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Li W, Jiang Y, Li X, Huang H, Lei D, Li J, Zhang H, Yao D, Luo C, Gong Q, Zhou D, An D. More extensive structural damage in temporal lobe epilepsy with hippocampal sclerosis type 1. Seizure 2023; 111:130-137. [PMID: 37633152 DOI: 10.1016/j.seizure.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 08/04/2023] [Accepted: 08/06/2023] [Indexed: 08/28/2023] Open
Abstract
OBJECTIVE To explore clinical and structural differences between mesial temporal lobe epilepsy (mTLE) patients with different hippocampal sclerosis (HS) subtypes. METHODS High-resolution T1-weighted MRI and diffusion tensor imaging data were obtained in 41 refractory mTLE patients and 52 age- and sex-matched healthy controls. Postoperative histopathological examination confirmed HS type 1 in 30 patients and HS type 2 in eleven patients. Clinical features, postoperative seizure outcomes, hippocampal subfields volumes, fractional anisotropy (FA) values of white matter regions and graph theory parameters were explored and compared between the HS type 1 and HS type 2 groups. RESULTS No significant differences in clinical features and postsurgical seizure outcomes were found between the HS type 1 and type 2 groups. However, the HS type 1 group showed extra atrophy in ipsilateral parasubiculum than healthy controls and more severe atrophy in contralateral hippocampal fissure than the HS type 2 group. More extensive FA decrease were also observed in the HS type 1 group, involving ipsilateral optic radiation, superior fronto-occipital fasciculus, contralateral uncinate fasciculus, tapetum, bilateral hippocampal cingulum, corona radiata, etc. Furthermore, in spite of similar impairments in characteristic path length, global efficiency and local efficiency in two HS groups, the HS type 1 group showed additional decrease of clustering coefficient than healthy controls. CONCLUSIONS HS type 1 and 2 groups had similar clinical characteristics and postoperative seizure outcomes. More widespread neuronal cell loss in the HS type 1 group contributed to more extensive structural damage and connectivity abnormality. These results shed new light on the imaging correlates of different HS pathology.
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Affiliation(s)
- Wei Li
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China; National Clinical Research Center for Geriatrics, Department of Gerontology and Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Yuchao Jiang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, Center for Information in Medicine, School of life Science and technology, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
| | - Xiuli Li
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Huan Huang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, Center for Information in Medicine, School of life Science and technology, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
| | - Du Lei
- Huaxi MR Research Center, Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jinmei Li
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Heng Zhang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Dezhong Yao
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, Center for Information in Medicine, School of life Science and technology, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
| | - Cheng Luo
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, Center for Information in Medicine, School of life Science and technology, University of Electronic Science and Technology of China, 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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Ierusalimsky NV, Karimova ED, Samotaeva IS, Luzin RV, Zinchuk MS, Rider FK, Guekht AB. [Structural brain changes in patients with temporal lobe epilepsy and comorbid depression]. Zh Nevrol Psikhiatr Im S S Korsakova 2023; 123:83-89. [PMID: 37796072 DOI: 10.17116/jnevro202312309183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
OBJECTIVE To assess the morphological features of the brain structures in patients with temporal lobe epilepsy and comorbid depression. MATERIAL AND METHODS From 1 January 2017 to 31 December 2020, we studied 80 patients with temporal lobe epilepsy (aged 18-60 years, 38 of whom had comorbid depression) and 48 healthy subjects of comparable age. Magnetic resonance imaging (MRI) of the brain was performed using the epilepsy protocol in a scanner with a magnetic field strength of 1.5 T. Focal temporal lobe epilepsy was diagnosed by neurologists (epileptologists) specialising in epilepsy according to the International League Against Epilepsy (ILAE) classification of epilepsy. Psychiatrists assessed the presence and severity of depressive disorders by clinical interview and by participants' scores on the Beck Depression Inventory (BDI-II). MRI data were processed using FreeSurfer 6.0 software to determine volumes of subcortical structures and thicknesses of cortical structures. At the group level, analysis of covariance with Holm-Bonferroni correction was used as the statistical method. RESULTS Morphometric analysis revealed a significant decrease in the volume of the thalamus bilaterally and the brain stem and an increase in the volume of the choroid plexus in the left hemisphere, as well as a significant decrease in the thickness of the entorhinal cortex, temporal pole and isthmus of the cingulate gyrus in the left hemisphere and middle temporal gyrus and inferior temporal gyrus in the right hemisphere in patients with epilepsy compared to healthy controls. No association was found between the presence of depression and significant structural changes on MRI. CONCLUSION The data obtained suggest an effect of temporal lobe epilepsy, but not comorbid depression, on the morphology of brain structures.
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Affiliation(s)
- N V Ierusalimsky
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, Russia
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - E D Karimova
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, Russia
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - I S Samotaeva
- Institute of Higher Nervous Activity and Neurophysiology, Moscow, Russia
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - R V Luzin
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - M S Zinchuk
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - F K Rider
- Scientific and Practical Psychoneurological Center, Moscow, Russia
| | - A B Guekht
- Scientific and Practical Psychoneurological Center, Moscow, Russia
- Pirogov Russian National Research Medical University, Moscow, Russia
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Yan H, Wang X, Yu T, Ni D, Qiao L, Zhang X, Xu C, Shu W, Wang Y, Ren L. The anterior nucleus of the thalamus plays a role in the epileptic network. Ann Clin Transl Neurol 2022; 9:2010-2024. [PMID: 36334281 PMCID: PMC9735375 DOI: 10.1002/acn3.51693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 10/10/2022] [Accepted: 10/24/2022] [Indexed: 11/07/2022] Open
Abstract
OBJECTIVES We investigated both the metabolic differences and interictal/ictal discharges of the anterior nucleus of the thalamus (ANT) in patients with epilepsy to clarify the relationship between the ANT and the epileptic network. METHODS Nineteen patients with drug-resistant epilepsy who underwent stereoelectroencephalography were studied. Metabolic differences in ANT were analyzed using [18F] fluorodeoxyglucose-positron emission tomography with three-dimensional (3D) visual and quantitative analyses. Interictal and ictal discharges in the ANT were analyzed using visual and time-frequency analyses. The relationship between interictal discharge and metabolic differences was analyzed. RESULTS We found that patients with temporal lobe epilepsy (TLE) showed significant metabolic differences in bilateral ANT compared with extratemporal lobe epilepsy in 3D visual and quantitative analyses. Four types of interictal activities were recorded from the ANT: spike, high-frequency oscillation (HFO), slow-wave, and α-rhythmic activity. Spike and HFO waveforms were recorded mainly in patients with TLE. Two spike patterns were recorded: synchronous and independent. In 83.3% of patients, ANT was involved during seizures. Three seizure onset types of ANT were recorded: low-voltage fast activity, rhythmic spikes, and theta band discharge. The time interval of seizure onset between the seizure onset zone and ANT showed two patterns: immediate and delayed. INTERPRETATION ANT can receive either interictal discharges or ictal discharges which propagate from the epileptogenic zones. Independent epileptic discharges can also be recorded from the ANT in some patients. Metabolic anomalies and epileptic discharges in the ANT indicate that the ANT plays a role in the epileptic network in most patients with epilepsy, especially TLE.
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Affiliation(s)
- Hao Yan
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Xueyuan Wang
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Tao Yu
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Duanyu Ni
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Liang Qiao
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Xiaohua Zhang
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Cuiping Xu
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Wei Shu
- Department of Functional NeurosurgeryBeijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Yuping Wang
- Department of Neurology, Comprehensive Epilepsy Center of Beijing, Beijing Key Laboratory of NeuromodulationXuanwu Hospital, Capital Medical UniversityBeijingChina
| | - Liankun Ren
- Department of Neurology, Comprehensive Epilepsy Center of Beijing, Beijing Key Laboratory of NeuromodulationXuanwu Hospital, Capital Medical UniversityBeijingChina
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Khalife MR, Scott RC, Hernan AE. Mechanisms for Cognitive Impairment in Epilepsy: Moving Beyond Seizures. Front Neurol 2022; 13:878991. [PMID: 35645970 PMCID: PMC9135108 DOI: 10.3389/fneur.2022.878991] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/19/2022] [Indexed: 11/13/2022] Open
Abstract
There has been a major emphasis on defining the role of seizures in the causation of cognitive impairments like memory deficits in epilepsy. Here we focus on an alternative hypothesis behind these deficits, emphasizing the mechanisms of information processing underlying healthy cognition characterized as rate, temporal and population coding. We discuss the role of the underlying etiology of epilepsy in altering neural networks thereby leading to both the propensity for seizures and the associated cognitive impairments. In addition, we address potential treatments that can recover the network function in the context of a diseased brain, thereby improving both seizure and cognitive outcomes simultaneously. This review shows the importance of moving beyond seizures and approaching the deficits from a system-level perspective with the guidance of network neuroscience.
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Affiliation(s)
- Mohamed R. Khalife
- Division of Neuroscience, Nemours Children's Health, Wilmington, DE, United States
- Psychological and Brain Sciences, University of Delaware, Newark, DE, United States
| | - Rod C. Scott
- Division of Neuroscience, Nemours Children's Health, Wilmington, DE, United States
- Psychological and Brain Sciences, University of Delaware, Newark, DE, United States
- Institute of Child Health, Neurosciences Unit University College London, London, United Kingdom
| | - Amanda E. Hernan
- Division of Neuroscience, Nemours Children's Health, Wilmington, DE, United States
- Psychological and Brain Sciences, University of Delaware, Newark, DE, United States
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Middlebrooks EH, He X, Grewal SS, Keller SS. Neuroimaging and thalamic connectomics in epilepsy neuromodulation. Epilepsy Res 2022; 182:106916. [PMID: 35367691 DOI: 10.1016/j.eplepsyres.2022.106916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/05/2022] [Accepted: 03/27/2022] [Indexed: 11/03/2022]
Abstract
Neuromodulation is an increasingly utilized therapy for the treatment of people with drug-resistant epilepsy. To date, the most common and effective target has been the thalamus, which is known to play a key role in multiple forms of epilepsy. Neuroimaging has facilitated rapid developments in the understanding of functional targets, surgical and programming techniques, and the effects of thalamic stimulation. In this review, the role of neuroimaging in neuromodulation is explored. First, the structural and functional changes of the thalamus in common epilepsy syndromes are discussed as the rationale for neuromodulation of the thalamus. Next, methods for imaging different thalamic nuclei are presented, as well as rationale for the need of direct surgical targeting rather than reliance on traditional stereotactic coordinates. Lastly, we discuss the potential role of neuroimaging in assessing the effects of thalamic stimulation and as a potential biomarker for neuromodulation outcomes.
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Affiliation(s)
- Erik H Middlebrooks
- Department of Radiology, Mayo Clinic, Jacksonville, FL, USA; Department of Neurosurgery, Mayo Clinic, Jacksonville, FL, USA.
| | - Xiaosong He
- Department of Psychology, University of Science and Technology of China, Hefei, Anhui, China
| | | | - Simon S Keller
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, UK
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6
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Prediction of seizure outcome following temporal lobectomy: a magnetoencephalography-based graph theory approach". Seizure 2022; 97:73-81. [DOI: 10.1016/j.seizure.2022.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/12/2022] [Accepted: 03/15/2022] [Indexed: 11/22/2022] Open
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Tung H, Pan SY, Lan TH, Lin YY, Peng SJ. Characterization of Hippocampal-Thalamic-Cortical Morphometric Reorganization in Temporal Lobe Epilepsy. Front Neurol 2022; 12:810186. [PMID: 35222230 PMCID: PMC8866816 DOI: 10.3389/fneur.2021.810186] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 12/31/2021] [Indexed: 11/13/2022] Open
Abstract
IntroductionBrain cortico-subcortical connectivity has been investigated in epilepsy using the functional MRI (MRI). Although structural images cannot demonstrate dynamic changes, they provide higher spatial resolution, which allows exploration of the organization of brain in greater detail.MethodsWe used high-resolution brain MRI to study the hippocampal-thalamic-cortical networks in temporal lobe epilepsy (TLE) using a volume-based morphometric method. We enrolled 22 right-TLE, 33 left-TLE, and 28 age/gender-matched controls retrospectively. FreeSurfer software was used for the thalamus segmentation.ResultsAmong the 50 subfields, ipsilateral anterior, lateral, and parts of the intralaminar and medial nuclei, as well as the contralateral parts of lateral nuclei had significant volume loss in both TLE. The anteroventral nucleus was most vulnerable. Most thalamic subfields were susceptible to seizure burden, especially the left-TLE. SPM12 was used to conduct an analysis of the gray matter density (GMD) maps. Decreased extratemporal GMD occurred bilaterally. Both TLE demonstrated significant GMD loss over the ipsilateral inferior frontal gyrus, precentral gyrus, and medial orbital cortices.SignificanceThalamic subfield atrophy was related to the ipsilateral inferior frontal GMD changes, which presented positively in left-TLE and negatively in right-TLE. These findings suggest prefrontal-thalamo-hippocampal network disruption in TLE.
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Affiliation(s)
- Hsin Tung
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Center of Faculty Development, Taichung Veterans General Hospital, Taichung, Taiwan
- Division of Epilepsy, Neurological Institute, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Szu-Yen Pan
- Department of Neurosurgery, Neurological Institute, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Tsuo-Hung Lan
- Tsaotun Psychiatric Center, Ministry of Health and Welfare, Nantou, Taiwan
- Department of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Center for Neuropsychiatric Research, National Health Research Institutes, Zhunan, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yung-Yang Lin
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Department of Critical Care Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
- Institute of Brain Science, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Syu-Jyun Peng
- Professional Master Program in Artificial Intelligence in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- *Correspondence: Syu-Jyun Peng
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Gregg NM, Sladky V, Nejedly P, Mivalt F, Kim I, Balzekas I, Sturges BK, Crowe C, Patterson EE, Van Gompel JJ, Lundstrom BN, Leyde K, Denison TJ, Brinkmann BH, Kremen V, Worrell GA. Thalamic deep brain stimulation modulates cycles of seizure risk in epilepsy. Sci Rep 2021; 11:24250. [PMID: 34930926 PMCID: PMC8688461 DOI: 10.1038/s41598-021-03555-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 12/03/2021] [Indexed: 11/30/2022] Open
Abstract
Chronic brain recordings suggest that seizure risk is not uniform, but rather varies systematically relative to daily (circadian) and multiday (multidien) cycles. Here, one human and seven dogs with naturally occurring epilepsy had continuous intracranial EEG (median 298 days) using novel implantable sensing and stimulation devices. Two pet dogs and the human subject received concurrent thalamic deep brain stimulation (DBS) over multiple months. All subjects had circadian and multiday cycles in the rate of interictal epileptiform spikes (IES). There was seizure phase locking to circadian and multiday IES cycles in five and seven out of eight subjects, respectively. Thalamic DBS modified circadian (all 3 subjects) and multiday (analysis limited to the human participant) IES cycles. DBS modified seizure clustering and circadian phase locking in the human subject. Multiscale cycles in brain excitability and seizure risk are features of human and canine epilepsy and are modifiable by thalamic DBS.
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Affiliation(s)
- Nicholas M Gregg
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA.
| | - Vladimir Sladky
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
- International Clinical Research Center, St. Anne's University Hospital, 656 91, Brno, Czech Republic
- Faculty of Biomedical Engineering, Czech Technical University in Prague, 272 01, Kladno, Czech Republic
| | - Petr Nejedly
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
- International Clinical Research Center, St. Anne's University Hospital, 656 91, Brno, Czech Republic
| | - Filip Mivalt
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
- International Clinical Research Center, St. Anne's University Hospital, 656 91, Brno, Czech Republic
- Department of Biomedical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, 616 00, Brno, Czech Republic
| | - Inyong Kim
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
| | - Irena Balzekas
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
- Mayo Clinic School of Medicine and the Medical Scientist Training Program, Mayo Clinic, Rochester, MN, 55905, USA
| | - Beverly K Sturges
- Department of Veterinary Clinical Sciences, University of California, Davis, CA, 95616, USA
| | - Chelsea Crowe
- Department of Veterinary Clinical Sciences, University of California, Davis, CA, 95616, USA
| | - Edward E Patterson
- Department of Veterinary Clinical Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN, 55108, USA
| | | | - Brian N Lundstrom
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
| | - Kent Leyde
- Cadence Neuroscience, Seattle, WA, 98052, USA
| | - Timothy J Denison
- Institute for Biomedical Engineering, Oxford University, Oxford, OX3 7DQ, UK
| | - Benjamin H Brinkmann
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
| | - Vaclav Kremen
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA
- Czech Institute of Informatics, Robotics, and Cybernetics, Czech Technical University in Prague, 160 00, Prague, Czech Republic
| | - Gregory A Worrell
- Department of Neurology, Bioelectronics Neurophysiology and Engineering Laboratory, Mayo Clinic, Rochester, MN, 55905, USA.
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Dolleman-van der Weel MJ, Witter MP. The thalamic midline nucleus reuniens: potential relevance for schizophrenia and epilepsy. Neurosci Biobehav Rev 2020; 119:422-439. [PMID: 33031816 DOI: 10.1016/j.neubiorev.2020.09.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 09/03/2020] [Accepted: 09/28/2020] [Indexed: 01/08/2023]
Abstract
Anatomical, electrophysiological and behavioral studies in rodents have shown that the thalamic midline nucleus reuniens (RE) is a crucial link in the communication between hippocampal formation (HIP, i.e., CA1, subiculum) and medial prefrontal cortex (mPFC), important structures for cognitive and executive functions. A common feature in neurodevelopmental and neurodegenerative brain diseases is a dysfunctional connectivity/communication between HIP and mPFC, and disturbances in the cognitive domain. Therefore, it is assumed that aberrant functioning of RE may contribute to behavioral/cognitive impairments in brain diseases characterized by cortico-thalamo-hippocampal circuit dysfunctions. In the human brain the connections of RE are largely unknown. Yet, recent studies have found important similarities in the functional connectivity of HIP-mPFC-RE in humans and rodents, making cautious extrapolating experimental findings from animal models to humans justifiable. The focus of this review is on a potential involvement of RE in schizophrenia and epilepsy.
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Affiliation(s)
- M J Dolleman-van der Weel
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU Norwegian University of Science and Technology, Trondheim NO-7491, Norway.
| | - M P Witter
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU Norwegian University of Science and Technology, Trondheim NO-7491, Norway.
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Caciagli L, Allen LA, He X, Trimmel K, Vos SB, Centeno M, Galovic M, Sidhu MK, Thompson PJ, Bassett DS, Winston GP, Duncan JS, Koepp MJ, Sperling MR. Thalamus and focal to bilateral seizures: A multiscale cognitive imaging study. Neurology 2020; 95:e2427-e2441. [PMID: 32847951 PMCID: PMC7682917 DOI: 10.1212/wnl.0000000000010645] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 06/01/2020] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVE To investigate the functional correlates of recurrent secondarily generalized seizures in temporal lobe epilepsy (TLE) using task-based fMRI as a framework to test for epilepsy-specific network rearrangements. Because the thalamus modulates propagation of temporal lobe onset seizures and promotes cortical synchronization during cognition, we hypothesized that occurrence of secondarily generalized seizures, i.e., focal to bilateral tonic-clonic seizures (FBTCS), would relate to thalamic dysfunction, altered connectivity, and whole-brain network centrality. METHODS FBTCS occur in a third of patients with TLE and are a major determinant of disease severity. In this cross-sectional study, we analyzed 113 patients with drug-resistant TLE (55 left/58 right), who performed a verbal fluency fMRI task that elicited robust thalamic activation. Thirty-three patients (29%) had experienced at least one FBTCS in the year preceding the investigation. We compared patients with TLE-FBTCS to those without FBTCS via a multiscale approach, entailing analysis of statistical parametric mapping (SPM) 12-derived measures of activation, task-modulated thalamic functional connectivity (psychophysiologic interaction), and graph-theoretical metrics of centrality. RESULTS Individuals with TLE-FBTCS had less task-related activation of bilateral thalamus, with left-sided emphasis, and left hippocampus than those without FBTCS. In TLE-FBTCS, we also found greater task-related thalamotemporal and thalamomotor connectivity, and higher thalamic degree and betweenness centrality. Receiver operating characteristic curves, based on a combined thalamic functional marker, accurately discriminated individuals with and without FBTCS. CONCLUSIONS In TLE-FBTCS, impaired task-related thalamic recruitment coexists with enhanced thalamotemporal connectivity and whole-brain thalamic network embedding. Altered thalamic functional profiles are proposed as imaging biomarkers of active secondary generalization.
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Affiliation(s)
- Lorenzo Caciagli
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA.
| | - Luke A Allen
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Xiaosong He
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Karin Trimmel
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Sjoerd B Vos
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Maria Centeno
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Marian Galovic
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Meneka K Sidhu
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Pamela J Thompson
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Danielle S Bassett
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Gavin P Winston
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - John S Duncan
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Matthias J Koepp
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
| | - Michael R Sperling
- From the Department of Clinical and Experimental Epilepsy (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.) and Neuroradiological Academic Unit (S.B.V.), UCL Queen Square Institute of Neurology, London; MRI Unit (L.C., L.A.A., K.T., S.B.V., M.C., M.G., M.K.S., P.J.T., G.P.W., J.S.D., M.J.K.), Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK; Departments of Bioengineering (L.C., X.H., D.S.B.), Physics and Astronomy (D.S.B.), Electrical and Systems Engineering (D.S.B.), Neurology (D.S.B.), and Psychiatry (D.S.B.), University of Pennsylvania, Philadelphia; Department of Neurology (K.T.), Medical University of Vienna, Austria; Centre for Medical Image Computing (S.B.V.), University College London, UK; Department of Neurology (M.G.), University Hospital Zurich, Switzerland; Santa Fe Institute (D.S.B.), NM; Department of Medicine, Division of Neurology (G.P.W.), Queen's University, Kingston, Canada; and Department of Neurology (M.R.S.), Thomas Jefferson University, Philadelphia, PA
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11
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Wu D, Chang F, Peng D, Xie S, Li X, Zheng W. The morphological characteristics of hippocampus and thalamus in mesial temporal lobe epilepsy. BMC Neurol 2020; 20:235. [PMID: 32513122 PMCID: PMC7282186 DOI: 10.1186/s12883-020-01817-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 06/02/2020] [Indexed: 11/16/2022] Open
Abstract
Background Mesial temporal lobe epilepsy (MTLE) is the most common form of focal epilepsy, which is frequently characterized by hippocampal sclerosis (HS). Accumulating studies have suggested widespread cortico-cortical connections related to MTLE. The role of subcortical structures involved in general epilepsy has been extensively investigated, but it is still limited in MTLE. Our purpose was to determine the specific morphological correlation between sclerotic hippocampal and thalamic sub-regions, using quantitative analysis, in MTLE. Methods In this study, 23 MTLE patients with unilateral hippocampal sclerosis and 24 healthy controls were examined with three-dimensional T1 MRI. Volume quantitative analysis in the hippocampus and thalamus was conducted and group-related volumetric difference was assessed. Moreover, vertex analysis was further performed using automated software to delineate detailed morphological patterns of the hippocampus and thalamus. The correlation was used to examine whether there is a relationship between volume changes of two subcortical structures and clinical characteristics. Results The patients had a significant volume decrease in the sclerotic hippocampus (p < 0.001). Compared to controls, obvious atrophic patterns were observed in the bilateral hippocampus in MTLE (p < 0.05). Only small patches of shrinkage were noted in the bilateral thalamus (p < 0.05). Moreover, the volume change of the hippocampus had a significant positive correlation with that of the thalamus (P < 0.001). Intriguingly, volume changes of the hippocampus and thalamus were correlated with the duration of epilepsy (hippocampus: P = 0.024; thalamus: P = 0.022). However, only volume changes of thalamus possibly differentiated between two prognostic groups in patients (P = 0.026). Conclusions We demonstrated the morphological characteristics of the hippocampus and thalamus in MTLE, providing new insights into the interrelated mechanisms between the hippocampus and thalamus, which have potential clinical significance for refining neuromodulated targets.
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Affiliation(s)
- Dongyan Wu
- Department of Neurology, China-Japan Friendship Hospital, Beijing, 100029, China.
| | - Feiyan Chang
- Department of Radiology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Dantao Peng
- Department of Neurology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Sheng Xie
- Department of Radiology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Xiaoxuan Li
- Department of Neurology, China-Japan Friendship Hospital, Beijing, 100029, China
| | - Wenjing Zheng
- Department of Neurology, China-Japan Friendship Hospital, Beijing, 100029, China
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12
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Guo W, Koo BB, Kim JH, Bhadelia RA, Seo DW, Hong SB, Joo EY, Lee S, Lee JI, Cho KR, Shon YM. Defining the optimal target for anterior thalamic deep brain stimulation in patients with drug-refractory epilepsy. J Neurosurg 2020; 134:1054-1063. [PMID: 32384279 DOI: 10.3171/2020.2.jns193226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 02/24/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE The anterior thalamic nucleus (ATN) is a common target for deep brain stimulation (DBS) for the treatment of drug-refractory epilepsy. However, no atlas-based optimal DBS (active contacts) target within the ATN has been definitively identified. The object of this retrospective study was to analyze the relationship between the active contact location and seizure reduction to establish an atlas-based optimal target for ATN DBS. METHODS From among 25 patients who had undergone ATN DBS surgery for drug-resistant epilepsy between 2016 and 2018, those who had follow-up evaluations for more than 1 year were eligible for study inclusion. After an initial stimulation period of 6 months, patients were classified as responsive (≥ 50% median decrease in seizure frequency) or nonresponsive (< 50% median decrease in seizure frequency) to treatment. Stimulation parameters and/or active contact positions were adjusted in nonresponsive patients, and their responsiveness was monitored for at least 1 year. Postoperative CT scans were coregistered nonlinearly with preoperative MR images to determine the center coordinate and atlas-based anatomical localizations of all active contacts in the Montreal Neurological Institute (MNI) 152 space. RESULTS Nineteen patients with drug-resistant epilepsy were followed up for at least a year following bilateral DBS electrode implantation targeting the ATN. Active contacts located more adjacent to the center of gravity of the anterior half of the ATN volume, defined as the anterior center (AC), were associated with greater seizure reduction than those not in this location. Intriguingly, the initially nonresponsive patients could end up with much improved seizure reduction by adjusting the active contacts closer to the AC at the final postoperative follow-up. CONCLUSIONS Patients with stimulation targeting the AC may have a favorable seizure reduction. Moreover, the authors were able to obtain additional good outcomes after electrode repositioning in the initially nonresponsive patients. Purposeful and strategic trajectory planning to target this optimal region may predict favorable outcomes of ATN DBS.
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Affiliation(s)
- Wendy Guo
- 1Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts
| | - Bang-Bon Koo
- 1Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts
| | - Jae-Hun Kim
- 2Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Rafeeque A Bhadelia
- 3Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Dae-Won Seo
- 4Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul
| | - Seung Bong Hong
- 4Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul
| | - Eun Yeon Joo
- 4Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul
| | - Seunghoon Lee
- 5Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul; and
| | - Jung-Il Lee
- 5Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul; and
| | - Kyung Rae Cho
- 5Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul; and
| | - Young-Min Shon
- 4Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul.,6Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea
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13
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Whelan CD, Altmann A, Botía JA, Jahanshad N, Hibar DP, Absil J, Alhusaini S, Alvim MKM, Auvinen P, Bartolini E, Bergo FPG, Bernardes T, Blackmon K, Braga B, Caligiuri ME, Calvo A, Carr SJ, Chen J, Chen S, Cherubini A, David P, Domin M, Foley S, França W, Haaker G, Isaev D, Keller SS, Kotikalapudi R, Kowalczyk MA, Kuzniecky R, Langner S, Lenge M, Leyden KM, Liu M, Loi RQ, Martin P, Mascalchi M, Morita ME, Pariente JC, Rodríguez-Cruces R, Rummel C, Saavalainen T, Semmelroch MK, Severino M, Thomas RH, Tondelli M, Tortora D, Vaudano AE, Vivash L, von Podewils F, Wagner J, Weber B, Yao Y, Yasuda CL, Zhang G, Bargalló N, Bender B, Bernasconi N, Bernasconi A, Bernhardt BC, Blümcke I, Carlson C, Cavalleri GL, Cendes F, Concha L, Delanty N, Depondt C, Devinsky O, Doherty CP, Focke NK, Gambardella A, Guerrini R, Hamandi K, Jackson GD, Kälviäinen R, Kochunov P, Kwan P, Labate A, McDonald CR, Meletti S, O'Brien TJ, Ourselin S, Richardson MP, Striano P, Thesen T, Wiest R, Zhang J, Vezzani A, Ryten M, Thompson PM, Sisodiya SM. Structural brain abnormalities in the common epilepsies assessed in a worldwide ENIGMA study. Brain 2019; 141:391-408. [PMID: 29365066 PMCID: PMC5837616 DOI: 10.1093/brain/awx341] [Citation(s) in RCA: 287] [Impact Index Per Article: 57.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Accepted: 10/24/2017] [Indexed: 12/02/2022] Open
Abstract
Progressive functional decline in the epilepsies is largely unexplained. We formed the ENIGMA-Epilepsy consortium to understand factors that influence brain measures in epilepsy, pooling data from 24 research centres in 14 countries across Europe, North and South America, Asia, and Australia. Structural brain measures were extracted from MRI brain scans across 2149 individuals with epilepsy, divided into four epilepsy subgroups including idiopathic generalized epilepsies (n =367), mesial temporal lobe epilepsies with hippocampal sclerosis (MTLE; left, n = 415; right, n = 339), and all other epilepsies in aggregate (n = 1026), and compared to 1727 matched healthy controls. We ranked brain structures in order of greatest differences between patients and controls, by meta-analysing effect sizes across 16 subcortical and 68 cortical brain regions. We also tested effects of duration of disease, age at onset, and age-by-diagnosis interactions on structural measures. We observed widespread patterns of altered subcortical volume and reduced cortical grey matter thickness. Compared to controls, all epilepsy groups showed lower volume in the right thalamus (Cohen’s d = −0.24 to −0.73; P < 1.49 × 10−4), and lower thickness in the precentral gyri bilaterally (d = −0.34 to −0.52; P < 4.31 × 10−6). Both MTLE subgroups showed profound volume reduction in the ipsilateral hippocampus (d = −1.73 to −1.91, P < 1.4 × 10−19), and lower thickness in extrahippocampal cortical regions, including the precentral and paracentral gyri, compared to controls (d = −0.36 to −0.52; P < 1.49 × 10−4). Thickness differences of the ipsilateral temporopolar, parahippocampal, entorhinal, and fusiform gyri, contralateral pars triangularis, and bilateral precuneus, superior frontal and caudal middle frontal gyri were observed in left, but not right, MTLE (d = −0.29 to −0.54; P < 1.49 × 10−4). Contrastingly, thickness differences of the ipsilateral pars opercularis, and contralateral transverse temporal gyrus, were observed in right, but not left, MTLE (d = −0.27 to −0.51; P < 1.49 × 10−4). Lower subcortical volume and cortical thickness associated with a longer duration of epilepsy in the all-epilepsies, all-other-epilepsies, and right MTLE groups (beta, b < −0.0018; P < 1.49 × 10−4). In the largest neuroimaging study of epilepsy to date, we provide information on the common epilepsies that could not be realistically acquired in any other way. Our study provides a robust ranking of brain measures that can be further targeted for study in genetic and neuropathological studies. This worldwide initiative identifies patterns of shared grey matter reduction across epilepsy syndromes, and distinctive abnormalities between epilepsy syndromes, which inform our understanding of epilepsy as a network disorder, and indicate that certain epilepsy syndromes involve more widespread structural compromise than previously assumed.
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Affiliation(s)
- Christopher D Whelan
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA.,Department of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Andre Altmann
- Translational Imaging Group, Centre for Medical Image Computing, University College London, London, UK
| | - Juan A Botía
- Reta Lila Weston Institute and Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Neda Jahanshad
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA
| | - Derrek P Hibar
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA
| | - Julie Absil
- Department of Radiology, Hôpital Erasme, Universite Libre de Bruxelles, Brussels 1070, Belgium
| | - Saud Alhusaini
- Department of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland.,Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Marina K M Alvim
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Pia Auvinen
- Epilepsy Center, Department of Neurology, Kuopio University, Kuopio, Finland.,Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland
| | - Emanuele Bartolini
- Pediatric Neurology Unit, Children's Hospital A. Meyer-University of Florence, Italy.,IRCCS Stella Maris Foundation, Pisa, Italy
| | - Felipe P G Bergo
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Tauana Bernardes
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Karen Blackmon
- Comprehensive Epilepsy Center, Department of Neurology, New York University School of Medicine, New York, USA.,Department of Physiology, Neuroscience and Behavioral Science, St. George's University, Grenada, West Indies
| | - Barbara Braga
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Maria Eugenia Caligiuri
- Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Catanzaro, Italy
| | - Anna Calvo
- Magnetic Resonance Image Core Facility, IDIBAPS, Barcelona, Spain
| | - Sarah J Carr
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK
| | - Jian Chen
- Department of Computer Science and Engineering, The Ohio State University, USA
| | - Shuai Chen
- Cognitive Science Department, Xiamen University, Xiamen, China.,Fujian Key Laboratory of the Brain-like Intelligent Systems, China
| | - Andrea Cherubini
- Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Catanzaro, Italy
| | - Philippe David
- Department of Radiology, Hôpital Erasme, Universite Libre de Bruxelles, Brussels 1070, Belgium
| | - Martin Domin
- Functional Imaging Unit, Institute of Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Greifswald, Germany
| | - Sonya Foley
- Cardiff University Brain Research Imaging Centre, School of Psychology, Wales, UK
| | - Wendy França
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Gerrit Haaker
- Department of Neurosurgery, University Hospital, Freiburg, Germany.,Department of Neuropathology, University Hospital Erlangen, Germany
| | - Dmitry Isaev
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA
| | - Simon S Keller
- Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, UK
| | - Raviteja Kotikalapudi
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Department of Diagnostic and Interventional Neuroradiology, University of Tübingen, Tübingen, Germany
| | - Magdalena A Kowalczyk
- The Florey Institute of Neuroscience and Mental Health, Austin Campus, Melbourne, VIC, Australia
| | - Ruben Kuzniecky
- Comprehensive Epilepsy Center, Department of Neurology, New York University School of Medicine, New York, USA
| | - Soenke Langner
- Functional Imaging Unit, Institute of Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, Greifswald, Germany
| | - Matteo Lenge
- Pediatric Neurology Unit, Children's Hospital A. Meyer-University of Florence, Italy
| | - Kelly M Leyden
- Multimodal Imaging Laboratory, University of California San Diego, San Diego, California, USA.,Department of Psychiatry, University of California San Diego, San Diego, California, USA
| | - Min Liu
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, Mcgill University, Montreal, Quebec, Canada
| | - Richard Q Loi
- Multimodal Imaging Laboratory, University of California San Diego, San Diego, California, USA.,Department of Psychiatry, University of California San Diego, San Diego, California, USA
| | - Pascal Martin
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Mario Mascalchi
- Neuroradiology Unit, Children's Hospital A. Meyer, Florence, Italy.,"Mario Serio" Department of Experimental and Clinical Biomedical Sciences, University of Florence, Italy
| | - Marcia E Morita
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Jose C Pariente
- Magnetic Resonance Image Core Facility, IDIBAPS, Barcelona, Spain
| | - Raul Rodríguez-Cruces
- Instituto de Neurobiología, Universidad Nacional Autónoma de México. Querétaro, Querétaro, México
| | - Christian Rummel
- Support Center for Advanced Neuroimaging (SCAN), University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Taavi Saavalainen
- Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland.,Central Finland Central Hospital, Medical Imaging Unit, Jyväskylä, Finland
| | - Mira K Semmelroch
- The Florey Institute of Neuroscience and Mental Health, Austin Campus, Melbourne, VIC, Australia
| | - Mariasavina Severino
- Neuroradiology Unit, Department of Head and Neck and Neurosciences, Istituto Giannina Gaslini, Genova, Italy
| | - Rhys H Thomas
- Institute of Psychological Medicine and Clinical Neurosciences, Hadyn Ellis Building, Maindy Road, Cardiff, UK.,Department of Neurology, University Hospital of Wales, Cardiff, UK
| | - Manuela Tondelli
- Department of Biomedical, Metabolic, and Neural Science, University of Modena and Reggio Emilia, NOCSE Hospital, Modena, Italy
| | - Domenico Tortora
- Neuroradiology Unit, Department of Head and Neck and Neurosciences, Istituto Giannina Gaslini, Genova, Italy
| | - Anna Elisabetta Vaudano
- Department of Biomedical, Metabolic, and Neural Science, University of Modena and Reggio Emilia, NOCSE Hospital, Modena, Italy
| | - Lucy Vivash
- Melbourne Brain Centre, Department of Medicine, University of Melbourne, Parkville, VIC, 3052, Australia.,Department of Neurology, Royal Melbourne Hospital, Parkville, 3050, Australia
| | - Felix von Podewils
- Department of Neurology, University Medicine Greifswald, Greifswald, Germany
| | - Jan Wagner
- Department of Epileptology, University Hospital Bonn, Bonn, Germany.,Department of Neurology, Philips University of Marburg, Marburg Germany
| | - Bernd Weber
- Department of Epileptology, University Hospital Bonn, Bonn, Germany.,Department of Neurocognition / Imaging, Life&Brain Research Centre, Bonn, Germany
| | - Yi Yao
- The Affiliated Chenggong Hospital of Xiamen University, Xiamen, China
| | | | - Guohao Zhang
- Department of Computer Science and Electrical Engineering, University of Maryland, Baltimore County, USA
| | - Nuria Bargalló
- Magnetic Resonance Image Core Facility, IDIBAPS, Barcelona, Spain.,Centre de Diagnostic Per la Imatge (CDIC), Hospital Clinic, Barcelona, Spain
| | - Benjamin Bender
- Department of Diagnostic and Interventional Neuroradiology, University of Tübingen, Tübingen, Germany
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, Mcgill University, Montreal, Quebec, Canada
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, Mcgill University, Montreal, Quebec, Canada
| | - Boris C Bernhardt
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, Mcgill University, Montreal, Quebec, Canada.,Multimodal Imaging and Connectome Analysis Lab, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Germany
| | - Chad Carlson
- Comprehensive Epilepsy Center, Department of Neurology, New York University School of Medicine, New York, USA.,Medical College of Wisconsin, Department of Neurology, Milwaukee, WI, USA
| | - Gianpiero L Cavalleri
- Department of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland.,FutureNeuro Research Centre, RCSI, Dublin, Ireland
| | - Fernando Cendes
- Department of Neurology, University of Campinas, Campinas, Brazil
| | - Luis Concha
- Instituto de Neurobiología, Universidad Nacional Autónoma de México. Querétaro, Querétaro, México
| | - Norman Delanty
- Department of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland.,FutureNeuro Research Centre, RCSI, Dublin, Ireland.,Division of Neurology, Beaumont Hospital, Dublin 9, Ireland
| | - Chantal Depondt
- Department of Neurology, Hôpital Erasme, Universite Libre de Bruxelles, Brussels 1070, Belgium
| | - Orrin Devinsky
- Comprehensive Epilepsy Center, Department of Neurology, New York University School of Medicine, New York, USA
| | - Colin P Doherty
- FutureNeuro Research Centre, RCSI, Dublin, Ireland.,Neurology Department, St. James's Hospital, Dublin 8, Ireland
| | - Niels K Focke
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Department of Clinical Neurophysiology, University Medicine Göttingen, Göttingen, Germany
| | - Antonio Gambardella
- Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Catanzaro, Italy.,Institute of Neurology, University "Magna Græcia", Catanzaro, Italy
| | - Renzo Guerrini
- Pediatric Neurology Unit, Children's Hospital A. Meyer-University of Florence, Italy.,IRCCS Stella Maris Foundation, Pisa, Italy
| | - Khalid Hamandi
- Institute of Psychological Medicine and Clinical Neurosciences, Hadyn Ellis Building, Maindy Road, Cardiff, UK.,Department of Neurology, University Hospital of Wales, Cardiff, UK
| | - Graeme D Jackson
- The Florey Institute of Neuroscience and Mental Health, Austin Campus, Melbourne, VIC, Australia.,Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Reetta Kälviäinen
- Epilepsy Center, Department of Neurology, Kuopio University, Kuopio, Finland.,Institute of Clinical Medicine, Neurology, University of Eastern Finland, Kuopio, Finland
| | - Peter Kochunov
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Maryland, USA
| | - Patrick Kwan
- Department of Neurology, Royal Melbourne Hospital, Parkville, 3050, Australia
| | - Angelo Labate
- Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Catanzaro, Italy.,Institute of Neurology, University "Magna Græcia", Catanzaro, Italy
| | - Carrie R McDonald
- Multimodal Imaging Laboratory, University of California San Diego, San Diego, California, USA.,Department of Psychiatry, University of California San Diego, San Diego, California, USA
| | - Stefano Meletti
- Department of Biomedical, Metabolic, and Neural Science, University of Modena and Reggio Emilia, NOCSE Hospital, Modena, Italy
| | - Terence J O'Brien
- Department of Neurology, Royal Melbourne Hospital, Parkville, 3050, Australia.,Department of Medicine, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Sebastien Ourselin
- Translational Imaging Group, Centre for Medical Image Computing, University College London, London, UK
| | - Mark P Richardson
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, UK.,Department of Neurology, King's College Hospital, London, UK
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genova, Italy
| | - Thomas Thesen
- Comprehensive Epilepsy Center, Department of Neurology, New York University School of Medicine, New York, USA.,Department of Physiology, Neuroscience and Behavioral Science, St. George's University, Grenada, West Indies
| | - Roland Wiest
- Support Center for Advanced Neuroimaging (SCAN), University Institute for Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Bern, Switzerland
| | - Junsong Zhang
- Cognitive Science Department, Xiamen University, Xiamen, China.,Fujian Key Laboratory of the Brain-like Intelligent Systems, China
| | - Annamaria Vezzani
- Dept of Neuroscience, Mario Negri Institute for Pharmacological Research, Via G. La Masa 19, 20156 Milano, Italy
| | - Mina Ryten
- Reta Lila Weston Institute and Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3BG, UK.,Department of Medical and Molecular Genetics, King's College London, London SE1 9RT, UK
| | - Paul M Thompson
- Imaging Genetics Center, Mark and Mary Stevens Neuroimaging and Informatics Institute, University of Southern California, Los Angeles, California, USA
| | - Sanjay M Sisodiya
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK.,Chalfont Centre for Epilepsy, Bucks, UK
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14
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Kuhn T, Gullett JM, Boutzoukas AE, Bohsali A, Mareci TH, FitzGerald DB, Carney PR, Bauer RM. Temporal lobe epilepsy affects spatial organization of entorhinal cortex connectivity. Epilepsy Behav 2018; 88:87-95. [PMID: 30243111 PMCID: PMC6294293 DOI: 10.1016/j.yebeh.2018.06.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 06/18/2018] [Accepted: 06/20/2018] [Indexed: 12/15/2022]
Abstract
Evidence for structural connectivity patterns within the medial temporal lobe derives primarily from postmortem histological studies. In humans and nonhuman primates, the parahippocampal gyrus (PHg) is subdivided into parahippocampal (PHc) and perirhinal (PRc) cortices, which receive input from distinct cortical networks. Likewise, their efferent projections to the entorhinal cortex (ERc) are distinct. The PHc projects primarily to the medial ERc (M-ERc). The PRc projects primarily to the lateral portion of the ERc (L-ERc). Both M-ERc and L-ERc, via the perforant pathway, project to the dentate gyrus and hippocampal (HC) subfields. Until recently, these neural circuits could not be visualized in vivo. Diffusion tensor imaging algorithms have been developed to segment gray matter structures based on probabilistic connectivity patterns. However, these algorithms have not yet been applied to investigate connectivity in the temporal lobe or changes in connectivity architecture related to disease processes. In this study, this segmentation procedure was used to classify ERc gray matter based on PRc, ERc, and HC connectivity patterns in 7 patients with temporal lobe epilepsy (TLE) without hippocampal sclerosis (mean age, 14.86 ± 3.34 years) and 7 healthy controls (mean age, 23.86 ± 2.97 years). Within samples paired t-tests allowed for comparison of ERc connectivity between epileptogenic and contralateral hemispheres. In healthy controls, there were no significant within-group differences in surface area, volume, or cluster number of ERc connectivity-defined regions (CDR). Likewise, in line with histology results, ERc CDR in the control group were well-organized, uniform, and segregated via PRc/PHc afferent and HC efferent connections. Conversely, in TLE, there were significantly more PRc and HC CDR clusters in the epileptogenic than the contralateral hemisphere. The surface area of the PRc CDR was greater, and that of the HC CDRs was smaller, in the epileptogenic hemisphere as well. Further, there was no clear delineation between M-ERc and L-ERc connectivity with PRc, PHc or HC in TLE. These results suggest a breakdown of the spatial organization of PHg-ERc-HC connectivity in TLE. Whether this breakdown is the cause or result of epileptic activity remains an exciting research question.
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Affiliation(s)
- Taylor Kuhn
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States of America; Department of Physical Therapy, University of Florida, Gainesville, FL, United States of America.
| | - Joseph M Gullett
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States of America; Department of VA Brain Rehabilitation Research Center, Malcolm Randall VA Center Gainesville, FL, United States of America
| | - Angelique E Boutzoukas
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States of America
| | - Anastasia Bohsali
- Department of Neurology, University of Florida, Gainesville, FL, United States of America
| | - Thomas H Mareci
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, United States of America
| | - David B FitzGerald
- Department of VA Brain Rehabilitation Research Center, Malcolm Randall VA Center Gainesville, FL, United States of America
| | - Paul R Carney
- Department of Pediatrics, University of Florida, Gainesville, FL, United States of America; Department of Neurology, University of Florida, Gainesville, FL, United States of America; Department of Neuroscience, University of Florida, Gainesville, FL, United States of America; J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America; B.J. and Eve Wilder Epilepsy Center Excellence, University of Florida, Gainesville, FL, United States of America
| | - Russell M Bauer
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, United States of America; Department of VA Brain Rehabilitation Research Center, Malcolm Randall VA Center Gainesville, FL, United States of America
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15
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Wu Q, Zhao CW, Long Z, Xiao B, Feng L. Anatomy Based Networks and Topology Alteration in Seizure-Related Cognitive Outcomes. Front Neuroanat 2018; 12:25. [PMID: 29681801 PMCID: PMC5898178 DOI: 10.3389/fnana.2018.00025] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 03/20/2018] [Indexed: 01/19/2023] Open
Abstract
Epilepsy is a paroxysmal neurological disorder characterized by recurrent and unprovoked seizures affecting approximately 50 million people worldwide. Cognitive dysfunction induced by seizures is a severe comorbidity of epilepsy and epilepsy syndromes and reduces patients’ quality of life. Seizures, along with accompanying histopathological and pathophysiological changes, are associated with cognitive comorbidities. Advances in imaging technology and computing allow anatomical and topological changes in neural networks to be visualized. Anatomical components including the hippocampus, amygdala, cortex, corpus callosum (CC), cerebellum and white matter (WM) are the fundamental components of seizure- and cognition-related topological networks. Damage to these structures and their substructures results in worsening of epilepsy symptoms and cognitive dysfunction. In this review article, we survey structural, network changes and topological alteration in different regions of the brain and in different epilepsy and epileptic syndromes, and discuss what these changes may mean for cognitive outcomes related to these disease states.
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Affiliation(s)
- Qian Wu
- Department of Neurology, First Affiliated Hospital, Kunming Medical University, Kunming, China
| | - Charlie W Zhao
- Department of Neuroscience, Yale School of Medicine, Yale University, New Haven, CT, United States
| | - Zhe Long
- Sydney Medical School and the Brain & Mind Institute, The University of Sydney, Camperdown, NSW, Australia
| | - Bo Xiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Li Feng
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
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16
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Chiang S, Guindani M, Yeh HJ, Dewar S, Haneef Z, Stern JM, Vannucci M. A Hierarchical Bayesian Model for the Identification of PET Markers Associated to the Prediction of Surgical Outcome after Anterior Temporal Lobe Resection. Front Neurosci 2017; 11:669. [PMID: 29259537 PMCID: PMC5723403 DOI: 10.3389/fnins.2017.00669] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 11/17/2017] [Indexed: 01/19/2023] Open
Abstract
We develop an integrative Bayesian predictive modeling framework that identifies individual pathological brain states based on the selection of fluoro-deoxyglucose positron emission tomography (PET) imaging biomarkers and evaluates the association of those states with a clinical outcome. We consider data from a study on temporal lobe epilepsy (TLE) patients who subsequently underwent anterior temporal lobe resection. Our modeling framework looks at the observed profiles of regional glucose metabolism in PET as the phenotypic manifestation of a latent individual pathologic state, which is assumed to vary across the population. The modeling strategy we adopt allows the identification of patient subgroups characterized by latent pathologies differentially associated to the clinical outcome of interest. It also identifies imaging biomarkers characterizing the pathological states of the subjects. In the data application, we identify a subgroup of TLE patients at high risk for post-surgical seizure recurrence after anterior temporal lobe resection, together with a set of discriminatory brain regions that can be used to distinguish the latent subgroups. We show that the proposed method achieves high cross-validated accuracy in predicting post-surgical seizure recurrence.
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Affiliation(s)
- Sharon Chiang
- Department of Statistics, Rice University, Houston, TX, United States.,School of Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Michele Guindani
- Department of Statistics, University of California, Irvine, Irvine, CA, United States
| | - Hsiang J Yeh
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Sandra Dewar
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Zulfi Haneef
- Department of Neurology, Baylor College of Medicine, Houston, TX, United States
| | - John M Stern
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Marina Vannucci
- Department of Statistics, Rice University, Houston, TX, United States
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17
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Neurochemical Changes and c-Fos Mapping in the Brain after Carisbamate Treatment of Rats Subjected to Lithium-Pilocarpine-Induced Status Epilepticus. Pharmaceuticals (Basel) 2017; 10:ph10040085. [PMID: 29104261 PMCID: PMC5748642 DOI: 10.3390/ph10040085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/20/2017] [Accepted: 10/27/2017] [Indexed: 12/03/2022] Open
Abstract
The administration of lithium–pilocarpine (LiPilo) in adult rats is a validated model reproducing the main clinical and neuropathological features of temporal lobe epilepsy (TLE). Previous studies have shown that carisbamate (CRS) has the property of modifying epileptogenesis in this model. When treated with CRS, about 50% of rats undergoing LiPilo status epilepticus (SE) develop non-convulsive seizures (NCS) instead of convulsive ones (commonly observed in TLE). The goal of this work was to determine some of the early changes that occur after CRS administration, as they could be involved in the insult- and epileptogenesis-modifying effects of CRS. Thus, we performed high-performance liquid chromatography (HPLC) to quantify levels of amino acids and monoamines, and c-Fos immunohistochemical labeling to map cerebral activation during seizures. Comparing rats treated one hour after SE onset with saline (CT), CRS, or diazepam (DZP), HPLC showed that 4 h after SE onset, dopamine (DA), norepinephrine (NE), and GABA levels were normal, whereas serotonin levels were increased. Using c-Fos labeling, we demonstrated increased activity in thalamic mediodorsal (MD) and laterodorsal (LD) nuclei in rats treated with CRS. In summary, at early times, CRS seems to modulate excitability by acting on some monoamine levels and increasing activity of MD and LD thalamic nuclei, suggesting a possible involvement of these nuclei in insult- and/or epileptogenesis-modifying effects of CRS.
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18
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Chiosa V, Groppa SA, Ciolac D, Koirala N, Mişina L, Winter Y, Moldovanu M, Muthuraman M, Groppa S. Breakdown of Thalamo-Cortical Connectivity Precedes Spike Generation in Focal Epilepsies. Brain Connect 2017; 7:309-320. [DOI: 10.1089/brain.2017.0487] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Vitalie Chiosa
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Department of Neurology and Neurosurgery, National Center of Epileptology, Institute of Emergency Medicine, Chisinau, Moldova
- Laboratory of Neurobiology and Medical Genetics, State University of Medicine and Pharmacy “Nicolae Testemiţanu,” Chisinau, Moldova
| | - Stanislav A. Groppa
- Department of Neurology and Neurosurgery, National Center of Epileptology, Institute of Emergency Medicine, Chisinau, Moldova
- Laboratory of Neurobiology and Medical Genetics, State University of Medicine and Pharmacy “Nicolae Testemiţanu,” Chisinau, Moldova
| | - Dumitru Ciolac
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Department of Neurology and Neurosurgery, National Center of Epileptology, Institute of Emergency Medicine, Chisinau, Moldova
- Laboratory of Neurobiology and Medical Genetics, State University of Medicine and Pharmacy “Nicolae Testemiţanu,” Chisinau, Moldova
| | - Nabin Koirala
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Liudmila Mişina
- Department of Neurology and Neurosurgery, National Center of Epileptology, Institute of Emergency Medicine, Chisinau, Moldova
- Laboratory of Neurobiology and Medical Genetics, State University of Medicine and Pharmacy “Nicolae Testemiţanu,” Chisinau, Moldova
| | - Yaroslav Winter
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Muthuraman Muthuraman
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sergiu Groppa
- Department of Neurology, Neuroimaging and Neurostimulation, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience Network (rmn2), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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19
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Li DH, Yang XF. Remote modulation of network excitability during deep brain stimulation for epilepsy. Seizure 2017; 47:42-50. [DOI: 10.1016/j.seizure.2017.02.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 01/20/2017] [Accepted: 02/28/2017] [Indexed: 12/18/2022] Open
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20
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Zemlyanaya AA, Kalinin VV, Zheleznova EV, Sokolova LV. [The changes in cognitive impairment in patients with epilepsy during the disease course (on example of executive functions)]. Zh Nevrol Psikhiatr Im S S Korsakova 2016; 116:25-31. [PMID: 28005043 DOI: 10.17116/jnevro20161169225-31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM To identify the relationship between executive functions (EF), personality traits and clinical characteristics of disease course. MATERIAL AND METHODS One hundred and five patients with partial epilepsy, including temporal lobe epilepsy (61%), lobe epilepsy (33%) and other forms (6%), were examined. Mean age of the patients was 30.24±8,67 years. EF were studied using the the Wisconsin Card Sorting Test (WCST) in 25 out of 105 patients of the main group. The patients were followed-up after 5.5 years. RESULTS Correlations between the EF decline and the age, illness duration and disability was found. Seizure remission and its duration have a positive effect on EF indices. There were no correlations with the age at seizure onset, severity of seizures, amount of medications used, psychopathological symptoms and left-handedness. The WCST scores were worse in patients with temporal lobe epilepsy and patients with alexithymia. A follow-up examination showed the relationship between the further EF decline and the left-sided localization of the epileptic focus as well as the absence of seizure remission. No relationship between the EF deficit and antiepileptic treatment was found. CONCLUSION The EF deficit was observed in all forms of epilepsy, it was correlated with disability of patients, may be aggravated by personality and neurobiological characteristics and increased with the persistence of seizures. Based on the results of the study, the achievement of remission is needed in treatment tactics for epilepsy to preserve cognitive functioning and social well-being of patients.
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Affiliation(s)
- A A Zemlyanaya
- Moscow Research Institute of Psychiatry - the branch of Federal Medical Research Centre of Psychiatry and Narcology under the RF Ministry of Public Health, Moscow, Russia
| | - V V Kalinin
- Moscow Research Institute of Psychiatry - the branch of Federal Medical Research Centre of Psychiatry and Narcology under the RF Ministry of Public Health, Moscow, Russia
| | - E V Zheleznova
- Moscow Research Institute of Psychiatry - the branch of Federal Medical Research Centre of Psychiatry and Narcology under the RF Ministry of Public Health, Moscow, Russia
| | - L V Sokolova
- Moscow Research Institute of Psychiatry - the branch of Federal Medical Research Centre of Psychiatry and Narcology under the RF Ministry of Public Health, Moscow, Russia
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21
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Zhang Z, Liao W, Xu Q, Wei W, Zhou HJ, Sun K, Yang F, Mantini D, Ji X, Lu G. Hippocampus-associated causal network of structural covariance measuring structural damage progression in temporal lobe epilepsy. Hum Brain Mapp 2016; 38:753-766. [PMID: 27677885 DOI: 10.1002/hbm.23415] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 08/24/2016] [Accepted: 09/21/2016] [Indexed: 01/06/2023] Open
Abstract
In mesial temporal lobe epilepsy (mTLE), the causal relationship of morphometric alterations between hippocampus and the other regions, that is, how the hippocampal atrophy leads to progressive morphometric alterations in the epileptic network regions remains largely unclear. In this study, a causal network of structural covariance (CaSCN) was proposed to map the causal effects of hippocampal atrophy on the network-based morphometric alterations in mTLE. It was hypothesized that if cross-sectional morphometric MRI data could be attributed temporal information, for example, by sequencing the data according to disease progression information, GCA would be a feasible approach for constructing a CaSCN. Based on a large cohort of mTLE patients (n = 108), the hippocampus-associated CaSCN revealed that the hippocampus and the thalamus were prominent nodes exerting causal effects (i.e., GM reduction) on other regions and that the prefrontal cortex and cerebellum were prominent nodes being subject to causal effects. Intriguingly, compensatory increased gray matter volume in the contralateral temporal region and post cingulate cortex were also detected. The method unraveled richer information for mapping network atrophy in mTLE relative to the traditional methods of stage-specific comparisons and structured covariance network. This study provided new evidence on the network spread mechanism in terms of the causal influence of hippocampal atrophy on progressive brain structural alterations in mTLE. Hum Brain Mapp 38:753-766, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Zhiqiang Zhang
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China.,State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, 210093, China
| | - Wei Liao
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China.,Center for Cognition and Brain Disorders, Affiliated Hospital of Hangzhou Normal University, Hangzhou, 310015, China
| | - Qiang Xu
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China
| | - Wei Wei
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China
| | - Helen Juan Zhou
- Center for Cognitive Neuroscience, Neuroscience and Behavioral Disorder Program, Duke-NUS Graduate Medical School, National University of Singapore, Singapore, Singapore
| | - Kangjian Sun
- Department of Neurosurgery, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China
| | - Fang Yang
- Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China
| | - Dante Mantini
- Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Belgium
| | - Xueman Ji
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China
| | - Guangming Lu
- Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, China.,State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, 210093, China
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22
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Kim JS, Koo DL, Joo EY, Kim ST, Seo DW, Hong SB. Asymmetric Gray Matter Volume Changes Associated with Epilepsy Duration and Seizure Frequency in Temporal-Lobe-Epilepsy Patients with Favorable Surgical Outcome. J Clin Neurol 2016; 12:323-31. [PMID: 27449913 PMCID: PMC4960217 DOI: 10.3988/jcn.2016.12.3.323] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 12/25/2015] [Accepted: 12/28/2015] [Indexed: 11/17/2022] Open
Abstract
Background and Purpose This study aimed to estimate the changes in gray matter volume (GMV) and their hemispheric difference in patients with mesial temporal lobe epilepsy (MTLE) using a voxel-based morphometry (VBM) methodology, and to determine whether GMV changes are correlated with clinical features. Methods VBM analysis of brain MRI using statistical parametric mapping 8 (SPM8) was performed for 30 left MTLE (LMTLE) and 30 right MTLE (RMTLE) patients and 30 age- and sex-matched healthy controls. We also analyzed the correlations between GMV changes and clinical features of MTLE patients. Results In SPM8-based analyses, MTLE patients showed significant GMV reductions in the hippocampus ipsilateral to the epileptic focus, bilateral thalamus, and contralateral putamen in LMTLE patients. The GMV reductions were more extensive in the ipsilateral hippocampus, thalamus, caudate, putamen, uncus, insula, inferior temporal gyrus, middle occipital gyrus, cerebellum, and paracentral lobule in RMTLE patients. These patients also exhibited notable reductions of GMV in the contralateral hippocampus, thalamus, caudate, putamen, and inferior frontal gyrus. We observed that GMV reduction was positively correlated with several clinical features (epilepsy duration and seizure frequency in RMTLE, and history of febrile seizure in LMTLE) and negatively correlated with seizure onset age in both the RMTLE and LMTLE groups. Conclusions Our study revealed GMV decreases in the hippocampus and extrahippocampal regions. Furthermore, the GMV reduction was more extensive in the RMTLE group than in the LMTLE group, since it included the contralateral hemisphere in the former. This difference in the GMV reduction patterns between LMTLE and RMTLE may be related to a longer epilepsy duration and higher seizure frequency in the latter.
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Affiliation(s)
- Jeong Sik Kim
- Department of Neurology, Neuroscience Center, Samsung Medical Center and Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Biomedical Research Institute (SBRI), Seoul, Korea
| | - Dae Lim Koo
- Department of Neurology, Seoul National University Boramae Hospital, Seoul, Korea
| | - Eun Yeon Joo
- Department of Neurology, Neuroscience Center, Samsung Medical Center and Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Biomedical Research Institute (SBRI), Seoul, Korea
| | - Sung Tae Kim
- Department of Radiology, Samsung Medical Center, Sungkyunwan University School of Medicine, Seoul, Korea
| | - Dae Won Seo
- Department of Neurology, Neuroscience Center, Samsung Medical Center and Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Biomedical Research Institute (SBRI), Seoul, Korea
| | - Seung Bong Hong
- Department of Neurology, Neuroscience Center, Samsung Medical Center and Samsung Advanced Institute for Health Sciences & Technology (SAIHST), Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Biomedical Research Institute (SBRI), Seoul, Korea.
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23
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Krishna V, King NKK, Sammartino F, Strauss I, Andrade DM, Wennberg RA, Lozano AM. Anterior Nucleus Deep Brain Stimulation for Refractory Epilepsy. Neurosurgery 2016; 78:802-11. [DOI: 10.1227/neu.0000000000001197] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Abstract
BACKGROUND:
Anterior nucleus (AN) deep brain stimulation (DBS) is a palliative treatment for medically refractory epilepsy. The long-term efficacy and the optimal target localization for AN DBS are not well understood.
OBJECTIVE:
To analyze the long-term efficacy of AN DBS and its predictors.
METHODS:
We performed a retrospective review of 16 patients who underwent AN DBS. We selected only patients with reliable seizure frequency data and at least a 1-year follow-up. We studied the duration of the seizure reduction after DBS insertion and before stimulation (the insertional effect) and its association with long-term outcome. We modeled the volume of activation using the active contacts, stimulation parameters, and postoperative imaging. The overlap of this volume was plotted in Montreal Neurological Institute 152 space in 7 patients with significant clinical efficacy.
RESULTS:
Nine patients reported a decrease in seizure frequency immediately after electrode insertion (insertional or microthalamotomy effect). The duration of insertional effect varied from 2 to 4 months. However, 1 patient had a long-term insertional effect of 36 months. Altogether, 11 patients reported >50% decrease in seizure frequency with long-term stimulation. The most common pattern of seizure control was immediate and sustained stimulation benefit (n = 8). In patients with long-term stimulation benefit, the efficacious target was localized in the anteroventral AN in close proximity to the mammillothalamic tract.
CONCLUSION:
AN DBS is efficacious in the control of seizure frequency in selected patients. An insertional effect is commonly observed (56%). The most efficacious site of stimulation appears to be the anteroventral AN.
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Affiliation(s)
| | | | | | - Ido Strauss
- Department of Neurosurgery, Tel Aviv Medical Center, Tel Aviv University, Tel Aviv, Israel
| | - Danielle M. Andrade
- Department of Neurology, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Richard A. Wennberg
- Department of Neurology, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
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24
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Park KM, Han YH, Kim TH, Mun CW, Shin KJ, Ha SY, Park J, Hur YJ, Kim HY, Park SH, Kim SE. Cerebellar white matter changes in patients with newly diagnosed partial epilepsy of unknown etiology. Clin Neurol Neurosurg 2015; 138:25-30. [DOI: 10.1016/j.clineuro.2015.07.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 07/10/2015] [Accepted: 07/24/2015] [Indexed: 10/23/2022]
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25
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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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26
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Bernhardt BC, Bonilha L, Gross DW. Network analysis for a network disorder: The emerging role of graph theory in the study of epilepsy. Epilepsy Behav 2015; 50:162-70. [PMID: 26159729 DOI: 10.1016/j.yebeh.2015.06.005] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 01/01/2023]
Abstract
Recent years have witnessed a paradigm shift in the study and conceptualization of epilepsy, which is increasingly understood as a network-level disorder. An emblematic case is temporal lobe epilepsy (TLE), the most common drug-resistant epilepsy that is electroclinically defined as a focal epilepsy and pathologically associated with hippocampal sclerosis. In this review, we will summarize histopathological, electrophysiological, and neuroimaging evidence supporting the concept that the substrate of TLE is not limited to the hippocampus alone, but rather is broadly distributed across multiple brain regions and interconnecting white matter pathways. We will introduce basic concepts of graph theory, a formalism to quantify topological properties of complex systems that has recently been widely applied to study networks derived from brain imaging and electrophysiology. We will discuss converging graph theoretical evidence indicating that networks in TLE show marked shifts in their overall topology, providing insight into the neurobiology of TLE as a network-level disorder. Our review will conclude by discussing methodological challenges and future clinical applications of this powerful analytical approach.
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Affiliation(s)
- Boris C Bernhardt
- Neuroimaging of Epilepsy Laboratory, Brain Imaging Center, Montreal Neurological Institute and Hospital, McGill University, Montreal, QC, Canada; Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
| | - Leonardo Bonilha
- Department of Neurology, Medical University of South Carolina, SC, USA
| | - Donald W Gross
- Division of Neurology, Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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27
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Bonilha L, Keller SS. Quantitative MRI in refractory temporal lobe epilepsy: relationship with surgical outcomes. Quant Imaging Med Surg 2015; 5:204-24. [PMID: 25853080 DOI: 10.3978/j.issn.2223-4292.2015.01.01] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 01/07/2015] [Indexed: 11/14/2022]
Abstract
Medically intractable temporal lobe epilepsy (TLE) remains a serious health problem. Across treatment centers, up to 40% of patients with TLE will continue to experience persistent postoperative seizures at 2-year follow-up. It is unknown why such a large number of patients continue to experience seizures despite being suitable candidates for resective surgery. Preoperative quantitative MRI techniques may provide useful information on why some patients continue to experience disabling seizures, and may have the potential to develop prognostic markers of surgical outcome. In this article, we provide an overview of how quantitative MRI morphometric and diffusion tensor imaging (DTI) data have improved the understanding of brain structural alterations in patients with refractory TLE. We subsequently review the studies that have applied quantitative structural imaging techniques to identify the neuroanatomical factors that are most strongly related to a poor postoperative prognosis. In summary, quantitative imaging studies strongly suggest that TLE is a disorder affecting a network of neurobiological systems, characterized by multiple and inter-related limbic and extra-limbic network abnormalities. The relationship between brain alterations and postoperative outcome are less consistent, but there is emerging evidence suggesting that seizures are less likely to remit with surgery when presurgical abnormalities are observed in the connectivity supporting brain regions serving as network nodes located outside the resected temporal lobe. Future work, possibly harnessing the potential from multimodal imaging approaches, may further elucidate the etiology of persistent postoperative seizures in patients with refractory TLE. Furthermore, quantitative imaging techniques may be explored to provide individualized measures of postoperative seizure freedom outcome.
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Affiliation(s)
- Leonardo Bonilha
- 1 Department of Neurology and Neurosurgery, Medical University of South Carolina, Charleston, SC 29425, USA ; 2 Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK ; 3 Department of Radiology, The Walton Centre NHS Foundation Trust, Liverpool, UK ; 4 Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Simon S Keller
- 1 Department of Neurology and Neurosurgery, Medical University of South Carolina, Charleston, SC 29425, USA ; 2 Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK ; 3 Department of Radiology, The Walton Centre NHS Foundation Trust, Liverpool, UK ; 4 Department of Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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28
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Tu S, Miller L, Piguet O, Hornberger M. Accelerated forgetting of contextual details due to focal medio-dorsal thalamic lesion. Front Behav Neurosci 2014; 8:320. [PMID: 25309371 PMCID: PMC4163931 DOI: 10.3389/fnbeh.2014.00320] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/28/2014] [Indexed: 11/13/2022] Open
Abstract
Effects of thalamic nuclei damage and related white matter tracts on memory performance are still debated. This is particularly evident for the medio-dorsal thalamus which has been less clear in predicting amnesia than anterior thalamus changes. The current study addresses this issue by assessing 7 thalamic stroke patients with consistent unilateral lesions focal to the left medio-dorsal nuclei for immediate and delayed memory performance on standard visual and verbal tests of anterograde memory, and over the long-term (>24 h) on an object-location associative memory task. Thalamic patients showed selective impairment to delayed recall, but intact recognition memory. Patients also showed accelerated forgetting of contextual details after a 24 h delay, compared to controls. Importantly, the mammillothalamic tract was intact in all patients, which suggests a role for the medio-dorsal nuclei in recall and early consolidation memory processes.
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Affiliation(s)
- Sicong Tu
- Neuroscience Research Australia, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia ; Australian Research Council Centre of Excellence in Cognition and its Disorders Sydney, NSW, Australia
| | - Laurie Miller
- Australian Research Council Centre of Excellence in Cognition and its Disorders Sydney, NSW, Australia ; Central Clinical School, Neuropsychology Unit, Royal Prince Alfred Hospital, University of Sydney Sydney, NSW, Australia
| | - Olivier Piguet
- Neuroscience Research Australia, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia ; Australian Research Council Centre of Excellence in Cognition and its Disorders Sydney, NSW, Australia
| | - Michael Hornberger
- Neuroscience Research Australia, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia ; Australian Research Council Centre of Excellence in Cognition and its Disorders Sydney, NSW, Australia ; Department of Clinical Neurosciences, University of Cambridge Cambridge, UK
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29
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Laxpati NG, Kasoff WS, Gross RE. Deep brain stimulation for the treatment of epilepsy: circuits, targets, and trials. Neurotherapeutics 2014; 11:508-26. [PMID: 24957200 PMCID: PMC4121455 DOI: 10.1007/s13311-014-0279-9] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Deep brain stimulation (DBS) has proven remarkably safe and effective in the treatment of movement disorders. As a result, it is being increasingly applied to a range of neurologic and psychiatric disorders, including medically refractory epilepsy. This review will examine the use of DBS in epilepsy, including known targets, mechanisms of neuromodulation and seizure control, published clinical evidence, and novel technologies. Cortical and deep neuromodulation for epilepsy has a long experimental history, but only recently have better understanding of epileptogenic networks, precise stereotactic techniques, and rigorous trial design combined to improve the quality of available evidence and make DBS a viable treatment option. Nonetheless, underlying mechanisms, anatomical targets, and stimulation parameters remain areas of active investigation.
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Affiliation(s)
- Nealen G. Laxpati
- />Department of Neurosurgery, Emory University School of Medicine, 1365 Clifton Road NE, Atlanta, GA 30322 USA
- />Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA USA
| | - Willard S. Kasoff
- />Division of Neurosurgery, Department of Surgery, University of Arizona, Tucson, AZ USA
| | - Robert E. Gross
- />Department of Neurosurgery, Emory University School of Medicine, 1365 Clifton Road NE, Atlanta, GA 30322 USA
- />Department of Neurology, Emory University School of Medicine, Atlanta, GA USA
- />Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA USA
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30
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Labate A, Mumoli L, Gambardella A. Thalamotemporal impairment in benign temporal lobe epilepsy: same hypotheses? Epilepsia 2014; 55:944. [PMID: 24924646 DOI: 10.1111/epi.12636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Angelo Labate
- Institute of Neurology, University "Magna Graecia", Catanzaro, Italy; Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Viale Europa, Germaneto (CZ), Italy.
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31
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Graph theory findings in the pathophysiology of temporal lobe epilepsy. Clin Neurophysiol 2014; 125:1295-305. [PMID: 24831083 DOI: 10.1016/j.clinph.2014.04.004] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 04/08/2014] [Accepted: 04/10/2014] [Indexed: 01/26/2023]
Abstract
Temporal lobe epilepsy (TLE) is the most common form of adult epilepsy. Accumulating evidence has shown that TLE is a disorder of abnormal epileptogenic networks, rather than focal sources. Graph theory allows for a network-based representation of TLE brain networks, and has potential to illuminate characteristics of brain topology conducive to TLE pathophysiology, including seizure initiation and spread. We review basic concepts which we believe will prove helpful in interpreting results rapidly emerging from graph theory research in TLE. In addition, we summarize the current state of graph theory findings in TLE as they pertain its pathophysiology. Several common findings have emerged from the many modalities which have been used to study TLE using graph theory, including structural MRI, diffusion tensor imaging, surface EEG, intracranial EEG, magnetoencephalography, functional MRI, cell cultures, simulated models, and mouse models, involving increased regularity of the interictal network configuration, altered local segregation and global integration of the TLE network, and network reorganization of temporal lobe and limbic structures. As different modalities provide different views of the same phenomenon, future studies integrating data from multiple modalities are needed to clarify findings and contribute to the formation of a coherent theory on the pathophysiology of TLE.
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32
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Keller SS, O'Muircheartaigh J, Traynor C, Towgood K, Barker GJ, Richardson MP. Thalamotemporal impairment in temporal lobe epilepsy: a combined MRI analysis of structure, integrity, and connectivity. Epilepsia 2014; 55:306-15. [PMID: 24447099 PMCID: PMC4074767 DOI: 10.1111/epi.12520] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2013] [Indexed: 12/12/2022]
Abstract
Objective Thalamic abnormality in temporal lobe epilepsy (TLE) is well known from imaging studies, but evidence is lacking regarding connectivity profiles of the thalamus and their involvement in the disease process. We used a novel multisequence magnetic resonance imaging (MRI) protocol to elucidate the relationship between mesial temporal and thalamic pathology in TLE. Methods For 23 patients with TLE and 23 healthy controls, we performed T1-weighted (for analysis of tissue structure), diffusion tensor imaging (tissue connectivity), and T1 and T2 relaxation (tissue integrity) MRI across the whole brain. We used connectivity-based segmentation to determine connectivity patterns of thalamus to ipsilateral cortical regions (occipital, parietal, prefrontal, postcentral, precentral, and temporal). We subsequently determined volumes, mean tractography streamlines, and mean T1 and T2 relaxometry values for each thalamic segment preferentially connecting to a given cortical region, and of the hippocampus and entorhinal cortex. Results As expected, patients had significant volume reduction and increased T2 relaxation time in ipsilateral hippocampus and entorhinal cortex. There was bilateral volume loss, mean streamline reduction, and T2 increase of the thalamic segment preferentially connected to temporal lobe, corresponding to anterior, dorsomedial, and pulvinar thalamic regions, with no evidence of significant change in any other thalamic segments. Left and right thalamotemporal segment volume and T2 were significantly correlated with volume and T2 of ipsilateral (epileptogenic), but not contralateral (nonepileptogenic), mesial temporal structures. Significance These convergent and robust data indicate that thalamic abnormality in TLE is restricted to the area of the thalamus that is preferentially connected to the epileptogenic temporal lobe. The degree of thalamic pathology is related to the extent of mesial temporal lobe damage in TLE.
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Affiliation(s)
- Simon S Keller
- The Department of Clinical Neuroscience, Institute of Psychiatry, King's College London, London, United Kingdom; The Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
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33
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Sinjab B, Martinian L, Sisodiya SM, Thom M. Regional thalamic neuropathology in patients with hippocampal sclerosis and epilepsy: a postmortem study. Epilepsia 2013; 54:2125-33. [PMID: 24138281 PMCID: PMC3995016 DOI: 10.1111/epi.12403] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2013] [Indexed: 12/01/2022]
Abstract
Purpose Clinical, experimental, and neuroimaging data all indicate that the thalamus is involved in the network of changes associated with temporal lobe epilepsy (TLE), particularly in association with hippocampal sclerosis (HS), with potential roles in seizure initiation and propagation. Pathologic changes in the thalamus may be a result of an initial insult, ongoing seizures, or retrograde degeneration through reciprocal connections between thalamic and limbic regions. Our aim was to carry out a neuropathologic analysis of the thalamus in a postmortem (PM) epilepsy series, to assess the distribution, severity, and nature of pathologic changes and its association with HS. Methods Twenty-four epilepsy PM cases (age range 25–87 years) and eight controls (age range 38–85 years) were studied. HS was classified as unilateral (UHS, 11 cases), bilateral (BHS, 4 cases) or absent (No-HS, 9 cases). Samples from the left and right sides of the thalamus were stained with cresyl violet (CV), and for glial firbillary acidic protein (GFAP) and synaptophysin. Using image analysis, neuronal densities (NDs) or field fraction staining values (GFAP, synaptophysin) were measured in four thalamic nuclei: anteroventral nucleus (AV), lateral dorsal nucleus (LD), mediodorsal nucleus (MD), and ventrolateral nucleus (VL). The results were compared within and between cases. Key Findings The severity, nature, and distribution of thalamic pathology varied between cases. A pattern that emerged was a preferential involvement of the MD in UHS cases with a reduction in mean ND ipsilateral to the side of HS (p = 0.05). In UHS cases, greater field fraction values for GFAP and lower values for synaptophysin and ND were seen in the majority of cases in the MD ipsilateral to the side of sclerosis compared to other thalamic nuclei. In addition, differences in the mean ND between classical HS, atypical HS, and No-HS cases were noted in the ipsilateral MD (p < 0.05), with lower values observed in HS. Significance Our study demonstrates that stereotypical pathologic changes, as seen in HS, are not clearly defined in the thalamus. This may be partly explained by the heterogeneity of our PM study group. With quantitation, there is some evidence for preferential involvement of the MD, suggesting a potential role in TLE, which requires further investigation.
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Affiliation(s)
- Barah Sinjab
- Department of Clinical and Experimental Epilepsy, Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, United Kingdom
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34
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Bernhardt BC, Hong S, Bernasconi A, Bernasconi N. Imaging structural and functional brain networks in temporal lobe epilepsy. Front Hum Neurosci 2013; 7:624. [PMID: 24098281 PMCID: PMC3787804 DOI: 10.3389/fnhum.2013.00624] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 09/09/2013] [Indexed: 11/24/2022] Open
Abstract
Early imaging studies in temporal lobe epilepsy (TLE) focused on the search for mesial temporal sclerosis, as its surgical removal results in clinically meaningful improvement in about 70% of patients. Nevertheless, a considerable subgroup of patients continues to suffer from post-operative seizures. Although the reasons for surgical failure are not fully understood, electrophysiological and imaging data suggest that anomalies extending beyond the temporal lobe may have negative impact on outcome. This hypothesis has revived the concept of human epilepsy as a disorder of distributed brain networks. Recent methodological advances in non-invasive neuroimaging have led to quantify structural and functional networks in vivo. While structural networks can be inferred from diffusion MRI tractography and inter-regional covariance patterns of structural measures such as cortical thickness, functional connectivity is generally computed based on statistical dependencies of neurophysiological time-series, measured through functional MRI or electroencephalographic techniques. This review considers the application of advanced analytical methods in structural and functional connectivity analyses in TLE. We will specifically highlight findings from graph-theoretical analysis that allow assessing the topological organization of brain networks. These studies have provided compelling evidence that TLE is a system disorder with profound alterations in local and distributed networks. In addition, there is emerging evidence for the utility of network properties as clinical diagnostic markers. Nowadays, a network perspective is considered to be essential to the understanding of the development, progression, and management of epilepsy.
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Affiliation(s)
- Boris C Bernhardt
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University Montreal, QC, Canada ; Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany
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Doucet GE, Skidmore C, Sharan AD, Sperling MR, Tracy JI. Functional connectivity abnormalities vary by amygdala subdivision and are associated with psychiatric symptoms in unilateral temporal epilepsy. Brain Cogn 2013; 83:171-82. [PMID: 24036129 DOI: 10.1016/j.bandc.2013.08.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/11/2013] [Accepted: 08/21/2013] [Indexed: 10/26/2022]
Abstract
The amygdala has been described as a structure affected by mesial temporal lobe epilepsy (MTLE). Indeed, it is suggested that amygdala abnormalities are related to the co-morbid depression and anxiety reported in MTLE. In this context, we investigated the relation between functional connectivity (FC) emerging from this structure in fMRI and depression and anxiety levels reported in MTLE patients. We focused on resting-state BOLD activity and evaluated whether FC differences emerge from each of three amygdala subdivisions (laterobasal, centromedial and superficial) in left and right MTLE groups, compared with healthy controls. Results revealed significant differences between patient groups and controls. Specifically, the left MTLE group showed abnormal FC for the left-sided seeds only. Furthermore, regardless of the seed, we observed more reliable differences between the right MTLE group and controls. Further analysis of these results revealed correlations between these impaired connectivities and psychiatric symptoms in both MTLE groups. Opposite relations, however, were highlighted: the more depressed or anxious the right MTLE patients, the closer their FC values approached controls; whereas the less anxious the left MTLE patients, the closer their FC values were normative. These results highlight how MTLE alter FC emerging from the limbic system. Overall, our data demonstrate that right TLE has a more maladaptive impact on emotion-related networks, in ways specific to the amygdala region, and the emotion symptom involved, than left TLE.
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Affiliation(s)
- Gaëlle E Doucet
- Department of Neurology, Thomas Jefferson University, United States; Department of Neurosurgery, Thomas Jefferson University, United States
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Willment KC, Golby A. Hemispheric lateralization interrupted: material-specific memory deficits in temporal lobe epilepsy. Front Hum Neurosci 2013; 7:546. [PMID: 24032014 PMCID: PMC3759288 DOI: 10.3389/fnhum.2013.00546] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 08/19/2013] [Indexed: 02/01/2023] Open
Abstract
The hemispheric lateralization of memory has largely been informed through the study of patients with temporal lobe epilepsy originating from medial temporal sources (mTLE). The material-specific model of memory relies on the basic framework that the left temporal lobe mediates verbal memories, while the right temporal lobe mediates non-verbal memories. Over the years, this model has been refined, and even challenged, as our understanding of the material-specific memory deficits in mTLE has been further elaborated in the neuropsychological and neuroimaging literature. The first goal of this mini-review is to highlight the major findings in the mTLE literature that have advanced and expanded our understanding of material-specific memory deficits in mTLE. Second, we will review how functional neuroimaging patterns of material-specific hemispheric lateralization in mTLE are being translated into the innovative clinical application of preoperative fMRI memory mapping.
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Affiliation(s)
- Kim Celone Willment
- Department of Neurology, Brigham and Women's Hospital , Boston, MA , USA ; Department of Psychiatry, Brigham and Women's Hospital , Boston, MA , USA ; Golby Lab, A Surgical Brain Mapping Laboratory, Department of Neurosurgery, Brigham and Women's Hospital , Boston, MA , USA
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Mumoli L, Labate A, Vasta R, Cherubini A, Ferlazzo E, Aguglia U, Quattrone A, Gambardella A. Detection of hippocampal atrophy in patients with temporal lobe epilepsy: a 3-Tesla MRI shape. Epilepsy Behav 2013; 28:489-93. [PMID: 23892579 DOI: 10.1016/j.yebeh.2013.05.035] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 05/22/2013] [Accepted: 05/25/2013] [Indexed: 01/18/2023]
Abstract
In patients with mesial temporal lobe epilepsy (MTLE), brain MRI often detects hippocampal sclerosis (HS). Almost half of patients with MTLE do not show any hippocampal damage on visual or volumetric assessment. Here, we wished to prospectively assess 65 patients with MTLE (41 women, mean age: 39±10years, range: 21-69; right (12/65 patients) (MRI-negative) nMTLE; right (14/65 patients) (MRI-positive with HS) pMTLE; left (24/65 patients) nMTLE; and left (15/65 patients) pMTLE) using shape analysis (SA). There were significant differences among pMTLE versus nMTLE for age at seizure onset (20.2±12.8 vs. 31.8±16.7years; p=.0029), duration of epilepsy (14.6±12.7 vs. 21.3±9.6years; p=.0227), risk of refractoriness (p=.0067), frequency of antecedent febrile convulsions (FCs) (p<.001), as well as a history of epilepsy or FCs (p=.0104). All the subjects underwent the same 3-Tesla MRI protocol. Shape analysis of hippocampal formation was conducted comparing each group versus 44 matched controls. In all four subgroups, SA detected a significant atrophy in the corresponding hippocampus that coincided with the epileptogenic area. The damage was significantly more severe in patients with pMTLE (F value: 5.00) than in subgroups with nMTLE (F value: 3.50) and mainly corresponded to the CA1 subregion and subiculum. In the patients with MTLE, SA detects hippocampal damage that lateralizes with the epileptogenic area. Such damage is most prominent in the CA1 subregion and subiculum that are crucial in the pathogenesis of MTLE.
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Affiliation(s)
- Laura Mumoli
- Institute of Neurology, University Magna Græcia, Catanzaro, Italy
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Memarian N, Thompson PM, Engel J, Staba RJ. Quantitative analysis of structural neuroimaging of mesial temporal lobe epilepsy. ACTA ACUST UNITED AC 2013; 5. [PMID: 24319498 DOI: 10.2217/iim.13.28] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mesial temporal lobe epilepsy (MTLE) is the most common of the surgically remediable drug-resistant epilepsies. MRI is the primary diagnostic tool to detect anatomical abnormalities and, when combined with EEG, can more accurately identify an epileptogenic lesion, which is often hippocampal sclerosis in cases of MTLE. As structural imaging technology has advanced the surgical treatment of MTLE and other lesional epilepsies, so too have the analysis techniques that are used to measure different structural attributes of the brain. These techniques, which are reviewed here and have been used chiefly in basic research of epilepsy and in studies of MTLE, have identified different types and the extent of anatomical abnormalities that can extend beyond the affected hippocampus. These results suggest that structural imaging and sophisticated imaging analysis could provide important information to identify networks capable of generating spontaneous seizures and ultimately help guide surgical therapy that improves postsurgical seizure-freedom outcomes.
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Affiliation(s)
- Negar Memarian
- Department of Neurology, Reed, Neurological Research Center, Suite, 2155, University of California, 710 Westwood Plaza, Los Angeles, CA 90095, USA
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Pan JW, Spencer DD, Kuzniecky R, Duckrow RB, Hetherington H, Spencer SS. Metabolic networks in epilepsy by MR spectroscopic imaging. Acta Neurol Scand 2012; 126:411-20. [PMID: 22574807 DOI: 10.1111/j.1600-0404.2012.01665.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2012] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The concept of an epileptic network has long been suggested from both animal and human studies of epilepsy. Based on the common observation that the MR spectroscopic imaging measure of NAA/Cr is sensitive to neuronal function and injury, we use this parameter to assess for the presence of a metabolic network in mesial temporal lobe epilepsy (MTLE) patients. MATERIALS AND METHODS A multivariate factor analysis is performed with controls and MTLE patients, using NAA/Cr measures from 12 loci: the bilateral hippocampi, thalami, basal ganglia, and insula. The factor analysis determines which and to what extent these loci are metabolically covarying. RESULTS We extract two independent factors that explain the data's variability in control and MTLE patients. In controls, these factors characterize a 'thalamic' and 'dominant subcortical' function. The MTLE patients also exhibit a 'thalamic' factor, in addition to a second factor involving the ipsilateral insula and bilateral basal ganglia. CONCLUSIONS These data suggest that MTLE patients demonstrate a metabolic network that involves the thalami, also seen in controls. The MTLE patients also display a second set of metabolically covarying regions that may be a manifestation of the epileptic network that characterizes limbic seizure propagation.
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Affiliation(s)
| | - D. D. Spencer
- Department of Neurosurgery; Yale School of Medicine; New Haven; CT; USA
| | - R. Kuzniecky
- Department of Neurology; NYU School of Medicine; New York; NY; USA
| | - R. B. Duckrow
- Department of Neurology; Yale School of Medicine; New Haven; CT; USA
| | - H. Hetherington
- Department of Neurosurgery; Yale School of Medicine; New Haven; CT; USA
| | - S. S. Spencer
- Department of Neurology; Yale School of Medicine; New Haven; CT; 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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Gutierrez-Galve L, Flugel D, Thompson PJ, Koepp MJ, Symms MR, Ron MA, Foong J. Cortical abnormalities and their cognitive correlates in patients with temporal lobe epilepsy and interictal psychosis. Epilepsia 2012; 53:1077-87. [DOI: 10.1111/j.1528-1167.2012.03504.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Doucet G, Osipowicz K, Sharan A, Sperling MR, Tracy JI. Extratemporal functional connectivity impairments at rest are related to memory performance in mesial temporal epilepsy. Hum Brain Mapp 2012; 34:2202-16. [PMID: 22505284 DOI: 10.1002/hbm.22059] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 01/19/2011] [Accepted: 01/20/2012] [Indexed: 11/12/2022] Open
Abstract
Mesial temporal lobe epilepsy (MTLE) is the most frequent form of focal epilepsy. At rest, there is evidence that brain abnormalities in MTLE are not limited to the epileptogenic region, but extend throughout the whole brain. It is also well established that MTLE patients suffer from episodic memory deficits. Thus, we investigated the relation between the functional connectivity seen at rest in fMRI and episodic memory impairments in MTLE. We focused on resting state BOLD activity and evaluated whether functional connectivity (FC) differences emerge from MTL seeds in left and right MTLE groups, compared with healthy controls. Results revealed significant FC reductions in both patient groups, localized in angular gyri, thalami, posterior cingulum and medial frontal cortex. We found that the FC between the left non-pathologic MTL and the medial frontal cortex was positively correlated with the delayed recall score of a non-verbal memory test in right MTLE patients, suggesting potential adaptive changes to preserve this memory function. In contrast, we observed a negative correlation between a verbal memory test and the FC between the left pathologic MTL and posterior cingulum in left MTLE patients, suggesting potential functional maladaptative changes in the pathologic hemisphere. Overall, the present study provides some indication that left MTLE may be more impairing than right MTLE patients to normative functional connectivity. Our data also indicates that the pattern of extra-temporal FC may vary as a function of episodic memory material and each hemisphere's capacity for cognitive reorganization.
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Affiliation(s)
- Gaëlle Doucet
- Department of Neurology, Cognitive Neuroscience and Brain Imaging Laboratory, Thomas Jefferson University, Jefferson Medical College, 901 Walnut St., Philadelphia, PA 19107, USA
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Alhusaini S, Doherty CP, Scanlon C, Ronan L, Maguire S, Borgulya G, Brennan P, Delanty N, Fitzsimons M, Cavalleri GL. A cross-sectional MRI study of brain regional atrophy and clinical characteristics of temporal lobe epilepsy with hippocampal sclerosis. Epilepsy Res 2011; 99:156-66. [PMID: 22197033 DOI: 10.1016/j.eplepsyres.2011.11.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 11/09/2011] [Accepted: 11/13/2011] [Indexed: 11/29/2022]
Abstract
PURPOSE Applying a cross-sectional design, we set out to further characterize the significance of extrahippocampal brain atrophy in a large sample of 'sporadic' mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE+HS). By evaluating the influence of epilepsy chronicity on structural atrophy, this work represents an important step towards the characterization of MRI-based volumetric measurements as genetic endophenotypes for this condition. METHODS Using an automated brain segmentation technique, MRI-based volume measurements of several brain regions were compared between 75 patients with 'sporadic' MTLE+HS and 50 healthy controls. Applying linear regression models, we examined the relationship between structural atrophy and important clinical features of MTLE+HS, including disease duration, lifetime number of partial and generalized seizures, and history of initial precipitating insults (IPIs). RESULTS Significant volume loss was detected in ipsilateral hippocampus, amygdala, thalamus, and cerebral white matter (WM). In addition, contralateral hippocampal and bilateral cerebellar grey matter (GM) volume loss was observed in left MTLE+HS patients. Hippocampal, amygdalar, and cerebral WM volume loss correlated with duration of epilepsy. This correlation was stronger in patients with prior IPIs history. Further, cerebral WM, cerebellar GM, and contralateral hippocampal volume loss correlated with lifetime number of generalized seizures. CONCLUSION Our findings confirm that multiple brain regions beyond the hippocampus are involved in the pathogenesis of MTLE+HS. IPIs are an important factor influencing the rate of regional atrophy but our results also support a role for processes related to epilepsy chronicity. The consequence of epilepsy chronicity on candidate brain regions has important implications on their application as genetic endophenotypes.
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Affiliation(s)
- Saud Alhusaini
- Department of Molecular and Cellular Therapeutics, The Royal College of Surgeons in Ireland, Dublin 2, Ireland
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Stretton J, Thompson PJ. Frontal lobe function in temporal lobe epilepsy. Epilepsy Res 2011; 98:1-13. [PMID: 22100147 PMCID: PMC3398387 DOI: 10.1016/j.eplepsyres.2011.10.009] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 09/02/2011] [Accepted: 10/09/2011] [Indexed: 10/25/2022]
Abstract
Temporal lobe epilepsy (TLE) is typically associated with long-term memory dysfunction. The frontal lobes support high-level cognition comprising executive skills and working memory that is vital for daily life functioning. Deficits in these functions have been increasingly reported in TLE. Evidence from both the neuropsychological and neuroimaging literature suggests both executive function and working memory are compromised in the presence of TLE. In relation to executive impairment, particular focus has been paid to set shifting as measured by the Wisconsin Card Sorting Task. Other discrete executive functions such as decision-making and theory of mind also appear vulnerable but have received little attention. With regard to working memory, the medial temporal lobe structures appear have a more critical role, but with emerging evidence of hippocampal dependent and independent processes. The relative role of underlying pathology and seizure spread is likely to have considerable bearing upon the cognitive phenotype and trajectory in TLE. The identification of the nature of frontal lobe dysfunction in TLE thus has important clinical implications for prognosis and surgical management. Longitudinal neuropsychological and neuroimaging studies assessing frontal lobe function in TLE patients pre- and postoperatively will improve our understanding further.
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Affiliation(s)
- J Stretton
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, UK.
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Scanlon C, Mueller SG, Tosun D, Cheong I, Garcia P, Barakos J, Weiner MW, Laxer KD. Impact of methodologic choice for automatic detection of different aspects of brain atrophy by using temporal lobe epilepsy as a model. AJNR Am J Neuroradiol 2011; 32:1669-76. [PMID: 21852375 DOI: 10.3174/ajnr.a2578] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE VBM, DBM, and cortical thickness measurement techniques are commonly used automated methods to detect structural brain changes based on MR imaging. The goal of this study was to demonstrate the pathology detected by the 3 methods and to provide guidance as to which method to choose for specific research questions. This goal was accomplished by 1) identifying structural abnormalities associated with TLE with (TLE-mts) and without (TLE-no) hippocampal sclerosis, which are known to be associated with different types of brain atrophy, by using these 3 methods; and 2) determining the aspect of the disease pathology identified by each method. MATERIALS AND METHODS T1-weighted MR images were acquired for 15 TLE-mts patients, 14 TLE-no patients, and 33 controls on a high-field 4T scanner. Optimized VBM was carried out by using SPM software, DBM was performed by using a fluid-flow registration algorithm, and cortical thickness was analyzed by using FS-CT. RESULTS In TLE-mts, the most pronounced volume losses were identified in the ipsilateral hippocampus and mesial temporal region, bilateral thalamus, and cerebellum, by using SPM-VBM and DBM. In TLE-no, the most widespread changes were cortical and identified by using FS-CT, affecting the bilateral temporal lobes, insula, and frontal and occipital lobes. DBM revealed 2 clusters of reduced volume complementing FS-CT analysis. SPM-VBM did not show any significant volume losses in TLE-no. CONCLUSIONS These results demonstrate that the 3 methods detect different aspects of brain atrophy and that the choice of the method should be guided by the suspected pathology of the disease.
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Affiliation(s)
- C Scanlon
- Center for Imaging of Neurodegenerative Diseases and Department of Radiology, University of California-San Francisco, CA, USA
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Sloan DM, Zhang D, Bertram EH. Increased GABAergic inhibition in the midline thalamus affects signaling and seizure spread in the hippocampus-prefrontal cortex pathway. Epilepsia 2011; 52:523-30. [PMID: 21204829 PMCID: PMC3058300 DOI: 10.1111/j.1528-1167.2010.02919.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
PURPOSE The midline thalamus is an important component of the circuitry in limbic seizures, but it is unclear how synaptic modulation of the thalamus affects that circuitry. In this study, we wished to understand how synaptic modulation of the thalamus can affect interregional signaling and seizure spread in the limbic network. METHODS We examined the effect of γ-aminobutyric acid (GABA) modulation of the mediodorsal (MD) region of the thalamus on responses in the prefrontal cortex (PFC) by stimulation of the subiculum (SB). Muscimol, a GABA(A) agonist, was injected into the MD, and the effect on local responses to subiculum stimulation was examined. Evoked potentials were induced in the MD and the PFC by low-frequency stimulation of the SB, and seizures were generated in the subiculum by repeated 20-Hz stimulations. The effect of muscimol in the MD on the evoked potentials and seizures was measured. KEY FINDINGS Thalamic responses to stimulation of the subiculum were reduced in the presence of muscimol. Reduction of the amplitudes of evoked potentials in the MD resulted in an attenuation of the late, thalamic components of the responses in the PFC, as well as of seizure durations. SIGNIFICANCE Activation of GABA(A) receptors in the midline thalamus not only causes changes within the thalamus, but it has broader effects on the limbic network. This work provides further evidence that synaptic modulation within the midline thalamus alters system excitability more broadly and reduces seizure activity.
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Affiliation(s)
- David M Sloan
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia 22908, USA
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