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Campora N, Princich JP, Nasimbera A, Cordisco S, Villanueva M, Oddo S, Giagante B, Kochen S. Stereo-EEG features of temporal and frontal lobe seizures with loss of consciousness. Neurosci Conscious 2024; 2024:niae003. [PMID: 38618487 PMCID: PMC11015893 DOI: 10.1093/nc/niae003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 12/11/2023] [Accepted: 04/03/2024] [Indexed: 04/16/2024] Open
Abstract
The loss of consciousness (LOC) during seizures is one of the most striking features that significantly impact the quality of life, even though the neuronal network involved is not fully comprehended. We analyzed the intracerebral patterns in patients with focal drug-resistant epilepsy, both with and without LOC. We assessed the localization, lateralization, stereo electroencephalography (SEEG) patterns, seizure duration, and the quantification of contacts exhibiting electrical discharge. The degree of LOC was quantified using the Consciousness Seizure Scale. Thirteen patients (40 seizures) with focal drug-resistant epilepsy underwent SEEG. In cases of temporal lobe epilepsy (TLE, 6 patients and 15 seizures), LOC occurred more frequently in seizures with mesial rather than lateral temporal lobe onset. On the other hand, in cases of frontal lobe epilepsy (7 patients; 25 seizures), LOC was associated with pre-frontal onset, a higher number of contacts with epileptic discharge compared to the onset count and longer seizure durations. Our study revealed distinct characteristics during LOC depending on the epileptogenic zone. For temporal lobe seizures, LOC was associated with mesial seizure onset, whereas in frontal lobe epilepsy, seizure with LOC has a significant increase in contact showing epileptiform discharge and a pre-frontal onset. This phenomenon may be correlated with the broad neural network required to maintain consciousness, which can be affected in different ways, resulting in LOC.
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Affiliation(s)
- Nuria Campora
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Juan Pablo Princich
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Alejandro Nasimbera
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Santiago Cordisco
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Manuela Villanueva
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Silvia Oddo
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
| | - Brenda Giagante
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
| | - Silvia Kochen
- Neuroscience Department, El Cruce Hospital, Florencio Varela, Argentina
- Studies in Neuroscience and Complex Systems (ENyS), CONICET, Florencio Varela, Buenos Aires 1888, Argentina
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Tyulmenkova A, Zwick A, Dillon T, Isgor C. Progressive generalized tonic-clonic seizures in a transgenic mouse model of adult-onset epilepsy: Implications for morphological changes in cortico-limbic and brainstem structures. Epilepsy Res 2023; 194:107178. [PMID: 37295319 PMCID: PMC10527249 DOI: 10.1016/j.eplepsyres.2023.107178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/21/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023]
Abstract
Video/cortical electroencephalography (EEG) is monitored to assess progressive severity of generalized tonic clonic seizures (GTCSs) in a transgenic mouse model of adult-onset epilepsy with increased death risk. The mice overexpress the brain derived neurotrophic factor (BDNF) in the forebrain under the calcium/calmodulin dependent protein kinase 2a (termed TgBDNF) and develop GTCSs in response to tail suspension/cage agitation stimulation at 3-4 months of age. With successive GTCSs (a total of 16 across 10 weeks of assessment), seizures became more severe as evidenced by increased duration of postictal generalized EEG suppression (PGES) associated with loss of posture/consciousness. Mice also developed spike wave discharges with behavioral arrest during the seizure recovery that increased in duration as a function of number of GTCSs. Overall seizure duration (from preictal spike to offset of PGES) and ictal spectral power (full spectra) were also increased. Half of the TgBDNF mice expired following a long period of PGES at the last recorded GTCS. Seizure-evoked general arousal impairment was associated with a striking decrease in total number of gigantocellular neurons of the brainstem nucleus pontis oralis along with increase in volumes of the anterior cingulate cortex and dorsal dentate gyrus in severely convulsive TgBDNF mice compared to litter-matched WT controls and non-convulsive TgBDNF mice. The latter effect was accompanied with an increase in total number of hippocampal granule neurons. These results provide structure-function associations in an animal model of adult-onset GTCSs that progressively increase in severity with clinical relevance for sudden unexpected death following generalized seizures.
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Affiliation(s)
- Anastasia Tyulmenkova
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Amanda Zwick
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Tashi Dillon
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Ceylan Isgor
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
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3
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Qin Y, Tong X, Li W, Zhang L, Zhang Y, Li X, Yang J, Qin K, Lei D, Gong Q, Zhou D, An D. Divergent Anatomical Correlates and Functional Network Connectivity Patterns in Temporal Lobe Epilepsy with and Without Depression. Brain Topogr 2021; 34:525-536. [PMID: 33973138 DOI: 10.1007/s10548-021-00848-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 05/05/2021] [Indexed: 02/05/2023]
Abstract
Epilepsy and depression were proposed to facilitate each other reciprocally through common neurobiological anomalies, especially the prefrontal-limbic-subcortical abnormalities. Yet neuroimaging patterns of higher-order cognitive networks and neuroanatomical correlates were rarely compared in temporal lobe epilepsy patients with (TLE-D) and without depression (TLE-N). We collected T1-weighted structural and resting-state functional MRI data from 20 TLE-D, 31 TLE-N and 20 healthy controls (HCs) and performed analyses including hippocampal volume (HCV), cortical thickness, gray matter volume (GMV) and whole-brain functional network connectivity (FNC) across three groups. Imaging differences were related to clinical and psychological measurements. TLE-D demonstrated disrupted functional role of subcortical (SUB) and higher-order cognitive networks compared to TLE-N and HCs. In TLE-D, GMV in the right supplementary motor area (SMA) and FNC between the dorsal attention (DAN) and SUB were attenuated compared to TLE-N and HCs, FNC between SUB and the visual network (VIS) decreased compared to HCs. GMV in the right SMA was negatively correlated with depression severity and some symptoms. Combined, explicit emotion regulation may be impaired in TLE-D. Meanwhile, compared to HCs, TLE-N showed smaller HCVs, TLE-D and TLE-N showed smaller GMV in the medial orbital frontal gyrus and right hippocampus and hippocampal gyrus, possibly implying predisposition of epileptic activities to co-morbid depression. Our findings suggest distinct anatomical and FNC patterns in TLE-D and TLE-N. More than prefrontal-limbic-subcortical anomalies, disrupted higher-order cognitive network may contribute to depression in TLE, providing new potential treatment targets for depression and calling attention to relation between cognitive dysfunction and co-morbid depression.
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Affiliation(s)
- Yingjie Qin
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xin Tong
- Department of Neurology, West China Second Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Wei Li
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Le Zhang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yingying Zhang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xiuli Li
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jing Yang
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Kun Qin
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Du Lei
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Qiyong Gong
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
| | - Dongmei An
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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Sattin D, Magnani FG, Bartesaghi L, Caputo M, Fittipaldo AV, Cacciatore M, Picozzi M, Leonardi M. Theoretical Models of Consciousness: A Scoping Review. Brain Sci 2021; 11:535. [PMID: 33923218 PMCID: PMC8146510 DOI: 10.3390/brainsci11050535] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 11/17/2022] Open
Abstract
The amount of knowledge on human consciousness has created a multitude of viewpoints and it is difficult to compare and synthesize all the recent scientific perspectives. Indeed, there are many definitions of consciousness and multiple approaches to study the neural correlates of consciousness (NCC). Therefore, the main aim of this article is to collect data on the various theories of consciousness published between 2007-2017 and to synthesize them to provide a general overview of this topic. To describe each theory, we developed a thematic grid called the dimensional model, which qualitatively and quantitatively analyzes how each article, related to one specific theory, debates/analyzes a specific issue. Among the 1130 articles assessed, 85 full texts were included in the prefinal step. Finally, this scoping review analyzed 68 articles that described 29 theories of consciousness. We found heterogeneous perspectives in the theories analyzed. Those with the highest grade of variability are as follows: subjectivity, NCC, and the consciousness/cognitive function. Among sub-cortical structures, thalamus, basal ganglia, and the hippocampus were the most indicated, whereas the cingulate, prefrontal, and temporal areas were the most reported for cortical ones also including the thalamo-cortical system. Moreover, we found several definitions of consciousness and 21 new sub-classifications.
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Affiliation(s)
- Davide Sattin
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
- Experimental Medicine and Medical Humanities-PhD Program, Biotechnology and Life Sciences Department and Center for Clinical Ethics, Insubria University, 21100 Varese, Italy
| | - Francesca Giulia Magnani
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
| | - Laura Bartesaghi
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
| | - Milena Caputo
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
| | | | - Martina Cacciatore
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
| | - Mario Picozzi
- Center for Clinical Ethics, Biotechnology and Life Sciences Department, Insubria University, 21100 Varese, Italy;
| | - Matilde Leonardi
- Neurology, Public Health, Disability Unit—Scientific Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy; (F.G.M.); (L.B.); (M.C.); (M.C.); (M.L.)
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Sattin D, Duran D, Visintini S, Schiaffi E, Panzica F, Carozzi C, Rossi Sebastiano D, Visani E, Tobaldini E, Carandina A, Citterio V, Magnani FG, Cacciatore M, Orena E, Montano N, Caldiroli D, Franceschetti S, Picozzi M, Matilde L. Analyzing the Loss and the Recovery of Consciousness: Functional Connectivity Patterns and Changes in Heart Rate Variability During Propofol-Induced Anesthesia. Front Syst Neurosci 2021; 15:652080. [PMID: 33889078 PMCID: PMC8055941 DOI: 10.3389/fnsys.2021.652080] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
The analysis of the central and the autonomic nervous systems (CNS, ANS) activities during general anesthesia (GA) provides fundamental information for the study of neural processes that support alterations of the consciousness level. In the present pilot study, we analyzed EEG signals and the heart rate (HR) variability (HRV) in a sample of 11 patients undergoing spinal surgery to investigate their CNS and ANS activities during GA obtained with propofol administration. Data were analyzed during different stages of GA: baseline, the first period of anesthetic induction, the period before the loss of consciousness, the first period after propofol discontinuation, and the period before the recovery of consciousness (ROC). In EEG spectral analysis, we found a decrease in posterior alpha and beta power in all cortical areas observed, except the occipital ones, and an increase in delta power, mainly during the induction phase. In EEG connectivity analysis, we found a significant increase of local efficiency index in alpha and delta bands between baseline and loss of consciousness as well as between baseline and ROC in delta band only and a significant reduction of the characteristic path length in alpha band between the baseline and ROC. Moreover, connectivity results showed that in the alpha band there was mainly a progressive increase in the number and in the strength of incoming connections in the frontal region, while in the beta band the parietal region showed mainly a significant increase in the number and in the strength of outcoming connections values. The HRV analysis showed that the induction of anesthesia with propofol was associated with a progressive decrease in complexity and a consequent increase in the regularity indexes and that the anesthetic procedure determined bradycardia which was accompanied by an increase in cardiac sympathetic modulation and a decrease in cardiac parasympathetic modulation during the induction. Overall, the results of this pilot study showed as propofol-induced anesthesia caused modifications on EEG signal, leading to a "rebalance" between long and short-range cortical connections, and had a direct effect on the cardiac system. Our data suggest interesting perspectives for the interactions between the central and autonomic nervous systems for the modulation of the consciousness level.
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Affiliation(s)
- Davide Sattin
- Neurology, Public Health, Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
- Clinical and Experimental Medicine and Medical Humanities-PhD Program, Insubria University, Varese, Italy
| | - Dunja Duran
- Clinical and Experimental Epileptology Division, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Sergio Visintini
- Department of Neurosurgery, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Elena Schiaffi
- Neurophysiology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Ferruccio Panzica
- Clinical Engineering Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Carla Carozzi
- Department of Anaesthesia, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | | | - Elisa Visani
- Clinical and Experimental Epileptology Division, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Eleonora Tobaldini
- Department of Internal Medicine, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Angelica Carandina
- Department of Internal Medicine, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Valeria Citterio
- Department of Internal Medicine, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Francesca Giulia Magnani
- Neurology, Public Health, Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Martina Cacciatore
- Neurology, Public Health, Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Eleonora Orena
- Department of Anaesthesia, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Nicola Montano
- Department of Internal Medicine, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Dario Caldiroli
- Department of Anaesthesia, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Silvana Franceschetti
- Neurophysiology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Mario Picozzi
- Center for Clinical Ethics, Biotechnology and Life Sciences Department, Insubria University, Varese, Italy
| | - Leonardi Matilde
- Neurology, Public Health, Disability Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
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Dheer P, Pati S, Chowdhury KK, Majumdar KK. Enhanced gamma band mutual information is associated with impaired consciousness during temporal lobe seizures. Heliyon 2021; 6:e05769. [PMID: 33409386 PMCID: PMC7773881 DOI: 10.1016/j.heliyon.2020.e05769] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/24/2020] [Accepted: 12/14/2020] [Indexed: 11/24/2022] Open
Abstract
Background Epileptic seizures are characterized by aberrant synchronization. We hypothesized that higher synchronization across the seizure onset zone (SOZ) channels during a temporal lobe seizure contributes to impaired consciousness. New method All symmetric bivariate synchronization measures were extended to multivariate measure by a principal component analysis (PCA) based technique. A novel nonparametric method has been proposed to test the statistical significance between increased synchronization across the seizure onset zone (SOZ) channels and reduced consciousness. Results Increased synchronization in the gamma band towards seizure termination significantly contributes to impaired consciousness (p < 0.1). Synchronization reaches its peak in the extratemporal region (frontal lobe) ahead of the temporal region (p < 0.05). Synchronization is prominent in beta and gamma bands by most methods and it is more in the second half of seizure duration than in the first (p < 0.05). Conclusions Mutual information is the only synchronization measure out of the six that we studied, whose increase can be associated with the loss of consciousness in a statistically significant way.
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Affiliation(s)
- Puneet Dheer
- Systems Science and Informatics Unit, Indian Statistical Institute, 8th Mile, Mysore Road, Bangalore, India, 560059
| | - Sandipan Pati
- UAB Epilepsy Center, Department of Neurology, University of Alabama at Birmingham, CIRC 312, 1719 6th Avenue South, Birmingham, AL, 35294, USA
| | - Kalyan Kumar Chowdhury
- Statistical Quality Control Unit, Indian Statistical Institute, 8th Mile, Mysore Road, Bangalore, 560059, India
| | - Kaushik Kumar Majumdar
- Systems Science and Informatics Unit, Indian Statistical Institute, 8th Mile, Mysore Road, Bangalore, India, 560059
- Corresponding author.
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7
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Quantitative characteristics of spike-wave paroxysms in genetic generalized epilepsy. Clin Neurophysiol 2020; 131:1230-1240. [DOI: 10.1016/j.clinph.2020.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/17/2020] [Accepted: 03/12/2020] [Indexed: 11/20/2022]
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8
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Tan Z, Long X, Tian F, Huang L, Xie F, Li S. Alterations in Brain Metabolites in Patients with Epilepsy with Impaired Consciousness: A Case-Control Study of Interictal Multivoxel 1H-MRS Findings. AJNR Am J Neuroradiol 2019; 40:245-252. [PMID: 30679211 DOI: 10.3174/ajnr.a5944] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/01/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Previous studies have shown perfusion abnormalities in the thalamus and upper brain stem in patients with epilepsy with impaired consciousness. We hypothesized that these areas associated with consciousness will also show metabolic abnormalities. However, metabolic abnormalities in those areas correlated with consciousness has not been characterized with multiple-voxel 1H-MRS. In this study, we investigated the metabolic alterations in these brain regions and assessed the correlation between seizure features and metabolic alterations. MATERIALS AND METHODS Fifty-seven patients with epilepsy and 24 control subjects underwent routine MR imaging and 3D multiple-voxel 1H-MRS. Patients were divided into 3 subgroups: focal impaired awareness seizures (n = 18), primary generalized tonic-clonic seizures (n = 19), and secondary generalized tonic-clonic seizures (n = 20). The measured metabolite alterations in NAA/Cr, NAA/(Cr + Cho), and Cho/Cr ratios in brain regions associated with the consciousness network were compared between the patient and control groups. ROIs were placed in the bilateral inferior frontal gyrus, supramarginal gyrus, cingulate gyrus, precuneus, thalamus, and upper brain stem. Correlations between clinical parameters (epilepsy duration and seizure frequency) and metabolite alterations were analyzed. RESULTS Significantly lower NAA/Cr and NAA/(Cho + Cr) ratios (P < .05 and < .01, respectively) were observed in the bilateral thalamus and upper brain stem in all experimental groups, and significantly high Cho/Cr ratios (P < .05) were observed in the right thalamus in the focal impaired awareness seizures group. There were no significant differences in metabolite ratios among the 3 patient groups (P > .05). The secondary generalized tonic-clonic seizures group showed a negative correlation between the duration of epilepsy and the NAA/(Cr + Cho) ratio in the bilateral thalamus (P < .05). CONCLUSIONS Metabolic alterations were observed in the brain stem and thalamus in patients with epilepsy with impaired consciousness.
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Affiliation(s)
- Z Tan
- From the Departments of Neurology (Z.T., X.L., F.T., L.H., S.L.)
| | - X Long
- From the Departments of Neurology (Z.T., X.L., F.T., L.H., S.L.)
| | - F Tian
- From the Departments of Neurology (Z.T., X.L., F.T., L.H., S.L.)
| | - L Huang
- From the Departments of Neurology (Z.T., X.L., F.T., L.H., S.L.)
| | - F Xie
- Radiology (F.X.), Xiangya Hospital, Central South University, Changsha, China
| | - S Li
- From the Departments of Neurology (Z.T., X.L., F.T., L.H., S.L.)
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9
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Palanca BJA, Maybrier HR, Mickle AM, Farber NB, Hogan RE, Trammel ER, Spencer JW, Bohnenkamp DD, Wildes TS, Ching S, Lenze E, Basner M, Kelz MB, Avidan MS. Cognitive and Neurophysiological Recovery Following Electroconvulsive Therapy: A Study Protocol. Front Psychiatry 2018; 9:171. [PMID: 29867602 PMCID: PMC5960711 DOI: 10.3389/fpsyt.2018.00171] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 04/13/2018] [Indexed: 01/01/2023] Open
Abstract
Electroconvulsive therapy (ECT) employs the elective induction of generalizes seizures as a potent treatment for severe psychiatric illness. As such, ECT provides an opportunity to rigorously study the recovery of consciousness, reconstitution of cognition, and electroencephalographic (EEG) activity following seizures. Fifteen patients with major depressive disorder refractory to pharmacologic therapy will be enrolled (Clinicaltrials.gov, NCT02761330). Adequate seizure duration will be confirmed following right unilateral ECT under etomidate anesthesia. Patients will then undergo randomization for the order in which they will receive three sequential treatments: etomidate + ECT, ketamine + ECT, and ketamine + sham ECT. Sessions will be repeated in the same sequence for a total of six treatments. Before each session, sensorimotor speed, working memory, and executive function will be assessed through a standardized cognitive test battery. After each treatment, the return of purposeful responsiveness to verbal command will be determined. At this point, serial cognitive assessments will begin using the same standardized test battery. The presence of delirium and changes in depression severity will also be ascertained. Sixty-four channel EEG will be acquired throughout baseline, ictal, and postictal epochs. Mixed-effects models will correlate the trajectories of cognitive recovery, clinical outcomes, and EEG metrics over time. This innovative research design will answer whether: (1) time to return of responsiveness will be prolonged with ketamine + ECT compared with ketamine + sham ECT; (2) time of restoration to baseline function in each cognitive domain will take longer after ketamine + ECT than after ketamine + sham ECT; (3) postictal delirium is associated with delayed restoration of baseline function in all cognitive domains; and (4) the sequence of reconstitution of cognitive domains following the three treatments in this study is similar to that occurring after an isoflurane general anesthetic (NCT01911195). Sub-studies will assess the relationships of cognitive recovery to the EEG preceding, concurrent, and following individual ECT sessions. Overall, this study will lead the development of biomarkers for tailoring the cogno-affective recovery of patients undergoing ECT.
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Affiliation(s)
- Ben J A Palanca
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States.,Division of Biology and Biomedical Sciences, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Hannah R Maybrier
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Angela M Mickle
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Nuri B Farber
- Department of Psychiatry, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - R Edward Hogan
- Department of Neurology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Emma R Trammel
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - J Wylie Spencer
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Donald D Bohnenkamp
- Department of Psychiatry, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Troy S Wildes
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - ShiNung Ching
- Division of Biology and Biomedical Sciences, Washington University School of Medicine in St. Louis, St Louis, MO, United States.,Department of Electrical Systems and Engineering, Washington University, St Louis, MO, United States
| | - Eric Lenze
- Department of Psychiatry, Washington University School of Medicine in St. Louis, St Louis, MO, United States
| | - Mathias Basner
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
| | - Max B Kelz
- Department of Anesthesiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, United States
| | - Michael S Avidan
- Department of Anesthesiology, Washington University School of Medicine in St. Louis, St Louis, MO, United States.,Department of Surgery, Washington University School of Medicine in St. Louis, St Louis, MO, United States
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10
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Coleman DK, Long B, Koyfman A. Clinical Mimics: An Emergency Medicine-Focused Review of Syncope Mimics. J Emerg Med 2017; 54:81-89. [PMID: 29110977 DOI: 10.1016/j.jemermed.2017.09.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 09/14/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND Syncope is an event that causes a transient loss of consciousness (LOC) secondary to global cerebral hypoperfusion. The transient nature of the event can make diagnosis in the emergency department (ED) difficult, as symptoms have often resolved by time of initial presentation. The symptoms and presentation of syncope are similar to many other conditions, which can lead to difficulty in establishing a diagnosis in the ED. OBJECTIVE This review evaluates patients presenting with a history concerning for possible syncope, mimics of syncope, and approach to managing syncope mimics. DISCUSSION Syncope is caused by transient LOC secondary to global cerebral hypoperfusion. Many conditions can present similarly to syncope, making diagnosis in the ED difficult. Some of the most emergent conditions include seizures, stroke, metabolic disorders, and head trauma. Other nonemergent conditions include cataplexy, pseudosyncope, or deconditioning. Many laboratory studies and imaging can be nondiagnostic during ED evaluation. For patients presenting with apparent syncope, immediate treatment should focus on identifying and treating life-threatening conditions. History and physical examination can help guide further diagnostic evaluation and management. CONCLUSIONS Patients with apparent syncope should be evaluated for potential immediate life-threatening conditions. A thorough history and physical examination can aid in distinguishing syncope from common mimics and help identify and subsequently treat life-threatening conditions.
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Affiliation(s)
- Diana K Coleman
- Department of Emergency Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas
| | - Brit Long
- Department of Emergency Medicine, San Antonio Military Medical Center, Fort Sam Houston, Texas
| | - Alex Koyfman
- Department of Emergency Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas
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11
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Morgan VL, Englot DJ, Rogers BP, Landman BA, Cakir A, Abou-Khalil BW, Anderson AW. Magnetic resonance imaging connectivity for the prediction of seizure outcome in temporal lobe epilepsy. Epilepsia 2017; 58:1251-1260. [PMID: 28448683 DOI: 10.1111/epi.13762] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2017] [Indexed: 01/21/2023]
Abstract
OBJECTIVE Currently, approximately 60-70% of patients with unilateral temporal lobe epilepsy (TLE) remain seizure-free 3 years after surgery. The goal of this work was to develop a presurgical connectivity-based biomarker to identify those patients who will have an unfavorable seizure outcome 1-year postsurgery. METHODS Resting-state functional and diffusion-weighted 3T magnetic resonance imaging (MRI) was acquired from 22 unilateral (15 right, 7 left) patients with TLE and 35 healthy controls. A seizure propagation network was identified including ipsilateral (to seizure focus) and contralateral hippocampus, thalamus, and insula, with bilateral midcingulate and precuneus. Between each pair of regions, functional connectivity based on correlations of low frequency functional MRI signals, and structural connectivity based on streamline density of diffusion MRI data were computed and transformed to metrics related to healthy controls of the same age. RESULTS A consistent connectivity pattern representing the network expected in patients with seizure-free outcome was identified using eight patients who were seizure-free at 1-year postsurgery. The hypothesis that increased similarity to the model would be associated with better seizure outcome was tested in 14 other patients (Engel class IA, seizure-free: n = 5; Engel class IB-II, favorable: n = 4; Engel class III-IV, unfavorable: n = 5) using two similarity metrics: Pearson correlation and Euclidean distance. The seizure-free connectivity model successfully separated all the patients with unfavorable outcome from the seizure-free and favorable outcome patients (p = 0.0005, two-tailed Fisher's exact test) through the combination of the two similarity metrics with 100% accuracy. No other clinical and demographic predictors were successful in this regard. SIGNIFICANCE This work introduces a methodologic framework to assess individual patients, and demonstrates the ability to use network connectivity as a potential clinical tool for epilepsy surgery outcome prediction after more comprehensive validation.
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Affiliation(s)
- Victoria L Morgan
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A.,Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Dario J Englot
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A.,Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A
| | - Baxter P Rogers
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A
| | - Bennett A Landman
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A.,Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Ahmet Cakir
- Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Bassel W Abou-Khalil
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A
| | - Adam W Anderson
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, U.S.A.,Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, U.S.A
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Xie F, Xing W, Wang X, Liao W, Shi W. Altered states of consciousness in epilepsy: a DTI study of the brain. Int J Neurosci 2016; 127:667-672. [PMID: 27575403 DOI: 10.1080/00207454.2016.1229668] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Fangfang Xie
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Wu Xing
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Xiaoyi Wang
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Weihua Liao
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
| | - Wei Shi
- Department of Radiology, Xiangya Hospital Central South University, Changsha, China
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13
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Magne Bjølseth T, Engedal K, Šaltytė Benth J, Bergsholm P, Strømnes Dybedal G, Lødøen Gaarden T, Tanum L. Speed of recovery from disorientation may predict the treatment outcome of electroconvulsive therapy (ECT) in elderly patients with major depression. J Affect Disord 2016; 190:178-186. [PMID: 26519638 DOI: 10.1016/j.jad.2015.10.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/17/2015] [Accepted: 10/10/2015] [Indexed: 11/29/2022]
Abstract
BACKGROUND No study has previously investigated whether the speed of recovery from disorientation in the post-ictal period may predict the short-term treatment outcome of electroconvulsive therapy (ECT). METHODS This longitudinal cohort study included 57 elderly patients with unipolar or bipolar major depression, aged 60-85 years, treated with formula-based ECT. Treatment outcome was assessed weekly during the ECT course using the 17-item Hamilton Rating Scale for Depression (HRSD17). The post-ictal reorientation time (PRT) was assessed at the first and third treatments. RESULTS Longer PRTs at the first and third treatments predicted a more rapid decline and a lower end-point in continuous HRSD17 scores (p=0.002 and 0.019, respectively). None of the patients who recovered from disorientation in less than 5 min met the remission criterion, defined as an HRSD17 score of 7 or less. A greater increment in stimulus dosage from the first to the third ECT session rendered a smaller relative decline in PRT (p<0.001). LIMITATIONS The limited number of subjects may reduce the generalizability of the findings. CONCLUSIONS The speed of recovery from disorientation at the first and third sessions seems to be a predictor of the treatment outcome of formula-based ECT, at least in elderly patients with major depression. It remains to be clarified how the PRT may be utilized to guide stimulus dosing.
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Affiliation(s)
- Tor Magne Bjølseth
- Department of Geriatric Psychiatry, Diakonhjemmet Hospital, Oslo, Norway.
| | - Knut Engedal
- Norwegian Centre for Aging and Health, Vestfold Health Trust, Tønsberg, Norway
| | - Jūratė Šaltytė Benth
- Institute of Clinical Medicine, Campus Ahus, University of Oslo, Norway; HØKH, Research Centre, Akershus University Hospital, Norway
| | - Per Bergsholm
- Department of Emergency Mental Health Services, Oslo University Hospital, Ullevål, Norway
| | | | | | - Lars Tanum
- Department of Research and Development in Mental Health, Akershus University Hospital, Norway
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Hu Y, Mi X, Xu X, Fang W, Zeng K, Yang M, Li C, Wang S, Li M, Wang X. The Brain Activity in Brodmann Area 17: A Potential Bio-Marker to Predict Patient Responses to Antiepileptic Drugs. PLoS One 2015; 10:e0139819. [PMID: 26439500 PMCID: PMC4595505 DOI: 10.1371/journal.pone.0139819] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 07/28/2015] [Indexed: 12/29/2022] Open
Abstract
In this study, we aimed to predict newly diagnosed patient responses to antiepileptic drugs (AEDs) using resting-state functional magnetic resonance imaging tools to explore changes in spontaneous brain activity. We recruited 21 newly diagnosed epileptic patients, 8 drug-resistant (DR) patients, 11 well-healed (WH) patients, and 13 healthy controls. After a 12-month follow-up, 11 newly diagnosed epileptic patients who showed a poor response to AEDs were placed into the seizures uncontrolled (SUC) group, while 10 patients were enrolled in the seizure-controlled (SC) group. By calculating the amplitude of fractional low-frequency fluctuations (fALFF) of blood oxygen level-dependent signals to measure brain activity during rest, we found that the SUC patients showed increased activity in the bilateral occipital lobe, particularly in the cuneus and lingual gyrus compared with the SC group and healthy controls. Interestingly, DR patients also showed increased activity in the identical cuneus and lingual gyrus regions, which comprise Brodmann's area 17 (BA17), compared with the SUC patients; however, these abnormalities were not observed in SC and WH patients. The receiver operating characteristic (ROC) curves indicated that the fALFF value of BA17 could differentiate SUC patients from SC patients and healthy controls with sufficient sensitivity and specificity prior to the administration of medication. Functional connectivity analysis was subsequently performed to evaluate the difference in connectivity between BA17 and other brain regions in the SUC, SC and control groups. Regions nearby the cuneus and lingual gyrus were found positive connectivity increased changes or positive connectivity changes with BA17 in the SUC patients, while remarkably negative connectivity increased changes or positive connectivity decreased changes were found in the SC patients. Additionally, default mode network (DMN) regions showed negative connectivity increased changes or negative changes with BA17 in the SUC patients. The abnormal increased in BA17 activity may be a key point that plays a substantial role in facilitating seizure onset.
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Affiliation(s)
- Yida Hu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Xiujuan Mi
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Xin Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Weidong Fang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Kebin Zeng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Mingming Yang
- Department of Pediatrics, Chongqing City Hospital of Traditional Chinese Medicine, Chongqing, People’s Republic of China
| | - Chenyu Li
- Department of Neurology, Chongqing City Hospital of Traditional Chinese Medicine, Chongqing, People’s Republic of China
| | - Shasha Wang
- The Nursing Department, Chongqing Three Gorges Central Hospital, Chongqing, People’s Republic of China
| | - Minghui Li
- The Nursing Department, First Hospital of Shanxi Medical University, Taiyuan, People’s Republic of China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
- * E-mail:
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15
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Morgan VL, Rogers BP, Abou-Khalil B. Segmentation of the thalamus based on BOLD frequencies affected in temporal lobe epilepsy. Epilepsia 2015; 56:1819-27. [PMID: 26360535 DOI: 10.1111/epi.13186] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2015] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Temporal lobe epilepsy is associated with functional changes throughout the brain, particularly including a putative seizure propagation network involving the hippocampus, insula, and thalamus. We identified a specified frequency range where functional connectivity in this network was related to duration of disease. Then, to identify specific thalamic nuclei involved in seizure propagation, we determined the subregions of the thalamus that have increased resting functional oscillations in this frequency range. METHODS Resting-state functional magnetic resonance imaging (fMRI) was acquired from 20 patients with unilateral temporal lobe epilepsy (TLE; 14 right and 6 left) and 20 healthy controls who were each age and gender matched to a specific patient. Wavelet-based fMRI connectivity mapping across the network was computed at each frequency to determine those frequencies where connectivity significantly decreases with duration of disease consistent with impairment due to repeated seizures. The voxel-wise power of the spontaneous blood oxygenation fluctuations of this frequency band was computed in the thalamus of each subject. RESULTS Functional connectivity was impaired in the proposed seizure propagation network over a specific range (0.0067-0.013 Hz and 0.024-0.032 Hz) of blood oxygenation oscillations. Increased power in this frequency band (<0.032 Hz) was detected bilaterally in the pulvinar and anterior nucleus of the thalamus of healthy controls, and was increased over the ipsilateral thalamus compared to the contralateral thalamus in TLE. SIGNIFICANCE This study identified frequencies of impaired connectivity in a TLE seizure propagation network and used them to localize the anterior nucleus and pulvinar of the thalamus as subregions most susceptible to TLE seizures. Further examinations of these frequencies in healthy and TLE subjects may provide unique information relating to the mechanism of seizure propagation and potential treatment using electrical stimulation.
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Affiliation(s)
- Victoria L Morgan
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Baxter P Rogers
- Department of Radiology and Radiological Sciences, Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee, U.S.A
| | - Bassel Abou-Khalil
- Department of Neurology, Vanderbilt University, Nashville, Tennessee, U.S.A
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16
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Morgan VL, Conrad BN, Abou-Khalil B, Rogers BP, Kang H. Increasing structural atrophy and functional isolation of the temporal lobe with duration of disease in temporal lobe epilepsy. Epilepsy Res 2014; 110:171-8. [PMID: 25616470 DOI: 10.1016/j.eplepsyres.2014.12.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 11/21/2014] [Accepted: 12/04/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Due to pharmacoresistant seizures and the underutilization of surgical treatments, a large number of temporal lobe epilepsy (TLE) patients experience seizures for years or decades. The goal of this study was to generate a predictive model of duration of disease with the least number of parameters possible in order to identify and quantify the significant volumetric and functional indicators of TLE progression. METHODS Two cohorts of subjects including 12 left TLE, 21 right TLE and 20 healthy controls (duration = 0) were imaged on a 3T MRI scanner using high resolution T1-weighted structural MRI and 20 min of resting functional MRI scanning. Multivariate linear regression methods were used to compute a predictive model of duration of disease using 49 predictors including functional connectivity and gray matter volumes computed from these images. RESULTS No model developed from the full set of data accurately predicted the duration of disease across the entire range from 3 to 50 years. We then performed the regression on 35 subjects with durations of disease in the range 10 to 35 years. The resulting predictive model showed that longer durations were associated with reductions in functional connectivity from the ipsilateral temporal lobe to the contralateral temporal lobe, precuneus and mid cingulate, and with decreases in volume of the ipsilateral hippocampus and pallidum. CONCLUSIONS Functional and volumetric parameters accurately predicted duration of disease in TLE. The findings suggest that TLE is associated with a gradual functional isolation and significant progressive structural atrophy of the ipsilateral temporal lobe over years of duration in the range of 10-35 years. Furthermore, these changes can also be detected in the contralateral hemisphere in these patients, but to a lesser degree.
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Affiliation(s)
- Victoria L Morgan
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA.
| | - Benjamin N Conrad
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
| | | | - Baxter P Rogers
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Hakmook Kang
- Department of Biostatistics, Vanderbilt University, Nashville, TN, USA
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17
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Morgan VL, Abou-Khalil B, Rogers BP. Evolution of functional connectivity of brain networks and their dynamic interaction in temporal lobe epilepsy. Brain Connect 2014; 5:35-44. [PMID: 24901036 DOI: 10.1089/brain.2014.0251] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study presents a cross-sectional investigation of functional networks in temporal lobe epilepsy (TLE) as they evolve over years of disease. Networks of interest were identified based on a priori hypotheses: the network of seizure propagation ipsilateral to the seizure focus, the same regions contralateral to seizure focus, the cross hemisphere network of the same regions, and a cingulate midline network. Resting functional magnetic resonance imaging data were acquired for 20 min in 12 unilateral TLE patients, and 12 age- and gender-matched healthy controls. Functional changes within and between the four networks as they evolve over years of disease were quantified by standard measures of static functional connectivity and novel measures of dynamic functional connectivity. The results suggest an initial disruption of cross-hemispheric networks and an increase in static functional connectivity in the ipsilateral temporal network accompanying the onset of TLE seizures. As seizures progress over years, the static functional connectivity across the ipsilateral network diminishes, while dynamic functional connectivity measures show the functional independence of this ipsilateral network from the network of midline regions of the cingulate declines. This implies a gradual breakdown of the seizure onset and early propagation network involving the ipsilateral hippocampus and temporal lobe as it becomes more synchronous with the network of regions responsible for secondary generalization of the seizures, a process that may facilitate the spread of seizures across the brain. Ultimately, the significance of this evolution may be realized in relating it to symptoms and treatment outcomes of TLE.
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Affiliation(s)
- Victoria L Morgan
- 1 Department of Radiology, Vanderbilt University , Nashville, Tennessee
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18
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Pollak L, Gandelman-Marton R, Margolin N, Boxer M, Blatt I. Clinical and electroencephalographic findings in acutely ill adults with non-convulsive vs convulsive status epilepticus. Acta Neurol Scand 2014; 129:405-11. [PMID: 24571568 DOI: 10.1111/ane.12200] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/08/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Non-convulsive status epilepticus (NCSE) indicates a change in the mental state with no motor manifestations, being a clinical expression of prolonged epileptiform activity. In contrast to convulsive status epilepticus (CSE), no unified treatment recommendations have been proposed so far. We were interested to review the clinical and encephalographic characteristics in hospitalized patients with NCSE and CSE and compare their treatment and outcome. PATIENTS AND METHODS The electroencephalographic recording records of adult patients with electrographic status epilepticus were retrieved. Patients' clinical records were then analyzed. RESULTS Fifty-three patients with CSE and 25 patients with NCSE were identified. Background diseases, neuroimaging findings and complications were similar in CSE and NCSE. Anoxia was a more frequent etiological factor only for myoclonic SE. Patients with CSE presented more often with coma. The number of drugs used for treatment was similar, but anesthetics drugs were administered more frequently in patients with CSE. The 30-day mortality rate was higher in myoclonic SE and generalized tonic-clonic SE, but the outcome on discharge in terms of survival and recovery was comparable between CSE and NCSE. CONCLUSIONS The results of the present study show that the clinical parameters of NCSE in acutely ill patients do not substantially differ from those of patients with CSE. Moreover, despite more severe mental changes and the need for more anesthetic drugs for treatment of CSE, the final outcome did not differ between both groups. This might indicate that NCSE in acutely ill patients should be regarded as seriously as CSE.
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Affiliation(s)
- L. Pollak
- Department of Neurology; The Assaf Harofeh Medical Center; Zerifin Israel
- The Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - R. Gandelman-Marton
- Department of Neurology; The Assaf Harofeh Medical Center; Zerifin Israel
- The Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - N. Margolin
- Department of Neurology; The Sheba Medical Center; Ramat-Gan Israel
- The Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - M. Boxer
- Department of Neurology; The Sheba Medical Center; Ramat-Gan Israel
- The Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - I. Blatt
- Department of Neurology; The Sheba Medical Center; Ramat-Gan Israel
- The Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
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Tang V, Michaelis R, Kwan P. Psychobehavioral therapy for epilepsy. Epilepsy Behav 2014; 32:147-55. [PMID: 24418662 DOI: 10.1016/j.yebeh.2013.12.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 12/16/2022]
Abstract
Growing evidence suggests a bidirectional interaction between epileptic seizures and psychological states, fuelling the interest in the development and application of psychobehavioral therapy for people with epilepsy (PWE). The objective of this article is to review the various psychobehavioral therapies in regard to their application, hypothesized mechanisms, and effectiveness. Most psychobehavioral therapy aims at improving psychological well-being and seizure control. Behavioral approaches, cognitive-behavioral therapy (CBT), and mind-body interventions are the most widely applied approaches for PWE. Cognitive-behavioral therapy, mind-body approaches, and multimodel educative interventions have consistently demonstrated positive effects on enhancing well-being. Nevertheless, the effects on seizure control remain inconsistent, partly attributable to small clinical trials and inadequate control groups. Assessor-blinded randomized controlled trials with sufficient power and carefully defined therapeutic components corresponding with objective and subjective outcome measures are recommended for future trial designs.
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Affiliation(s)
- Venus Tang
- Department of Clinical Psychology, Prince of Wales Hospital, Hospital Authority, Hong Kong; Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong.
| | - Rosa Michaelis
- Gemeinschaftskrankenhaus Herdecke, Department of Neurology, Gerhard-Kienle-Weg 4, 58313 Herdecke, Germany; Faculty of Health, Department of Medicine, Chair for Theory of Medicine, Integrative and Anthroposophic Medicine, Integrated Curriculum for Anthroposophic Medicine, University of Witten/Herdecke, Alfred-Herrhausen-Straße 50, 58448 Witten, Germany; Andrews/Reiter Epilepsy Research Program, 19265 Deer Hill Rd., Hidden Valley Lake, CA 95467, USA
| | - Patrick Kwan
- Departments of Medicine and Neurology, The University of Melbourne, Royal Melbourne Hospital, Melbourne, Australia; Division of Neurology, Department of Medicine and Therapeutics, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong
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Detyniecki K, Blumenfeld H. Consciousness of seizures and consciousness during seizures: are they related? Epilepsy Behav 2014; 30:6-9. [PMID: 24126026 PMCID: PMC6287500 DOI: 10.1016/j.yebeh.2013.09.018] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 09/13/2013] [Indexed: 10/26/2022]
Abstract
Recent advances have been made in the network mechanisms underlying impairment of consciousness during seizures. However, less is known about patient awareness of their own seizures. Studying patient reports or documentation of their seizures is currently the most commonly utilized mechanism to scientifically measure patient awareness of seizures. The purpose of this review is to summarize the available evidence regarding the accuracy of patient seizure counts and identify the variables that may influence unreliable seizure reporting. Several groups looking at patient documentation of seizures during continuous EEG monitoring show that patients do not report as many as 50% of their seizures. These studies also suggest that seizures accompanied by loss of consciousness, arising from the left hemisphere or the temporal lobe, or occurring during sleep are associated with significantly reduced reporting. Baseline memory performance does not appear to have a major influence on the accuracy of seizure report. Further prospective studies using validated ictal behavioral testing as well as using correlation with newer electrophysiological and neuroimaging techniques for seizure localization are needed to more fully understand the mechanisms of underreporting of seizures. Better methods to alert caregivers about unrecognized seizures and to improve seizure documentation are under investigation.
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Affiliation(s)
- Kamil Detyniecki
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
| | - Hal Blumenfeld
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA,Department of Neurobiology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA,Department of Neurosurgery, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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21
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Holmes MJ, Yang X, Landman BA, Ding Z, Kang H, Abou-Khalil B, Sonmezturk HH, Gore JC, Morgan VL. Functional networks in temporal-lobe epilepsy: a voxel-wise study of resting-state functional connectivity and gray-matter concentration. Brain Connect 2013; 3:22-30. [PMID: 23150897 DOI: 10.1089/brain.2012.0103] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Temporal-lobe epilepsy (TLE) involves seizures that typically originate in the hippocampus. There is evidence that seizures involve anatomically and functionally connected brain networks within and beyond the temporal lobe. Many studies have explored the effect of TLE on gray matter and resting-state functional connectivity in the brain. However, the relationship between structural and functional changes has not been fully explored. The goal of this study was to investigate the relationship between gray matter concentration (GMC) and functional connectivity in TLE at the voxel level. A voxel-wise linear regression analysis was performed between GMC maps and whole-brain resting-state functional connectivity maps to both the left thalamus (Lthal) and the left hippocampus (LH) in a group of 15 patients with left TLE. Twenty regions were found that exhibited GMC decreases linearly correlated with resting-state functional connectivity to either the LH or the Lthal in the patient group only. A subset of these regions had significantly reduced GMC, and one of these regions also had reduced functional connectivity to the LH in TLE compared to the controls. These results suggest a network of impairment in left TLE where more severe reductions in GMC accompany decreases (LH, Lthal, right midcingulate gyrus, left precuneus, and left postcentral gyrus) or increases (LH to right thalamus) in resting functional connectivity. However, direct relationships between these imaging parameters and disease characteristics in these regions have yet to be established.
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Affiliation(s)
- Martha J Holmes
- Institute of Imaging Science, Vanderbilt University, Nashville, Tennessee 37232-2310, USA
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22
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Prognostic value of early epileptic seizures on mortality and functional disability in acute stroke: the Dijon Stroke Registry (1985-2010). J Neurol 2012. [PMID: 23180187 DOI: 10.1007/s00415-012-6756-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We aimed to evaluate the prognostic value of early epileptic seizures after stroke. All consecutive patients with a first-ever stroke were prospectively identified within the population of Dijon, France, thanks to a population-based registry, from 1985 to 2010. Early epileptic seizures were defined as seizures occurring within 14 days after stroke onset. Outcomes were 1-month and 1-year mortality, and severe functional handicap at discharge. Of the 4,411 stroke patients included, data about seizures were available in 4,358 (98.8, 53.5 % women, mean age, 74.1 ± 14.8 years). Among these patients, 134 (3.1 %) had early seizures. Stroke patients with early seizures differed from those without seizures, as there was a higher proportion of hemorrhagic stroke, higher blood glucose level at admission, smoking status, and more frequent impaired. Higher risks of 1-month and 1-year mortality in patients with early seizures (unadjusted HR 1.45, 95 % CI 1.00-2.10; HR = 1.59, 95 % CI 1.21-2.09, respectively) disappeared (HR 0.71, 95 % CI 0.49-1.08 and HR 0.85, 95 % CI 0.64-1.17) after adjustment for stroke severity and other confounding factors. Early seizures were associated with severe handicap in unadjusted analyses (OR 2.07, 95 % CI 1.46-2.95) but the association was no longer significant after multivariable adjustment (OR 1.12, 95 % CI 0.69-1.83). Early epileptic seizures were not associated with higher risks of mortality at 1 month and 1 year or with unfavorable functional outcome after acute stroke. The adverse effects of epileptic seizures may not be distinguishable from stroke severity, which is strongly related to epileptic seizures.
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Abstract
Consciousness is essential to normal human life. In epileptic seizures consciousness is often transiently lost, which makes it impossible for the individual to experience or respond. These effects have huge consequences for safety, productivity, emotional health, and quality of life. To prevent impaired consciousness in epilepsy, it is necessary to understand the mechanisms that lead to brain dysfunction during seizures. Normally the consciousness system-a specialised set of cortical-subcortical structures-maintains alertness, attention, and awareness. Advances in neuroimaging, electrophysiology, and prospective behavioural testing have shed light on how epileptic seizures disrupt the consciousness system. Diverse seizure types, including absence, generalised tonic-clonic, and complex partial seizures, converge on the same set of anatomical structures through different mechanisms to disrupt consciousness. Understanding of these mechanisms could lead to improved treatment strategies to prevent impairment of consciousness and improve the quality of life of people with epilepsy.
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Affiliation(s)
- Hal Blumenfeld
- Departments of Neurology, Neurobiology, and Neurosurgery, Yale University School of Medicine, New Haven, CT 06520, USA.
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Morgan VL, Sonmezturk HH, Gore JC, Abou-Khalil B. Lateralization of temporal lobe epilepsy using resting functional magnetic resonance imaging connectivity of hippocampal networks. Epilepsia 2012; 53:1628-35. [PMID: 22779926 DOI: 10.1111/j.1528-1167.2012.03590.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE Early surgical intervention can be advantageous in the treatment of refractory temporal lobe epilepsy (TLE). The success of TLE surgery relies on accurate lateralization of the seizure onset. The purpose of this study was to determine whether resting functional MRI (fMRI) connectivity mapping of the hippocampus has the potential to complement conventional presurgical evaluations in distinguishing left from right TLE. In addition, we sought to determine whether this same network might separate patients with favorable from unfavorable postoperative outcomes. METHODS Resting fMRI acquisitions were performed on 21 patients with TLE and 15 healthy controls. The patients included seven patients with left TLE and seven patients with right TLE with seizure-free postoperative outcome, and five patients with left TLE and two patients with right TLE with recurring seizures after surgery. Functional connectivity maps to each hippocampus were determined for each subject and were compared between the controls and the seizure-free patients with left TLE and with right TLE. The one network identified was then quantified in the patients with TLE and recurring seizures. KEY FINDINGS The resting functional connectivity between the right hippocampus and the ventral lateral nucleus of the right thalamus was the most statistically significant network to distinguish between seizure-free patients with left TLE and with right TLE with high sensitivity and specificity. This connectivity was also significantly greater in the seizure-free patients with left TLE than the healthy controls. Finally, six of the seven patients in whom seizures recurred after surgery had connectivity values in this network unlike those who were seizure-free. SIGNIFICANCE This study identified a region in the ventral lateral nucleus of the right thalamus whose connectivity to the hippocampi separates left from right TLE subjects. This suggests that the quantification of resting-state functional magnetic resonance imaging (MRI) connectivity across this network may be a potential indicator of lateralization of TLE that may be added to other presurgical MRI assessments. Further validation in a larger, independent cohort is required.
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Affiliation(s)
- Victoria L Morgan
- Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee, USA.
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Yang L, Shklyar I, Lee HW, Ezeani CC, Anaya J, Balakirsky S, Han X, Enamandram S, Men C, Cheng JY, Nunn A, Mayer T, Francois C, Albrecht M, Hutchison AL, Yap EL, Ing K, Didebulidze G, Xiao B, Hamid H, Farooque P, Detyniecki K, Giacino JT, Blumenfeld H. Impaired consciousness in epilepsy investigated by a prospective responsiveness in epilepsy scale (RES). Epilepsia 2011; 53:437-47. [PMID: 22150524 DOI: 10.1111/j.1528-1167.2011.03341.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Impaired consciousness in epileptic seizures has a major negative impact on patient quality of life. Prior work on epileptic unconsciousness has mainly used retrospective and nonstandardized methods. Our goal was to validate and to obtain initial data using a standardized prospective testing battery. METHODS The responsiveness in epilepsy scale (RES) was used on 52 patients during continuous video-electroencephalography (EEG) monitoring. RES begins with higher-level questions and commands, and switches adaptively to more basic sensorimotor responses depending on patient performance. RES continues after seizures and includes postictal memory testing. Scoring was conducted based on video review. KEY FINDINGS Testing on standardized seizure simulations yielded good intrarater and interrater reliability. We captured 59 seizures from 18 patients (35% of participants) during 1,420 h of RES monitoring. RES impairment was greatest during and after tonic-clonic seizures, less in partial seizures, and minimal in auras and subclinical seizures. In partial seizures, ictal RES impairment was significantly greater if EEG changes were present. Maximum RES impairment (lowest ictal score) was also significantly correlated with long postictal recovery time, and poor postictal memory. SIGNIFICANCE We found that prospective testing of responsiveness during seizures is feasible and reliable. RES impairment was related to EEG changes during seizures, as well as to postictal memory deficits and recovery time. With a larger patient sample it is hoped that this approach can identify brain networks underlying specific components of impaired consciousness in seizures. This may allow the development of improved treatments targeted at preventing dysfunction in these networks.
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Affiliation(s)
- Li Yang
- Department of Neurology, Yale University School of Medicine, New Haven, CT 06520-8018, USA
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27
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Abstract
Recent advances have shown much in common between epilepsy and other disorders of consciousness. Behavior in epileptic seizures often resembles a transient vegetative or minimally conscious state. These disorders all converge on the "consciousness system" -the bilateral medial and lateral fronto-parietal association cortex and subcortical arousal systems. Epileptic unconsciousness has enormous clinical significance leading to accidental injuries, decreased work and school productivity, and social stigmatization. Ongoing research to better understand the mechanisms of impaired consciousness in epilepsy, including neuroimaging studies and fundamental animal models, will hopefully soon enable treatment trails to reduce epileptic unconsciousness and improve patient quality of life.
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Affiliation(s)
- Hal Blumenfeld
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
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Danielson NB, Guo JN, Blumenfeld H. The default mode network and altered consciousness in epilepsy. Behav Neurol 2011; 24:55-65. [PMID: 21447899 PMCID: PMC3150226 DOI: 10.3233/ben-2011-0310] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The default mode network has been hypothesized based on the observation that specific regions of the brain are consistently activated during the resting state and deactivated during engagement with task. The primary nodes of this network, which typically include the precuneus/posterior cingulate, the medial frontal and lateral parietal cortices, are thought to be involved in introspective and social cognitive functions. Interestingly, this same network has been shown to be selectively impaired during epileptic seizures associated with loss of consciousness. Using a wide range of neuroimaging and electrophysiological modalities, decreased activity in the default mode network has been confirmed during complex partial, generalized tonic-clonic, and absence seizures. In this review we will discuss these three seizure types and will focus on possible mechanisms by which decreased default mode network activity occurs. Although the specific mechanisms of onset and propagation differ considerably across these seizure types, we propose that the resulting loss of consciousness in all three types of seizures is due to active inhibition of subcortical arousal systems that normally maintain default mode network activity in the awake state. Further, we suggest that these findings support a general “network inhibition hypothesis”, by which active inhibition of arousal systems by seizures in certain cortical regions leads to cortical deactivation in other cortical areas. This may represent a push-pull mechanism similar to that seen operating between cortical networks under normal conditions.
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Affiliation(s)
- Nathan B Danielson
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8018, USA
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29
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Abstract
Monaco F, Mula M, Cavanna AE. The neurophilosophy of epileptic experiences.Background:Specific alterations of consciousness have a central role in the phenomenological description of epileptic seizures and in the patient's subjective reports.Methods:This article discusses the use of philosophical methodology within a neurological framework to understand consciousness.Results:How the alterations in consciousness are experienced by patients with epilepsy depends largely on the localization of the underlying neurophysiological dysfuntion.Discussion:Rigorous conceptual analysis of ictal experience reports can help to illuminate the study of consciousness.
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Affiliation(s)
- Francesco Monaco
- Department of Neurology, Amedeo Avogadro University, Novara, Italy
| | - Marco Mula
- Department of Neurology, Amedeo Avogadro University, Novara, Italy
| | - Andrea E Cavanna
- Department of Neuropsychiatry, Birmingham and Solihull Mental Health NHS Foundation Trust, University of Birmingham, Birmingham, UK
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Luo C, Li Q, Lai Y, Xia Y, Qin Y, Liao W, Li S, Zhou D, Yao D, Gong Q. Altered functional connectivity in default mode network in absence epilepsy: a resting-state fMRI study. Hum Brain Mapp 2011; 32:438-49. [PMID: 21319269 DOI: 10.1002/hbm.21034] [Citation(s) in RCA: 197] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Dysfunctional default mode network (DMN) has been observed in various mental disorders, including epilepsy (see review Broyd et al. [2009]: Neurosci Biobehav Rev 33:279–296). Because interictal epileptic discharges may affect DMN, resting-state fMRI was used in this study to determine DMN functional connectivity in 14 healthy controls and 12 absence epilepsy patients. To avoid interictal epileptic discharge effects, testing was performed within interictal durations when there were no interictal epileptic discharges. Cross-correlation functional connectivity analysis with seed at posterior cingulate cortex, as well as region-wise calculation in DMN, revealed decreased integration within DMN in the absence epilepsy patients. Region-wise functional connectivity among the frontal, parietal, and temporal lobe was significantly decreased in the patient group. Moreover, functional connectivity between the frontal and parietal lobe revealed a significant negative correlation with epilepsy duration. These findings indicated DMN abnormalities in patients with absence epilepsy, even during resting interictal durations without interictal epileptic discharges. Abnormal functional connectivity in absence epilepsy may reflect abnormal anatomo-functional architectural integration in DMN, as a result of cognitive mental impairment and unconsciousness during absence seizure.
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Affiliation(s)
- Cheng Luo
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
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Yang L, Morland TB, Schmits K, Rawson E, Narasimhan P, Motelow JE, Purcaro MJ, Peng K, Raouf S, DeSalvo MN, Oh T, Wilkerson J, Bod J, Srinivasan A, Kurashvili P, Anaya J, Manza P, Danielson N, Ransom CB, Huh L, Elrich S, Padin-Rosado J, Naidu Y, Detyniecki K, Hamid H, Fattahi P, Astur R, Xiao B, Duckrow RB, Blumenfeld H. A prospective study of loss of consciousness in epilepsy using virtual reality driving simulation and other video games. Epilepsy Behav 2010; 18:238-46. [PMID: 20537593 PMCID: PMC2914099 DOI: 10.1016/j.yebeh.2010.04.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 04/07/2010] [Accepted: 04/12/2010] [Indexed: 10/19/2022]
Abstract
Patients with epilepsy are at risk of traffic accidents when they have seizures while driving. However, driving is an essential part of normal daily life in many communities, and depriving patients of driving privileges can have profound consequences for their economic and social well-being. In the current study, we collected ictal performance data from a driving simulator and two other video games in patients undergoing continuous video/EEG monitoring. We captured 22 seizures in 13 patients and found that driving impairment during seizures differed in terms of both magnitude and character, depending on the seizure type. Our study documents the feasibility of a prospective study of driving and other behaviors during seizures through the use of computer-based tasks. This methodology may be applied to further describe differential driving impairment in specific types of seizures and to gain data on anatomical networks disrupted in seizures that impair consciousness and driving safety.
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Affiliation(s)
- Li Yang
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiang Ya Road, Changsha, Hunan, 410008, China
| | - Thomas B. Morland
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Kristen Schmits
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Elizabeth Rawson
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Poojitha Narasimhan
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Joshua E. Motelow
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Michael J. Purcaro
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Kathy Peng
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Saned Raouf
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Matthew N. DeSalvo
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Taemin Oh
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Jerome Wilkerson
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Jessica Bod
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Aditya Srinivasan
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Pimen Kurashvili
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Joseph Anaya
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Peter Manza
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Nathan Danielson
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Christopher B. Ransom
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Linda Huh
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Susan Elrich
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Jose Padin-Rosado
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Yamini Naidu
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Kamil Detyniecki
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Hamada Hamid
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Pooia Fattahi
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Robert Astur
- Department of Psychiatry, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
- Olin Neuropsychiatry Research Center, Institute of Living, 200 Retreat Avenue, Whitehall Building, Hartford, CT 06106
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, 87 Xiang Ya Road, Changsha, Hunan, 410008, China
| | - Robert B. Duckrow
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
| | - Hal Blumenfeld
- Department of Neurology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
- Department of Neurobiology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
- Department of Neurosurgery, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA
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Long JJ, Shen B, Luo T, Stewart L, McMurran TJ, Leung LS. Pilocarpine model of temporal lobe epilepsy shows enhanced response to general anesthetics. Exp Neurol 2009; 219:308-18. [DOI: 10.1016/j.expneurol.2009.05.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 05/23/2009] [Accepted: 05/28/2009] [Indexed: 10/20/2022]
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Englot DJ, Blumenfeld H. Consciousness and epilepsy: why are complex-partial seizures complex? PROGRESS IN BRAIN RESEARCH 2009; 177:147-70. [PMID: 19818900 DOI: 10.1016/s0079-6123(09)17711-7] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Why do complex-partial seizures in temporal lobe epilepsy (TLE) cause a loss of consciousness? Abnormal function of the medial temporal lobe is expected to cause memory loss, but it is unclear why profoundly impaired consciousness is so common in temporal lobe seizures. Recent exciting advances in behavioral, electrophysiological, and neuroimaging techniques spanning both human patients and animal models may allow new insights into this old question. While behavioral automatisms are often associated with diminished consciousness during temporal lobe seizures, impaired consciousness without ictal motor activity has also been described. Some have argued that electrographic lateralization of seizure activity to the left temporal lobe is most likely to cause impaired consciousness, but the evidence remains equivocal. Other data correlates ictal consciousness in TLE with bilateral temporal lobe involvement of seizure spiking. Nevertheless, it remains unclear why bilateral temporal seizures should impair responsiveness. Recent evidence has shown that impaired consciousness during temporal lobe seizures is correlated with large-amplitude slow EEG activity and neuroimaging signal decreases in the frontal and parietal association cortices. This abnormal decreased function in the neocortex contrasts with fast polyspike activity and elevated cerebral blood flow in limbic and other subcortical structures ictally. Our laboratory has thus proposed the "network inhibition hypothesis," in which seizure activity propagates to subcortical regions necessary for cortical activation, allowing the cortex to descend into an inhibited state of unconsciousness during complex-partial temporal lobe seizures. Supporting this hypothesis, recent rat studies during partial limbic seizures have shown that behavioral arrest is associated with frontal cortical slow waves, decreased neuronal firing, and hypometabolism. Animal studies further demonstrate that cortical deactivation and behavioral changes depend on seizure spread to subcortical structures including the lateral septum. Understanding the contributions of network inhibition to impaired consciousness in TLE is an important goal, as recurrent limbic seizures often result in cortical dysfunction during and between epileptic events that adversely affects patients' quality of life.
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Affiliation(s)
- Dario J Englot
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
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