outworn generalized-focal classification. MTLE links to the memory-system, where epileptic transformation results in a switch of normal sharp wave-ripples to epileptic spikes and pathological high frequency oscillations, compromising sleep-related memory consolidation. Absence epilepsy (AE) and juvenile myoclonic epilepsy (JME) belong to the corticothalamic system. The burst-firing mode of NREM sleep normally producing sleep-spindles turns to an epileptic working mode ejecting bilateral synchronous spike-waves. There seems to be a progressive transition from AE to JME. Shared absences and similar bilateral synchronous discharges show the belonging of the two conditions, while the continuous age windows - AE affecting schoolchildren, JME the adolescents - and the increased excitability in JME compared to AE supports the notion of progression. In perisylvian network epilepsies - idiopathic focal childhood epilepsies and electrical status epilepticus in sleep including Landau-Kleffner syndrome - centrotemporal spikes turn epileptic, with the potential to cause cognitive impairment. Postinjury epilepsies modeled by the isolated cortex model highlight the shared way of epileptogenesis suggesting the derailment of NREM sleep-related homeostatic plasticity as a common step. NREM sleep provides templates for plasticity derailing to epileptic variants under proper conditions. This sleep-origin explains epileptiform discharges' link and similarity with NREM sleep slow oscillations, spindles and ripples. Normal synaptic plasticity erroneously overgrowing homeostatic processes may derail toward an epileptic working-mode manifesting the involved system's features. The impact of NREM sleep is unclear in epileptogenesis occurring in adolescence and adulthood, when plasticity is lower. The epileptic process interferes with homeostatic synaptic plasticity and may cause cognitive impairment. Its type and degree depends on the affected network's function. We hypothesize a vicious circle between sleep end epilepsy. The epileptic derailment of normal plasticity interferes with sleep cognitive functions. Sleep and epilepsy interconnect by the pathology of plasticity.
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Affiliation(s)
- Péter Halász
- Szentágothai János School of Ph.D Studies, Clinical Neurosciences, Semmelweis University, Budapest, Hungary
| | - Anna Szűcs
- Institute of Behavioral Sciences, Semmelweis University, Budapest, Hungary
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Electroencephalographic abnormalities are correlated with cognitive deficits in children with benign childhood epilepsy with centrotemporal spikes: A clinical study of 61 cases. Epilepsy Behav 2020; 106:107012. [PMID: 32179505 DOI: 10.1016/j.yebeh.2020.107012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 02/24/2020] [Accepted: 02/28/2020] [Indexed: 02/08/2023]
Abstract
OBJECTIVE The objective of this study was to explore the effect of spikes on cognition in patients with benign childhood epilepsy with centrotemporal spikes (BECTS) and to identify electroencephalography (EEG) markers enabling early detection of cognitive impairment. METHODS Sixty-one children with BECTS diagnoses and 60 age- and education-matched healthy controls were enrolled. Four-hour EEG recordings were analyzed for each patient to check for interictal spikes, high-frequency oscillations (HFOs), nondipole spikes, and other atypical EEG features and to examine the spike-wave index of nonrapid eye movement (NREM) sleep. All 121 children underwent a series of neuropsychological tests to assess cognitive function. RESULTS Patients with a high NREM sleep discharge index (≥55%) in the first sleep cycle exhibited significantly lower scores for arithmetic calculation, executive function, and attention and memory tests than patients with a low discharge index (<55%). Eight patients with HFOs exhibited even poorer performance than HFO-negative patients for arithmetic calculation, executive function, vocabulary comprehension, visual perception, vocal perception, spatial memory ability, and response ability. Children with bilateral discharge exhibited poorer ability in three-dimensional spatial imaging test, poorer memory, and slower response than did those with unilateral discharge (P < .05). Nondipole spikes, multiple asynchronous discharges, and generalized spike-wave discharges respectively had an impact on calculation ability, memory, and reaction ability respectively (P < .05). CONCLUSIONS Spike frequencies in stage 3 and 4 sleep varied from those observed in stage 1 and 2 sleep; the highest spike frequency was in stage 2 sleep. High NREM sleep discharge index (i.e., ≥55%) and HFOs were linked to the highest risk for cognitive deficit, while bilateral discharges, nondipole spikes, multiple asynchronous discharges, and generalized spike-wave discharges were less indicative of cognitive impairment.
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30
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High-frequency oscillations in a spectrum of pediatric epilepsies characterized by sleep-activated spikes in scalp EEG. Clin Neurophysiol 2019; 130:1971-1980. [DOI: 10.1016/j.clinph.2019.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 08/04/2019] [Accepted: 08/12/2019] [Indexed: 12/16/2022]
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Cao D, Chen Y, Liao J, Nariai H, Li L, Zhu Y, Zhao X, Hu Y, Wen F, Zhai Q. Scalp EEG high frequency oscillations as a biomarker of treatment response in epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS). Seizure 2019; 71:151-157. [PMID: 31351306 DOI: 10.1016/j.seizure.2019.05.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 04/28/2019] [Accepted: 05/29/2019] [Indexed: 02/08/2023] Open
Abstract
PURPOSE We investigated whether the presence of interictal scalp EEG high frequency oscillations (HFOs) in children with epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) can predict seizure and cognitive outcome after steroid therapy. METHODS Twenty-two children with CSWS were prospectively enrolled and received methylprednisolone therapy. Interictal scalp HFOs, spike wave index (SWI) and intelligence quotient (IQ) were assessed before and after the treatment. The children were divided into two groups based on the early seizure reduction ratio at 2 weeks (≥50%, "response group"; otherwise "non-response group"). The "response group" was further divided into two subgroups ("relapse" and "non-relapse" subgroups) according to the late seizure outcome (after 3 months). RESULTS Interictal HFOs and electrical status epilepticus in sleep (ESES) (defined as SWI ≥ 85%) were detected in all children at the baseline. In the response with relapse group (n = 11), the detection ratio of HFOs was significantly higher than that of ESES at 2 weeks (81.2 vs. 27.3%), 3 months (90.9 vs. 36.4%), and 6 months (100 vs. 54.5%) post-therapy. In the non-response group (n = 4), both HFOs and ESES persisted in all children. The average IQ improved significantly only in the response with non-relapse group. The persistence of HFOs negatively correlated with both the average IQ, yet the persistence of ESES did not. CONCLUSION Interictal scalp HFOs may be a favorable non-invasive biomarker of predicting seizure and cognitive outcome in CSWS.
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Affiliation(s)
- Dezhi Cao
- Second Clinical Medical College, Southern Medical University, Guangzhou, Guangdong, China; Neurology Department, Shenzhen Children's Hospital, Guangdong, China; Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Yan Chen
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Jianxiang Liao
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Hiroki Nariai
- Division of Pediatric Neurology, UCLA Mattel Children's Hospital, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Lin Li
- Department of Neurology, University of California Los Angeles, Los Angeles, CA, USA
| | - Yanwei Zhu
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Xia Zhao
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Yan Hu
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Feiqiu Wen
- Neurology Department, Shenzhen Children's Hospital, Guangdong, China
| | - Qiongxiang Zhai
- Second Clinical Medical College, Southern Medical University, Guangzhou, Guangdong, China; Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China.
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Bourel-Ponchel E, Mahmoudzadeh M, Adebimpe A, Wallois F. Functional and Structural Network Disorganizations in Typical Epilepsy With Centro-Temporal Spikes and Impact on Cognitive Neurodevelopment. Front Neurol 2019; 10:809. [PMID: 31555191 PMCID: PMC6727184 DOI: 10.3389/fneur.2019.00809] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 07/15/2019] [Indexed: 12/20/2022] Open
Abstract
Epilepsy with Centrotemporal Spikes (ECTS) is the most common form of self-limited focal epilepsy. The pathophysiological mechanisms by which ECTS induces neuropsychological impairment in 15-30% of affected children remain unclear. The objective of this study is to review the current state of knowledge concerning the brain structural and functional changes that may be involved in cognitive dysfunctions in ECTS. Structural brain imaging suggests the presence of subtle neurodevelopmental changes over the epileptogenic zone and over distant regions in ECTS. This structural remodeling likely occurs prior to the diagnosis and evolves over time, especially in patients with cognitive impairment, suggesting that the epileptogenic processes might interfere with the dynamics of the brain development and/or the normal maturation processes. Functional brain imaging demonstrates profound disorganization accentuated by interictal epileptic spikes (IES) in the epileptogenic zone and in remote networks in ECTS. Over the epileptogenic zone, the literature demonstrates changes in term of neuronal activity and synchronization, which are effective several hundred milliseconds before the IES. In the same time window, functional changes are also observed in bilateral distant networks, notably in the frontal and temporal lobes. Effective connectivity demonstrates that the epileptogenic zone constitutes the key area at the origin of IES propagation toward distant cortical regions, including frontal areas. Altogether, structural and functional network disorganizations, in terms of: (i) power spectral values, (ii) functional and effective connectivity, are likely to participate in the cognitive impairment commonly reported in children with ECTS. These results suggest a central and causal role of network disorganizations related to IES in the neuropsychological impairment described in ECTS children.
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Affiliation(s)
- Emilie Bourel-Ponchel
- INSERM UMR 1105, Research Group on Multimodal Analysis of Brain Function, University of Picardie Jules Verne, Amiens, France
- INSERM UMR 1105, EFSN Pediatric, Amiens University Hospital, Amiens, France
| | - Mahdi Mahmoudzadeh
- INSERM UMR 1105, Research Group on Multimodal Analysis of Brain Function, University of Picardie Jules Verne, Amiens, France
- INSERM UMR 1105, EFSN Pediatric, Amiens University Hospital, Amiens, France
| | - Azeez Adebimpe
- INSERM UMR 1105, Research Group on Multimodal Analysis of Brain Function, University of Picardie Jules Verne, Amiens, France
| | - Fabrice Wallois
- INSERM UMR 1105, Research Group on Multimodal Analysis of Brain Function, University of Picardie Jules Verne, Amiens, France
- INSERM UMR 1105, EFSN Pediatric, Amiens University Hospital, Amiens, France
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Kramer MA, Ostrowski LM, Song DY, Thorn EL, Stoyell SM, Parnes M, Chinappen D, Xiao G, Eden UT, Staley KJ, Stufflebeam SM, Chu CJ. Scalp recorded spike ripples predict seizure risk in childhood epilepsy better than spikes. Brain 2019; 142:1296-1309. [PMID: 30907404 PMCID: PMC6487332 DOI: 10.1093/brain/awz059] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 01/09/2019] [Accepted: 01/21/2019] [Indexed: 11/12/2022] Open
Abstract
In the past decade, brief bursts of fast oscillations in the ripple range have been identified in the scalp EEG as a promising non-invasive biomarker for epilepsy. However, investigation and clinical application of this biomarker have been limited because standard approaches to identify these brief, low amplitude events are difficult, time consuming, and subjective. Recent studies have demonstrated that ripples co-occurring with epileptiform discharges ('spike ripple events') are easier to detect than ripples alone and have greater pathological significance. Here, we used objective techniques to quantify spike ripples and test whether this biomarker predicts seizure risk in childhood epilepsy. We evaluated spike ripples in scalp EEG recordings from a prospective cohort of children with a self-limited epilepsy syndrome, benign epilepsy with centrotemporal spikes, and healthy control children. We compared the rate of spike ripples between children with epilepsy and healthy controls, and between children with epilepsy during periods of active disease (active, within 1 year of seizure) and after a period of sustained seizure-freedom (seizure-free, >1 year without seizure), using semi-automated and automated detection techniques. Spike ripple rate was higher in subjects with active epilepsy compared to healthy controls (P = 0.0018) or subjects with epilepsy who were seizure-free ON or OFF medication (P = 0.0018). Among epilepsy subjects with spike ripples, each month seizure-free decreased the odds of a spike ripple by a factor of 0.66 [95% confidence interval (0.47, 0.91), P = 0.021]. Comparing the diagnostic accuracy of the presence of at least one spike ripple versus a classic spike event to identify group, we found comparable sensitivity and negative predictive value, but greater specificity and positive predictive value of spike ripples compared to spikes (P = 0.016 and P = 0.006, respectively). We found qualitatively consistent results using a fully automated spike ripple detector, including comparison with an automated spike detector. We conclude that scalp spike ripple events identify disease and track with seizure risk in this epilepsy population, using both semi-automated and fully automated detection methods, and that this biomarker outperforms analysis of spikes alone in categorizing seizure risk. These data provide evidence that spike ripples are a specific non-invasive biomarker for seizure risk in benign epilepsy with centrotemporal spikes and support future work to evaluate the utility of this biomarker to guide medication trials and tapers in these children and predict seizure risk in other at-risk populations.
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Affiliation(s)
- Mark A Kramer
- Boston University, Department of Mathematics and Statistics, Boston, MA, USA
| | - Lauren M Ostrowski
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | - Daniel Y Song
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | - Emily L Thorn
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | - Sally M Stoyell
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | - McKenna Parnes
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | | | - Grace Xiao
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
| | - Uri T Eden
- Boston University, Department of Mathematics and Statistics, Boston, MA, USA
| | - Kevin J Staley
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Steven M Stufflebeam
- Harvard Medical School, Boston, MA, USA
- Massachusetts General Hospital, Department of Radiology, Boston, MA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA
| | - Catherine J Chu
- Massachusetts General Hospital, Department of Neurology, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
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Song DY, Stoyell SM, Ross EE, Ostrowski LM, Thorn EL, Stufflebeam SM, Morgan AK, Emerton BC, Kramer MA, Chu CJ. Beta oscillations in the sensorimotor cortex correlate with disease and remission in benign epilepsy with centrotemporal spikes. Brain Behav 2019; 9:e01237. [PMID: 30790472 PMCID: PMC6422718 DOI: 10.1002/brb3.1237] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 01/14/2019] [Accepted: 01/16/2019] [Indexed: 12/27/2022] Open
Abstract
INTRODUCTION Benign epilepsy with centrotemporal spikes (BECTS) is a common form of childhood epilepsy with the majority of those afflicted remitting during their early teenage years. Seizures arise from the lower half of the sensorimotor cortex of the brain (e.g. seizure onset zone) and the abnormal epileptiform discharges observed increase during NREM sleep. To date no clinical factors reliably predict disease course, making determination of ongoing seizure risk a significant challenge. Prior work in BECTS have shown abnormalities in beta band (14.9-30 Hz) oscillations during movement and rest. Oscillations in this frequency band are modulated by state of consciousness and thought to reflect intrinsic inhibitory mechanisms. METHODS We used high density EEG and source localization techniques to examine beta band activity in the seizure onset zone (sensorimotor cortex) in a prospective cohort of children with BECTS and healthy controls during sleep. We hypothesized that beta power in the sensorimotor cortex would be different between patients and healthy controls, and that beta abnormalities would improve with resolution of disease in this self-limited epilepsy syndrome. We further explored the specificity of our findings and correlation with clinical features. Statistical testing was performed using logistic and standard linear regression models. RESULTS We found that beta band power in the seizure onset zone is different between healthy controls and BECTS patients. We also found that a longer duration of time spent seizure-free (corresponding to disease remission) correlates with lower beta power in the seizure onset zone. Exploratory spatial analysis suggests this effect is not restricted to the sensorimotor cortex. Exploratory frequency analysis suggests that this phenomenon is also observed in alpha and gamma range activity. We found no relationship between beta power and the presence or rate of epileptiform discharges in the sensorimotor cortex or a test of sensorimotor performance. CONCLUSION These results provide evidence that cortical beta power in the seizure onset zone may provide a dynamic physiological biomarker of disease in BECTS.
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Affiliation(s)
- Dan Y Song
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Sally M Stoyell
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Erin E Ross
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Lauren M Ostrowski
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Emily L Thorn
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Steven M Stufflebeam
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts.,Athinoula A. Martinos Center for Biomedical Imaging, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Amy K Morgan
- Psychological Assessment Center, Massachusetts General Hospital, Boston, Massachusetts
| | - Britt C Emerton
- Psychological Assessment Center, Massachusetts General Hospital, Boston, Massachusetts
| | - Mark A Kramer
- Department of Mathematics and Statistics, Boston University, Boston, Massachusetts
| | - Catherine J Chu
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
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Thomschewski A, Hincapié AS, Frauscher B. Localization of the Epileptogenic Zone Using High Frequency Oscillations. Front Neurol 2019; 10:94. [PMID: 30804887 PMCID: PMC6378911 DOI: 10.3389/fneur.2019.00094] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/23/2019] [Indexed: 01/22/2023] Open
Abstract
For patients with drug-resistant focal epilepsy, surgery is the therapy of choice in order to achieve seizure freedom. Epilepsy surgery foremost requires the identification of the epileptogenic zone (EZ), defined as the brain area indispensable for seizure generation. The current gold standard for identification of the EZ is the seizure-onset zone (SOZ). The fact, however that surgical outcomes are unfavorable in 40-50% of well-selected patients, suggests that the SOZ is a suboptimal biomarker of the EZ, and that new biomarkers resulting in better postsurgical outcomes are needed. Research of recent years suggested that high-frequency oscillations (HFOs) are a promising biomarker of the EZ, with a potential to improve surgical success in patients with drug-resistant epilepsy without the need to record seizures. Nonetheless, in order to establish HFOs as a clinical biomarker, the following issues need to be addressed. First, evidence on HFOs as a clinically relevant biomarker stems predominantly from retrospective assessments with visual marking, leading to problems of reproducibility and reliability. Prospective assessments of the use of HFOs for surgery planning using automatic detection of HFOs are needed in order to determine their clinical value. Second, disentangling physiologic from pathologic HFOs is still an unsolved issue. Considering the appearance and the topographic location of presumed physiologic HFOs could be immanent for the interpretation of HFO findings in a clinical context. Third, recording HFOs non-invasively via scalp electroencephalography (EEG) and magnetoencephalography (MEG) is highly desirable, as it would provide us with the possibility to translate the use of HFOs to the scalp in a large number of patients. This article reviews the literature regarding these three issues. The first part of the article focuses on the clinical value of invasively recorded HFOs in localizing the EZ, the detection of HFOs, as well as their separation from physiologic HFOs. The second part of the article focuses on the current state of the literature regarding non-invasively recorded HFOs with emphasis on findings and technical considerations regarding their localization.
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Affiliation(s)
- Aljoscha Thomschewski
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria,Department of Psychology, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Ana-Sofía Hincapié
- Montreal Neurological Institute and Hospital, McGill University, Montreal, QC, Canada
| | - Birgit Frauscher
- Montreal Neurological Institute and Hospital, McGill University, Montreal, QC, Canada,*Correspondence: Birgit Frauscher
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Halász P, Ujma PP, Fabó D, Bódizs R, Szűcs A. Epilepsy as a derailment of sleep plastic functions may cause chronic cognitive impairment - A theoretical review. Sleep Med Rev 2019; 45:31-41. [PMID: 30878843 DOI: 10.1016/j.smrv.2019.01.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Revised: 12/31/2018] [Accepted: 01/21/2019] [Indexed: 10/27/2022]
Abstract
We report on a peculiar way of chronic cognitive impairment associated with interictal epileptic activity during NREM sleep. We review three major groups of epilepsy: mesiotemporal epilepsy (MTLE) involving the epileptic derailment of the hippocampal declarative memory system; childhood developmental epileptic encephalopathies; and the spectrum disorders of the perisylvian communication network with the centrotemporal spike phenomenon, overarching child- and adulthood epilepsies, totaling up the majority of epilepsies in childhood. We outline high impact research-lines on the cognitive harm of epilepsy; causing specific or global cognitive decline through its interference with sleep plastic functions. We highlight the key role of interictal activity in the development of cognitive impairment and the fact that we are unarmed against this harm, antiepileptic pharmaco-therapy being ineffective against the interictal process marked by spikes and high frequency oscillations.
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Affiliation(s)
- Péter Halász
- National Institute of Clinical Neurosciences, Amerikai út 57, Budapest, H-1145, Hungary.
| | - Péter Przemyslaw Ujma
- Semmelweis University, Institute of Behavioral Sciences, Nagyvárad tér 4, Budapest, H-1089, Hungary
| | - Dániel Fabó
- National Institute of Clinical Neurosciences, Amerikai út 57, Budapest, H-1145, Hungary
| | - Róbert Bódizs
- National Institute of Clinical Neurosciences, Amerikai út 57, Budapest, H-1145, Hungary; Semmelweis University, Institute of Behavioral Sciences, Nagyvárad tér 4, Budapest, H-1089, Hungary
| | - Anna Szűcs
- National Institute of Clinical Neurosciences, Amerikai út 57, Budapest, H-1145, Hungary; Semmelweis University, Institute of Behavioral Sciences, Nagyvárad tér 4, Budapest, H-1089, Hungary
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Halász P, Kelemen A, Rosdy B, Rásonyi G, Clemens B, Szűcs A. Perisylvian epileptic network revisited. Seizure 2019; 65:31-41. [DOI: 10.1016/j.seizure.2018.12.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 12/04/2018] [Accepted: 12/06/2018] [Indexed: 11/27/2022] Open
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Simultaneously recorded intracranial and scalp high frequency oscillations help identify patients with poor postsurgical seizure outcome. Clin Neurophysiol 2018; 130:128-137. [PMID: 30529879 DOI: 10.1016/j.clinph.2018.10.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 09/20/2018] [Accepted: 10/15/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE High frequency oscillations (HFO) between 80-500 Hz are markers of epileptic areas in intracranial and maybe also scalp EEG. We investigate simultaneous recordings of scalp and intracranial EEG and hypothesize that scalp HFOs provide important additional clinical information in the presurgical setting. METHODS Spikes and HFOs were visually identified in all intracranial scalp EEG channels. Analysis of correlation of event location between intracranial and scalp EEG as well as relationship between events and the SOZ and zone of surgical removal was performed. RESULTS 24 patients could be included, 23 showed spikes and 19 HFOs on scalp recordings. In 15/19 patients highest scalp HFO rate was located over the implantation side, with 13 patients having the highest scalp and intracranial HFO rate over the same region. 17 patients underwent surgery, 7 became seizure free. Patients with poor post-operative outcome showed significantly more regions with HFO than those with seizure free outcome. CONCLUSIONS Scalp HFOs are mostly located over the SOZ. Widespread scalp HFOs are indicative of a larger epileptic network and associated with poor postsurgical outcome. SIGNIFICANCE Analysis of scalp HFO add clinically important information about the extent of epileptic areas during presurgical simultaneous scalp and intracranial EEG recordings.
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Jacobs J, Wu JY, Perucca P, Zelmann R, Mader M, Dubeau F, Mathern GW, Schulze-Bonhage A, Gotman J. Removing high-frequency oscillations: A prospective multicenter study on seizure outcome. Neurology 2018; 91:e1040-e1052. [PMID: 30120133 DOI: 10.1212/wnl.0000000000006158] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 06/12/2018] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To evaluate the use of interictal high-frequency oscillations (HFOs) in epilepsy surgery for prediction of postsurgical seizure outcome in a prospective multicenter trial. METHODS We hypothesized that a seizure-free outcome could be expected in patients in whom the surgical planning included the majority of HFO-generating brain tissue while a poor seizure outcome could be expected in patients in whom only a few such areas were planned to be resected. Fifty-two patients were included from 3 tertiary epilepsy centers during a 1-year period. Ripples (80-250 Hz) and fast ripples (250-500 Hz) were automatically detected during slow-wave sleep with chronic intracranial EEG in 2 centers and acute intraoperative electrocorticography in 1 patient. RESULTS There was a correlation between the removal of HFO-generating regions and seizure-free outcome at the group level for all patients. No correlation was found, however, for the center-specific analysis, and an individual prognostication of seizure outcome was true in only 36 patients (67%). Moreover, some patients became seizure-free without removal of the majority of HFO-generating tissue. The investigation of influencing factors, including comparisons of visual and automatic analysis, using a threshold analysis for areas with high HFO activity, and excluding contacts bordering the resection, did not result in improved prognostication. CONCLUSIONS On an individual patient level, a prediction of outcome was not possible in all patients. This may be due to the analysis techniques used. Alternatively, HFOs may be less specific for epileptic tissue than earlier studies have indicated.
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Affiliation(s)
- Julia Jacobs
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada.
| | - Joyce Y Wu
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Piero Perucca
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Rina Zelmann
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Malenka Mader
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Francois Dubeau
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Gary W Mathern
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Andreas Schulze-Bonhage
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
| | - Jean Gotman
- From the Department of Neuropediatrics and Muscular Diseases (J.J., M.M.) and Epilepsy Center (J.J., A.S.-B.), Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Germany; Division of Pediatric Neurology (J.Y.W., G.W.M.), David Geffen School of Medicine and Mattel Children's Hospital UCLA, Los Angeles, CA; and Montreal Neurological Institute (P.P., R.Z., F.D., J.G.), McGill University, Quebec, Canada
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Höller P, Trinka E, Höller Y. High-Frequency Oscillations in the Scalp Electroencephalogram: Mission Impossible without Computational Intelligence. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2018; 2018:1638097. [PMID: 30158959 PMCID: PMC6109569 DOI: 10.1155/2018/1638097] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 06/20/2018] [Accepted: 07/12/2018] [Indexed: 01/22/2023]
Abstract
High-frequency oscillations (HFOs) in the electroencephalogram (EEG) are thought to be a promising marker for epileptogenicity. A number of automated detection algorithms have been developed for reliable analysis of invasively recorded HFOs. However, invasive recordings are not widely applicable since they bear risks and costs, and the harm of the surgical intervention of implantation needs to be weighted against the informational benefits of the invasive examination. In contrast, scalp EEG is widely available at low costs and does not bear any risks. However, the detection of HFOs on the scalp represents a challenge that was taken on so far mostly via visual detection. Visual detection of HFOs is, in turn, highly time-consuming and subjective. In this review, we discuss that automated detection algorithms for detection of HFOs on the scalp are highly warranted because the available algorithms were all developed for invasively recorded EEG and do not perform satisfactorily in scalp EEG because of the low signal-to-noise ratio and numerous artefacts as well as physiological activity that obscures the tiny phenomena in the high-frequency range.
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Affiliation(s)
- Peter Höller
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
| | - Eugen Trinka
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
| | - Yvonne Höller
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
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Xie W, Ross EE, Kramer MA, Eden UT, Chu CJ. Timing matters: Impact of anticonvulsant drug treatment and spikes on seizure risk in benign epilepsy with centrotemporal spikes. Epilepsia Open 2018; 3:409-417. [PMID: 30187012 PMCID: PMC6119752 DOI: 10.1002/epi4.12248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2018] [Indexed: 11/22/2022] Open
Abstract
Objective Benign epilepsy with centrotemporal spikes (BECTS) is a common, self‐limited epilepsy syndrome affecting school‐age children. Classic interictal epileptiform discharges (IEDs) confirm diagnosis, and BECTS is presumed to be pharmacoresponsive. As seizure risk decreases in time with this disease, we hypothesize that the impact of IEDs and anticonvulsive drug (ACD) treatment on the risk of subsequent seizure will differ based on disease duration. Methods We calculate subsequent seizure risk following diagnosis in a large retrospective cohort of children with BECTS (n = 130), evaluating the impact of IEDs and ACD treatment in the first, second, third, and fourth years of disease. We use a Kaplan–Meier survival analysis and logistic regression models. Patients were censored if they were lost to follow‐up or if they changed group status. Results Two‐thirds of children had a subsequent seizure within 2 years of diagnosis. The majority of children had a subsequent seizure within 3 years despite treatment. The presence of IEDs on electroencephalography (EEG) did not impact subsequent seizure risk early in the disease. By the fourth year of disease, all children without IEDs remained seizure free, whereas one‐third of children with IEDs at this stage had a subsequent seizure. Conversely, ACD treatment corresponded with lower risk of seizure early in the disease but did not impact seizure risk in later years. Significance In this cohort, the majority of children with BECTS had a subsequent seizure despite treatment. In addition, ACD treatment and IEDs predicted seizure risk at specific points of disease duration. Future prospective studies are needed to validate these exploratory findings.
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Affiliation(s)
- Wenting Xie
- Department of Neurology Massachusetts General Hospital Boston Massachusetts U.S.A
| | - Erin E Ross
- Department of Neurology Massachusetts General Hospital Boston Massachusetts U.S.A
| | - Mark A Kramer
- Department of Mathematics and Statistics Boston University Boston Massachusetts U.S.A
| | - Uri T Eden
- Department of Mathematics and Statistics Boston University Boston Massachusetts U.S.A
| | - Catherine J Chu
- Department of Neurology Massachusetts General Hospital Boston Massachusetts U.S.A.,Harvard Medical School Boston Massachusetts U.S.A
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Detection of fast (40-150 Hz) oscillations from the ictal scalp EEG data of myoclonic seizures in pediatric patients. Brain Dev 2018; 40:397-405. [PMID: 29395662 DOI: 10.1016/j.braindev.2018.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 12/31/2017] [Accepted: 01/15/2018] [Indexed: 11/24/2022]
Abstract
OBJECTIVE We explored fast (40-150 Hz) oscillations (FOs) from the ictal scalp electroencephalogram (EEG) data of myoclonic seizures in pediatric patients to obtain insight into the pathophysiological mechanisms involved in the generation of myoclonic seizures. SUBJECTS AND METHODS The participants were 21 children (11 boys, 10 girls; age ranging from 5 months to 17 years 2 months) with myoclonic seizures associated with generalized (poly)spike-wave bursts in the ictal EEG data. The patients had heterogeneous etiologies and epilepsy diagnoses. In the ictal data, we detected FOs that clearly showed oscillatory morphology in filtered EEG traces and an outstanding spectral blob in time-frequency analysis. RESULTS We identified FOs in 61 (88.4%) of all 69 myoclonic seizures. Every patient had at least one myoclonic seizure-associated FO. The observed FOs were embedded in the spike component of (poly)spike-wave discharges, and they had a focal distribution with frontal predominance. They ranged in frequency from 41.0 to 123.0 Hz and involved both the gamma and ripple bands, and their spectral peak frequencies were higher in the group of patients with a genetic background free of apparent fundamental brain pathology than in the group of other patients (p = 0.019). CONCLUSION FOs were found to represent at least part of the cortical pathophysiological process in the generation of myoclonic seizures that should involve the thalamocortical network system.
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Gong P, Xue J, Qian P, Yang H, Liu X, Cai L, Bian K, Yang Z. Scalp-recorded high-frequency oscillations in childhood epileptic encephalopathy with continuous spike-and-wave during sleep with different etiologies. Brain Dev 2018; 40:299-310. [PMID: 29307466 DOI: 10.1016/j.braindev.2017.12.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 12/19/2017] [Accepted: 12/19/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To investigate high-frequency oscillations (HFOs) in epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) with different etiologies. METHODS Twenty-one CSWS patients treated with methylprednisolone were divided into structural group and genetic/unknown group. Comparisons were made between the two etiological groups: selected clinical variables including gender, age parameters, seizure frequencies and antiepileptic drugs; distribution of HFOs in pre-methylprednisolone electroencephalography (EEG) and percentage changes of HFOs and spikes after methylprednisolone treatment. RESULTS There were 7 patients (33%) in structural group and 14 patients (68%) in genetic/unknown group. No significant difference was found between the two groups regarding selected clinical variables. HFOs were found in 12 patients in pre-methylprednisolone EEG. The distribution of HFOs was focal and accordant with lesions in 5 of structural group, and it was also focal but in different brain regions in 7 of genetic/unknown group. The percentage reduction of total HFOs and spikes was 81% (158/195) and 19% (1956/10,037) in structural group, while 98% (315/323) and 55% (6658/12,258) in genetic/unknown group after methylprednisolone treatment. CONCLUSION The etiologies had no distinct correlation with some clinical characteristics in CSWS. HFOs recorded on scalp EEG might not only be used as makers of seizure-onset zone (SOZ), but also have association with functional disruption of brain networks. Both HFOs and spikes reduced more in genetic/unknown patients than that in structural patients after methylprednisolone treatment and HFOs were more sensitive to treatment than spikes.
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Affiliation(s)
- Pan Gong
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Jiao Xue
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Ping Qian
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Haipo Yang
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Xiaoyan Liu
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Lixin Cai
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China
| | - Kaigui Bian
- Institude of Network Computing and Information Systems, Peking University, No.5, Yiheyuan Street, Haidian District, Beijing 100871, China
| | - Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, No.1, Xi'anmen Street, Xicheng District, Beijing 100034, China.
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van Klink N, Mol A, Ferrier C, Hillebrand A, Huiskamp G, Zijlmans M. Beamforming applied to surface EEG improves ripple visibility. Clin Neurophysiol 2018; 129:101-111. [DOI: 10.1016/j.clinph.2017.10.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 09/20/2017] [Accepted: 10/05/2017] [Indexed: 01/17/2023]
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Abstract
BACKGROUND Epilepsy is a serious brain disorder characterized by recurrent unprovoked seizures. Approximately two-thirds of seizures can be controlled with antiepileptic medications (Kwan 2000). For some of the others, surgery can completely eliminate or significantly reduce the occurrence of disabling seizures. Localization of epileptogenic areas for resective surgery is far from perfect, and new tools are being investigated to more accurately localize the epileptogenic zone (the zone of the brain where the seizures begin) and improve the likelihood of freedom from postsurgical seizures. Recordings of pathological high-frequency oscillations (HFOs) may be one such tool. OBJECTIVES To assess the ability of HFOs to improve the outcomes of epilepsy surgery by helping to identify more accurately the epileptogenic areas of the brain. SEARCH METHODS For the latest update, we searched the Cochrane Epilepsy Group Specialized Register (25 July 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO, 25 July 2016), MEDLINE (Ovid, 1946 to 25 July 2016), CINAHL Plus (EBSCOhost, 25 July 2016), Web of Science (Thomson Reuters, 25 July 2016), ClinicalTrials.gov (25 July 2016), and the World Health Organization International Clinical Trials Registry Platform ICTRP (25 July 2016). SELECTION CRITERIA We included studies that provided information on the outcomes of epilepsy surgery for at least six months and which used high-frequency oscillations in making decisions about epilepsy surgery. DATA COLLECTION AND ANALYSIS The primary outcome of the review was the Engel Class Outcome System (class I = no disabling seizures, II = rare disabling seizures, III = worthwhile improvement, IV = no worthwhile improvement). Secondary outcomes were responder rate, International League Against Epilepsy (ILAE) epilepsy surgery outcome, frequency of adverse events from any source and quality of life outcomes. We intended to analyse outcomes via an aggregated data fixed-effect model meta-analysis. MAIN RESULTS Two studies representing 11 participants met the inclusion criteria. Both studies were small non-randomised trials, with no control group and no blinding. The quality of evidence for all outcomes was very low. The combination of these two studies resulted in 11 participants who prospectively used ictal HFOs for epilepsy surgery decision making. Results of the postsurgical seizure freedom Engel class I to IV outcome were determined over a period of 12 to 38 months (average 23.4 months) and indicated that six participants had an Engel class I outcome (seizure freedom), two had class II (rare disabling seizures), three had class III (worthwhile improvement). No adverse effects were reported. Neither study compared surgical results guided by HFOs versus surgical results guided without HFOs. AUTHORS' CONCLUSIONS No reliable conclusions can be drawn regarding the efficacy of using HFOs in epilepsy surgery decision making at present.
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Affiliation(s)
- David Gloss
- Charleston Area Medical CenterCAMC Neurology415 Morris StSuite 300CharlestonUSAWV 25301
| | - Sarah J Nevitt
- University of LiverpoolDepartment of BiostatisticsBlock F, Waterhouse Building1‐5 Brownlow HillLiverpoolUKL69 3GL
| | - Richard Staba
- University of CaliforniaDepartment of NeurologyReed Neurologic Research Center710 Westwood Plaza, Suite 1‐250Los AngelesCaliforniaUSA90095
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46
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Frauscher B, Bartolomei F, Kobayashi K, Cimbalnik J, van 't Klooster MA, Rampp S, Otsubo H, Höller Y, Wu JY, Asano E, Engel J, Kahane P, Jacobs J, Gotman J. High-frequency oscillations: The state of clinical research. Epilepsia 2017; 58:1316-1329. [PMID: 28666056 DOI: 10.1111/epi.13829] [Citation(s) in RCA: 209] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2017] [Indexed: 01/03/2023]
Abstract
Modern electroencephalographic (EEG) technology contributed to the appreciation that the EEG signal outside the classical Berger frequency band contains important information. In epilepsy, research of the past decade focused particularly on interictal high-frequency oscillations (HFOs) > 80 Hz. The first large application of HFOs was in the context of epilepsy surgery. This is now followed by other applications such as assessment of epilepsy severity and monitoring of antiepileptic therapy. This article reviews the evidence on the clinical use of HFOs in epilepsy with an emphasis on the latest developments. It highlights the growing literature on the association between HFOs and postsurgical seizure outcome. A recent meta-analysis confirmed a higher resection ratio for HFOs in seizure-free versus non-seizure-free patients. Residual HFOs in the postoperative electrocorticogram were shown to predict epilepsy surgery outcome better than preoperative HFO rates. The review further discusses the different attempts to separate physiological from epileptic HFOs, as this might increase the specificity of HFOs. As an example, analysis of sleep microstructure demonstrated a different coupling between HFOs inside and outside the epileptogenic zone. Moreover, there is increasing evidence that HFOs are useful to measure disease activity and assess treatment response using noninvasive EEG and magnetoencephalography. This approach is particularly promising in children, because they show high scalp HFO rates. HFO rates in West syndrome decrease after adrenocorticotropic hormone treatment. Presence of HFOs at the time of rolandic spikes correlates with seizure frequency. The time-consuming visual assessment of HFOs, which prevented their clinical application in the past, is now overcome by validated computer-assisted algorithms. HFO research has considerably advanced over the past decade, and use of noninvasive methods will make HFOs accessible to large numbers of patients. Prospective multicenter trials are awaited to gather information over long recording periods in large patient samples.
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Affiliation(s)
- Birgit Frauscher
- Department of Medicine and Center for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
| | - Fabrice Bartolomei
- National Institute of Health and Medical Research, Institute of Neurosciences of Systems, Aix Marseille University, Marseille, France
| | - Katsuhiro Kobayashi
- Department of Child Neurology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hospital, Kita-ku, Okayama, Japan
| | - Jan Cimbalnik
- International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic
| | - Maryse A van 't Klooster
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Stefan Rampp
- Department of Neurosurgery, University Hospital Erlangen, Erlangen, Germany
| | - Hiroshi Otsubo
- Division of Neurology, Department of Pediatrics, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yvonne Höller
- Department of Neurology, Christian Doppler Medical Center and Center for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Joyce Y Wu
- Division of Pediatric Neurology, Mattel Children's Hospital at UCLA, Los Angeles, California, U.S.A
| | - Eishi Asano
- Departments of Pediatrics and Neurology, Detroit Medical Center, Children's Hospital of Michigan, Wayne State University, Detroit, Michigan, U.S.A
| | - Jerome Engel
- Departments of Neurology, Neurobiology, and Psychiatry, Brain Research Institute, University of California, Los Angeles, Los Angeles, California, U.S.A
| | - Philippe Kahane
- Department of Neurology, Grenoble-Alpes University Hospital and Grenoble-Alpes University, Grenoble, France
| | - Julia Jacobs
- Department of Neuropediatrics and Muscular Diseases, University Medical Center Freiburg, Freiburg, Germany
| | - Jean Gotman
- Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
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47
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Nariai H, Beal J, Galanopoulou AS, Mowrey WB, Bickel S, Sogawa Y, Jehle R, Shinnar S, Moshé SL. Scalp EEG Ictal gamma and beta activity during infantile spasms: Evidence of focality. Epilepsia 2017; 58:882-892. [PMID: 28397999 DOI: 10.1111/epi.13735] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE We investigated temporal and spatial characteristics of ictal gamma and beta activity on scalp EEG during spasms in patients with West syndrome (WS) to evaluate potential focal cortical onset. METHODS A total of 1,033 spasms from 34 patients with WS of various etiologies were analyzed on video-electroencephalography (EEG) using time-frequency analysis. Ictal gamma (35-90 Hz) and beta (15-30 Hz) activities were correlated with visual symmetry of spasms, objective EMG (electromyography) analysis, and etiology of WS. RESULTS Prior to the ictal motor manifestation, focal ictal gamma activity emerged from one hemisphere (71%, 24/34) or from midline (26%, 9/34), and was rarely simultaneously bilateral (3%, 1/34). Focal ictal beta activity emerged from either one hemisphere (68%, 23/34) or from midline (32%, 11/34). Onsets of focal ictal gamma and beta activity were most commonly observed around the parietal areas. Focal ictal gamma activity propagated faster than ictal beta activity to adjacent electrodes (median: 65 vs. 170 msec, p < 0.01), and to contralateral hemisphere (median: 100 vs. 170 msec, p = 0.01). Asymmetric peak amplitude of ictal gamma activity in the centroparietal areas (C3-P3 vs. C4-P4) correlated with asymmetric semiology. On the other hand, most of the visually symmetric spasms showed asymmetry in peak amplitude and interhemispheric onset latency difference in both ictal gamma and beta activity. SIGNIFICANCE Spasms may be a seizure with focal electrographic onset regardless of visual symmetry. Asymmetric involvement of ictal gamma activity to the centroparietal areas may determine the motor manifestations in WS. Scalp EEG ictal gamma and beta activity may be useful to demonstrate localized seizure onset in infants with WS.
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Affiliation(s)
- Hiroki Nariai
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Jules Beal
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Aristea S Galanopoulou
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Dominick P. Purpura Department Neuroscience, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Wenzhu B Mowrey
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Stephan Bickel
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Yoshimi Sogawa
- Department of Pediatrics and Neurology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A
| | - Rana Jehle
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Shlomo Shinnar
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, U.S.A
| | - Solomon L Moshé
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Department of Pediatrics, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, New York, U.S.A.,Dominick P. Purpura Department Neuroscience, Albert Einstein College of Medicine, Bronx, New York, U.S.A
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Kobayashi K, Endoh F, Agari T, Akiyama T, Akiyama M, Hayashi Y, Shibata T, Hanaoka Y, Oka M, Yoshinaga H, Date I. Complex observation of scalp fast (40-150 Hz) oscillations in West syndrome and related disorders with structural brain pathology. Epilepsia Open 2017; 2:260-266. [PMID: 29588955 PMCID: PMC5719855 DOI: 10.1002/epi4.12043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2017] [Indexed: 11/08/2022] Open
Abstract
We investigated the relationship between the scalp distribution of fast (40-150 Hz) oscillations (FOs) and epileptogenic lesions in West syndrome (WS) and related disorders. Subjects were 9 pediatric patients with surgically confirmed structural epileptogenic pathology (age at initial electroencephalogram [EEG] recording: mean 7.1 months, range 1-22 months). The diagnosis was WS in 7 patients, Ohtahara syndrome in 1, and a transitional state from Ohtahara syndrome to WS in the other. In the scalp EEG data of these patients, we conservatively detected FOs, and then examined the distribution of FOs. In five patients, the scalp distribution of FOs was consistent and concordant with the lateralization of cerebral pathology. In another patient, FOs were consistently dominant over the healthy cerebral hemisphere, and the EEG was relatively low in amplitude over the pathological atrophic hemisphere. In the remaining 3 patients, the dominance of FOs was inconsistent and, in 2 of these patients, the epileptogenic hemisphere was reduced in volume, which may result from atrophy or hypoplasia. The correspondence between the scalp distribution of FOs and the epileptogenic lesion should be studied, taking the type of lesion into account. The factors affecting scalp FOs remain to be elucidated.
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Affiliation(s)
- Katsuhiro Kobayashi
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Fumika Endoh
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Takashi Agari
- Epilepsy Center Okayama University Hospital Okayama Japan.,Department of Neurological Surgery Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan
| | - Tomoyuki Akiyama
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Mari Akiyama
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Yumiko Hayashi
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Takashi Shibata
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Yoshiyuki Hanaoka
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Makio Oka
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Harumi Yoshinaga
- Department of Child Neurology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan.,Epilepsy Center Okayama University Hospital Okayama Japan
| | - Isao Date
- Epilepsy Center Okayama University Hospital Okayama Japan.,Department of Neurological Surgery Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences and Okayama University Hospital Okayama Japan
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Bourel-Ponchel E, Mahmoudzadeh M, Berquin P, Wallois F. Local and Distant Dysregulation of Synchronization Around Interictal Spikes in BECTS. Front Neurosci 2017; 11:59. [PMID: 28239337 PMCID: PMC5301021 DOI: 10.3389/fnins.2017.00059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 01/26/2017] [Indexed: 11/21/2022] Open
Abstract
Objective: High Density electroencephalography (HD EEG) is the reference non-invasive technique to investigate the dynamics of neuronal networks in Benign Epilepsy with Centro-Temporal Spikes (BECTS). Analysis of local dynamic changes surrounding Interictal Epileptic Spikes (IES) might improve our knowledge of the mechanisms that propel neurons to the hypersynchronization of IES in BECTS. Transient distant changes in the dynamics of neurons populations may also interact with neuronal networks involved in various functions that are impaired in BECTS patients. Methods: HD EEG (64 electrodes) of eight well-characterized BECTS patients (8 males; mean age: 7.2 years, range: 5–9 years) were analyzed. Unilateral IES were selected in 6 patients. They were bilateral and independent in 2 other patients. This resulted in a total of 10 groups of IES. Time-frequency analysis was performed on HD EEG epochs around the peak of the IES (±1000 ms), including phase-locked and non-phase-locked activities to the IES. The time frequency analyses were calculated for the frequencies between 4 and 200 Hz. Results: Time-frequency analysis revealed two patterns of dysregulation of the synchronization between neuronal networks preceding and following hypersynchronization of interictal spikes (±400 ms) in the epileptogenic zone. Dysregulation consists of either desynchronization (n = 6) or oscillating synchronization (n = 4) (4–50 Hz) surrounding the IES. The 2 patients with bilateral IES exhibited only local desynchronization whatever the IES considered. Distant desynchronization in low frequencies within the same window occurs simultaneously in bilateral frontal, temporal and occipital areas (n = 7). Significance: Using time-frequency analysis of HD EEG data in a well-defined population of BECTS, we demonstrated repeated complex changes in the dynamics of neuronal networks not only during, but also, before and after the IES. In the epileptogenic zone, our results found more complex reorganization of the local network than initially thought. In line with previous results obtained at a microscopic or macroscopic level, these changes suggested the variability strategies of neuronal assemblies to raise IES. Distant changes from the epileptogenic zone in desynchronization observed in the same time window suggested interactions between larger embedded networks and opened new avenues about their possible role in the underlying mechanism leading to cognitive deficits.
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Affiliation(s)
- Emilie Bourel-Ponchel
- Institut National de la Santé et de la Recherche Médicale U 1105, GRAMFC, CURS, CHU Amiens Picardie - Site SudSalouël, Amiens, France; Fonctional Exploration of the Pediatric Nervous System, CHU Amiens Picardie - Site SudSalouël, Amiens, France
| | - Mahdi Mahmoudzadeh
- Institut National de la Santé et de la Recherche Médicale U 1105, GRAMFC, CURS, CHU Amiens Picardie - Site SudSalouël, Amiens, France; Fonctional Exploration of the Pediatric Nervous System, CHU Amiens Picardie - Site SudSalouël, Amiens, France
| | - Patrick Berquin
- Institut National de la Santé et de la Recherche Médicale U 1105, GRAMFC, CURS, CHU Amiens Picardie - Site SudSalouël, Amiens, France; Neuropediatry Unit, CHU Amiens Picardie - Site SudSalouël, Amiens, France
| | - Fabrice Wallois
- Institut National de la Santé et de la Recherche Médicale U 1105, GRAMFC, CURS, CHU Amiens Picardie - Site SudSalouël, Amiens, France; Fonctional Exploration of the Pediatric Nervous System, CHU Amiens Picardie - Site SudSalouël, Amiens, France
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50
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Scalp-recorded high-frequency oscillations in atypical benign partial epilepsy. Clin Neurophysiol 2016; 127:3306-13. [DOI: 10.1016/j.clinph.2016.07.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 06/09/2016] [Accepted: 07/06/2016] [Indexed: 02/04/2023]
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