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Xiao F, Caciagli L, Wandschneider B, Sone D, Young AL, Vos SB, Winston GP, Zhang Y, Liu W, An D, Kanber B, Zhou D, Sander JW, Thom M, Duncan JS, Alexander DC, Galovic M, Koepp MJ. Identification of different MRI atrophy progression trajectories in epilepsy by subtype and stage inference. Brain 2023; 146:4702-4716. [PMID: 37807084 PMCID: PMC10629797 DOI: 10.1093/brain/awad284] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 06/30/2023] [Accepted: 08/02/2023] [Indexed: 10/10/2023] Open
Abstract
Artificial intelligence (AI)-based tools are widely employed, but their use for diagnosis and prognosis of neurological disorders is still evolving. Here we analyse a cross-sectional multicentre structural MRI dataset of 696 people with epilepsy and 118 control subjects. We use an innovative machine-learning algorithm, Subtype and Stage Inference, to develop a novel data-driven disease taxonomy, whereby epilepsy subtypes correspond to distinct patterns of spatiotemporal progression of brain atrophy.In a discovery cohort of 814 individuals, we identify two subtypes common to focal and idiopathic generalized epilepsies, characterized by progression of grey matter atrophy driven by the cortex or the basal ganglia. A third subtype, only detected in focal epilepsies, was characterized by hippocampal atrophy. We corroborate external validity via an independent cohort of 254 people and confirm that the basal ganglia subtype is associated with the most severe epilepsy.Our findings suggest fundamental processes underlying the progression of epilepsy-related brain atrophy. We deliver a novel MRI- and AI-guided epilepsy taxonomy, which could be used for individualized prognostics and targeted therapeutics.
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Affiliation(s)
- Fenglai Xiao
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Lorenzo Caciagli
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
- Department of Neurology, Inselspital, Sleep-Wake-Epilepsy-Center, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Britta Wandschneider
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
| | - Daichi Sone
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
- Department of Psychiatry, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
| | - Alexandra L Young
- Centre for Medical Image Computing, Departments of Computer Science, Medical Physics, and Biomedical Engineering, UCL, London, WC1E 6BT, UK
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, SE5 8AF, UK
| | - Sjoerd B Vos
- Centre for Medical Image Computing, Departments of Computer Science, Medical Physics, and Biomedical Engineering, UCL, London, WC1E 6BT, UK
- Neuroradiological Academic Unit, UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
- Centre for Microscopy, Characterisation, and Analysis, University of Western Australia, Perth, WA 6009, Australia
| | - Gavin P Winston
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
- Department of Medicine, Division of Neurology, Queen’s University, Kingston, K7L 3N6, Canada
- Centre for Neuroscience Studies, Queen’s University, Kingston, K7L 3N6, Canada
| | - Yingying Zhang
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Wenyu Liu
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Dongmei An
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Baris Kanber
- Centre for Medical Image Computing, Departments of Computer Science, Medical Physics, and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - Dong Zhou
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
| | - Josemir W Sander
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, 610041, China
- Stichting Epilepsie Instellingen Nederland – (SEIN), Heemstede, 2103SW, The Netherlands
| | - Maria Thom
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
| | - John S Duncan
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
| | - Daniel C Alexander
- Centre for Medical Image Computing, Departments of Computer Science, Medical Physics, and Biomedical Engineering, UCL, London, WC1E 6BT, UK
| | - Marian Galovic
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- Department of Neurology, Clinical Neuroscience Center, University Hospital Zurich, Zurich, CH-8091, Switzerland
| | - Matthias J Koepp
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, WC1N 3BG, UK
- UCL-Epilepsy Society MRI Unit, Chalfont Centre for Epilepsy, Chalfont St Peter, Buckinghamshire, SL9 0RJ, UK
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2
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Kilpattu Ramaniharan A, Zhang MW, Selladurai G, Martin R, Ver Hoef L. Loss of hippocampal dentation in hippocampal sclerosis and its relationship to memory dysfunction. Epilepsia 2022; 63:1104-1114. [PMID: 35243619 DOI: 10.1111/epi.17211] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Hippocampal dentation (HD) is a "tooth-like" morphological feature observed on the inferior aspect of the human hippocampus. It has been found that HD varies dramatically in healthy adults and is positively associated with verbal and visual memory. In this work, we evaluate the loss of HD and its association to memory dysfunction in patients with temporal lobe epilepsy who have hippocampal sclerosis (HS). METHODS 58 unilateral HS patients with neuropsychological data were identified from a retrospective database. T1w MPRAGE images (~1mm resolution) were upsampled to 0.25mm and were processed using ASHS software to obtain ultra high resolution segmentations and 3D renderings. Dentes were counted on the epileptic and contralateral sides, and associations were tested between dentation on the epileptic versus contralateral sides and measures of verbal and visuospatial memory with respect to the dominant versus non-dominant hemisphere. RESULTS The median number of dentes in epileptic hippocampi was significantly lower than in contralateral hippocampi (p<0.0001). Among cases with HS in the dominant hemisphere, verbal memory was significantly correlated with contralateral non-dominant hemisphere dentation (r = 0.45, p = 0.02). Similarly, among cases of HS in the non-dominant hemisphere, visual memory was significantly correlated with contralateral dominant hemisphere dentation (r = 0.50, p = 0.03). All other analyses were not significant. SIGNIFICANCE This is the first study characterizing dentation in TLE patients with HS and its memory correlates. There is marked loss of dentation in sclerotic hippocampi compared to the unaffected contralateral hippocampi. Material-specific measures of memory performance are paradoxically correlated with dentation contralateral to the side with HS, suggesting that contralateral functional capacity explains some of the variation in memory across TLE patients. Hippocampal dentation is an important variable to consider in understanding memory loss in TLE.
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Affiliation(s)
| | - Mike Weng Zhang
- University of Alabama at Birmingham, Department of Neurology, Birmingham, Alabama, USA
| | - Goutham Selladurai
- University of Alabama at Birmingham, Department of Neurology, Birmingham, Alabama, USA
| | - Roy Martin
- University of Alabama at Birmingham, Department of Neurology, Birmingham, Alabama, USA
| | - Lawrence Ver Hoef
- University of Alabama at Birmingham, Department of Neurology, Birmingham, Alabama, USA.,Baptist Health Medical Group, Department of Neurology, Louisville, Kentucky, USA
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3
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Gleichgerrcht E, Munsell B, Keller SS, Drane DL, Jensen JH, Spampinato MV, Pedersen NP, Weber B, Kuzniecky R, McDonald C, Bonilha L. Radiological identification of temporal lobe epilepsy using artificial intelligence: a feasibility study. Brain Commun 2021; 4:fcab284. [PMID: 35243343 PMCID: PMC8887904 DOI: 10.1093/braincomms/fcab284] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 09/29/2021] [Accepted: 10/04/2021] [Indexed: 12/15/2022] Open
Abstract
Temporal lobe epilepsy is associated with MRI findings reflecting underlying mesial temporal sclerosis. Identifying these MRI features is critical for the diagnosis and management of temporal lobe epilepsy. To date, this process relies on visual assessment by highly trained human experts (e.g. neuroradiologists, epileptologists). Artificial intelligence is increasingly recognized as a promising aid in the radiological evaluation of neurological diseases, yet its applications in temporal lobe epilepsy have been limited. Here, we applied a convolutional neural network to assess the classification accuracy of temporal lobe epilepsy based on structural MRI. We demonstrate that convoluted neural networks can achieve high accuracy in the identification of unilateral temporal lobe epilepsy cases even when the MRI had been originally interpreted as normal by experts. We show that accuracy can be potentiated by employing smoothed grey matter maps and a direct acyclic graphs approach. We further discuss the foundations for the development of computer-aided tools to assist with the diagnosis of epilepsy.
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Affiliation(s)
- Ezequiel Gleichgerrcht
- Department of Neurology, Medical University of South
Carolina, Charleston, SC 29425, USA
| | - Brent Munsell
- Department of Computer Science, University of North
Carolina, Chapel Hill, NC 27599, USA
- Department of Psychiatry, University of North
Carolina, Chapel Hill, NC 27599, USA
| | - Simon S Keller
- Institute of Systems, Molecular and Integrative
Biology, University of Liverpool, Liverpool L69 7BE, UK
- The Walton Centre NHS Foundation
Trust, Liverpool L9 7LJ, UK
| | - Daniel L Drane
- Department of Neurology, Emory
University, Atlanta, GA 30322, USA
| | - Jens H Jensen
- Center for Biomedical Imaging, Medical University of
South Carolina, Charleston, SC 29425, USA
| | - M Vittoria Spampinato
- Department of Radiology, Medical University of South
Carolina, Charleston, SC 29425, USA
| | - Nigel P Pedersen
- Department of Neurology, Emory
University, Atlanta, GA 30322, USA
| | - Bernd Weber
- Institute of Experimental Epileptology and Cognition
Research, University of Bonn, Bonn 53113, Germany
| | - Ruben Kuzniecky
- Department of Neurology, Hofstra
University/Northwell, New York, NY 10075, USA
| | - Carrie McDonald
- Department of Psychiatry, University of California
San Diego, La Jolla, CA 92093, USA
| | - Leonardo Bonilha
- Department of Neurology, Medical University of South
Carolina, Charleston, SC 29425, USA
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4
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Kang E, Kang M, Ju Y, Lee SJ, Lee YS, Woo DC, Sung YH, Baek IJ, Shim WH, Son WC, Choi IH, Seo EJ, Yoo HW, Han YM, Lee BH. Association between ARID2 and RAS-MAPK pathway in intellectual disability and short stature. J Med Genet 2021; 58:767-777. [PMID: 33051312 DOI: 10.1136/jmedgenet-2020-107111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 08/03/2020] [Accepted: 08/26/2020] [Indexed: 12/29/2022]
Abstract
BACKGROUND ARID2 belongs to the Switch/sucrose non-fermenting complex, in which the genetic defects have been found in patients with dysmorphism, short stature and intellectual disability (ID). As the phenotypes of patients with ARID2 mutations partially overlap with those of RASopathy, this study evaluated the biochemical association between ARID2 and RAS-MAPK pathway. METHODS The phenotypes of 22 patients with either an ARID2 heterozygous mutation or haploinsufficiency were reviewed. Comprehensive molecular analyses were performed using somatic and induced pluripotent stem cells (iPSCs) of a patient with ARID2 haploinsufficiency as well as using the mouse model of Arid2 haploinsufficiency by CRISPR/Cas9 gene editing. RESULTS The phenotypic characteristics of ARID2 deficiency include RASopathy, Coffin-Lowy syndrome or Coffin-Siris syndrome or undefined syndromic ID. Transient ARID2 knockout HeLa cells using an shRNA increased ERK1 and ERK2 phosphorylation. Impaired neuronal differentiation with enhanced RAS-MAPK activity was observed in patient-iPSCs. In addition, Arid2 haploinsufficient mice exhibited reduced body size and learning/memory deficit. ARID2 haploinsufficiency was associated with reduced IFITM1 expression, which interacts with caveolin-1 (CAV-1) and inhibits ERK activation. DISCUSSION ARID2 haploinsufficiency is associated with enhanced RAS-MAPK activity, leading to reduced IFITM1 and CAV-1 expression, thereby increasing ERK activity. This altered interaction might lead to abnormal neuronal development and a short stature.
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Affiliation(s)
- Eungu Kang
- Department of Pediatrics, Korea University Ansan Hospital, Ansan, Gyeonggi-do, Republic of Korea
| | - Minji Kang
- Asan institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Younghee Ju
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Sang-Joon Lee
- Asan institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yong-Seok Lee
- Department of Physiology, Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Dong-Cheol Woo
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Young Hoon Sung
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Convergence Medicine, Bio-Medical Institute of Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - In-Jeoung Baek
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Convergence Medicine, Bio-Medical Institute of Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Woo Hyun Shim
- Department of Medical Science, Asan Medical Institute of Convergence Science and Technology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Woo-Chan Son
- Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - In Hee Choi
- Medical Genetics Center, Asan Medical Center, Seoul, Republic of Korea
| | - Eul-Ju Seo
- Medical Genetics Center, Asan Medical Center, Seoul, Republic of Korea
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Han-Wook Yoo
- Medical Genetics Center, Asan Medical Center, Seoul, Republic of Korea
- Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yong-Mahn Han
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Beom Hee Lee
- Medical Genetics Center, Asan Medical Center, Seoul, Republic of Korea
- Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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5
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Deleo F, Hong SJ, Fadaie F, Caldairou B, Krystal S, Bernasconi N, Bernasconi A. Whole-brain multimodal MRI phenotyping of periventricular nodular heterotopia. Neurology 2020; 95:e2418-e2426. [PMID: 32817185 DOI: 10.1212/wnl.0000000000010648] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/26/2020] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE To test the hypothesis that in periventricular nodular heterotopia (PVNH) structure and function of cortical areas overlying the heterotopic gray matter are preferentially affected. METHODS We studied a group of 40 patients with PVNH and normal-appearing cortex and compared their quantitative MRI markers of brain development, structure, and function to those of 43 age- and sex-matched healthy controls. Inspired by models of neocortical development suggesting that neuronal migration follows a curvilinear path to preserve topologic correspondence between the outer ventricular zone and the cortical surface, we computationally defined the overlying cortex using the Laplace equation and generated synthetic streamlines that link the ventricles, where nodules are located, and the neocortex. RESULTS We found multilobar cortical thickening encompassing prefrontal, latero-basal temporal, and temporoparietal cortices largely corresponding with the PVNH group-averaged map of the overlying cortex, the latter colocalized with areas of abnormal function, as defined by resting-state fMRI. Patients also presented hippocampal functional hyperconnectivity and malrotation, the latter positively correlating with neocortical maldevelopment indexed by increased folding complexity of the parahippocampus. In clusters of thickness and curvature findings, there were no significant differences between unilateral and bilateral PVNH; contrasting brain-wide metrics between cohorts was also unrevealing. There was no relationship between imaging markers and disease duration except for positive correlation with functional anomalies. CONCLUSION Our quantitative image analysis demonstrates widespread structural and functional alterations in PVNH with differential interaction with the overlying cortex and the hippocampus. Right hemispheric predominance may be explained by an early insult, likely genetically determined, on brain morphogenesis.
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Affiliation(s)
- Francesco Deleo
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Seok-Jun Hong
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Fatemeh Fadaie
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Benoit Caldairou
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Sidney Krystal
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Neda Bernasconi
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Andrea Bernasconi
- From the Neuroimaging of Epilepsy Laboratory (F.D., S.-J.H., F.F., B.C., S.K., N.B., A.B.), Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada; and Epilepsy Unit (F.D.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
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6
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Yoo JG, Jakabek D, Ljung H, Velakoulis D, van Westen D, Looi JCL, Källén K. MRI morphology of the hippocampus in drug-resistant temporal lobe epilepsy: Shape inflation of left hippocampus and correlation of right-sided hippocampal volume and shape with visuospatial function in patients with right-sided TLE. J Clin Neurosci 2019; 67:68-74. [PMID: 31221579 DOI: 10.1016/j.jocn.2019.06.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/10/2019] [Indexed: 11/27/2022]
Abstract
We sought to quantify the morphology in vivo of hippocampi in patients with drug resistant temporal lobe epilepsy (TLE) via magnetic resonance imaging (MRI), prior to temporal lobe resection, and the correlation of surface-based shape analysis of morphology and clinical cognitive function. Thirty patients with drug-resistant TLE and twenty healthy controls underwent clinical neuropsychological testing, and brain MRI at Lund University Hospital prior to hippocampal resection. A neuroradiologist categorised radiological findings into normal hippocampus, subtle changes or definite hippocampal sclerosis. We manually segmented MRI of the hippocampus of participants using ANALYZE 11.0 software; and analysed hippocampal shape using SPHARM-PDM software. For radiologist visual-ratings of definite left hippocampal sclerosis in those with left-sided TLE, hippocampal volumes were significantly smaller compared to normal controls. In right-sided TLE we found contralateral shape inflation of the left hippocampus, partially confirming previous shape analytic studies of the hippocampus in TLE. We found significant correlation of volume and surface deflation of the right hippocampus in right-sided TLE with reduced performance on the two right-lateralised visuospatial memory tests, the Rey Complex Figure Test (Immediate and Delayed recall) and the Recognition Memory Test for faces. Decreased hippocampal volume was correlated with poorer performance on these tasks. The morphology of the hippocampus can be quantified via neuroimaging shape analysis in TLE. Contralateral shape inflation of the left hippocampus in right-sided TLE is intriguing, and may result from functional compensation and/or abnormal tissue. In right-sided TLE, hippocampal structural integrity, quantified as hippocampal shape, is correlated with lateralised visuospatial function.
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Affiliation(s)
- Jae-Gon Yoo
- Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra Hospital, ACT, Australia
| | - David Jakabek
- Graduate School of Medicine, University of Wollongong, Wollongong, NSW, Australia
| | - Hanna Ljung
- Skåne University Hospital, Department of Neurology and Rehabilitation Medicine, Lund, Sweden
| | - Dennis Velakoulis
- Neuropsychiatry Unit, Royal Melbourne Hospital, Department of Psychiatry, University of Melbourne Medical School, Melbourne, Victoria, Australia
| | - Danielle van Westen
- Diagnostic Radiology, Department of Clinical Sciences, Lund University, Lund, Sweden; Image and Function, Skane University Hospital, Lund, Sweden
| | - Jeffrey C L Looi
- Academic Unit of Psychiatry and Addiction Medicine, Australian National University Medical School, Canberra Hospital, ACT, Australia; Neuropsychiatry Unit, Royal Melbourne Hospital, Department of Psychiatry, University of Melbourne Medical School, Melbourne, Victoria, Australia.
| | - Kristina Källén
- Division of Clinical Sciences, Helsingborg, Sweden & Department of Clinical Sciences, Lund, Sweden; Neurology, Lund, Sweden & Faculty of Medicine, Lund University, Lund, Sweden
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7
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Adler S, Blackwood M, Northam GB, Gunny R, Hong SJ, Bernhardt BC, Bernasconi A, Bernasconi N, Jacques T, Tisdall M, Carmichael DW, Cross JH, Baldeweg T. Multimodal computational neocortical anatomy in pediatric hippocampal sclerosis. Ann Clin Transl Neurol 2018; 5:1200-1210. [PMID: 30349855 PMCID: PMC6186946 DOI: 10.1002/acn3.634] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 08/01/2018] [Indexed: 12/16/2022] Open
Abstract
Objective In contrast to adult cohorts, neocortical changes in epileptic children with hippocampal damage are not well characterized. Here, we mapped multimodal neocortical markers of epilepsy‐related structural compromise in a pediatric cohort of temporal lobe epilepsy and explored how they relate to clinical factors. Methods We measured cortical thickness, gray–white matter intensity contrast and intracortical FLAIR intensity in 22 patients with hippocampal sclerosis (HS) and 30 controls. Surface‐based linear models assessed between‐group differences in morphological and MR signal intensity markers. Structural integrity of the hippocampus was measured by quantifying atrophy and FLAIR patterns. Linear models were used to evaluate the relationships between hippocampal and neocortical MRI markers and clinical factors. Results In the hippocampus, patients demonstrated ipsilateral atrophy and bilateral FLAIR hyperintensity. In the neocortex, patients showed FLAIR signal hyperintensities and gray–white matter boundary blurring in the ipsilesional mesial and lateral temporal neocortex. In contrast, cortical thinning was minimal and restricted to a small area of the ipsilesional temporal pole. Furthermore, patients with a history of febrile convulsions demonstrated more pronounced FLAIR hyperintensity in the ipsilesional temporal neocortex. Interpretation Pediatric HS patients do not yet demonstrate the widespread cortical thinning present in adult cohorts, which may reflect consequences of a protracted disease process. However, pronounced temporal neocortical FLAIR hyperintensity and blurring of the gray–white matter boundary are already detectable, suggesting that alterations in MR signal intensities may reflect a different underlying pathophysiology that is detectable earlier in the disease and more pervasive in patients with a history of febrile convulsions.
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Affiliation(s)
- Sophie Adler
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Great Ormond Street Hospital for Children London United Kingdom
| | - Mallory Blackwood
- Institute of Neurology University College London London United Kingdom
| | - Gemma B Northam
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom
| | - Roxana Gunny
- Great Ormond Street Hospital for Children London United Kingdom
| | - Seok-Jun Hong
- Neuroimaging of Epilepsy Laboratory McConnell Brain Imaging Centre Montreal Neurological Institute and Hospital McGill University Montreal Quebec Canada
| | - Boris C Bernhardt
- Multimodal Imaging and Connectome Analysis Lab McConnell Brain Imaging Centre Montreal Neurological Institute McGill University Montreal Quebec Canada
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory McConnell Brain Imaging Centre Montreal Neurological Institute and Hospital McGill University Montreal Quebec Canada
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory McConnell Brain Imaging Centre Montreal Neurological Institute and Hospital McGill University Montreal Quebec Canada
| | - Thomas Jacques
- Developmental Biology and Cancer Programme UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Department of Histopathology Great Ormond Street Hospital for Children NHS Foundation Trust London United Kingdom
| | - Martin Tisdall
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Great Ormond Street Hospital for Children London United Kingdom
| | - David W Carmichael
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Great Ormond Street Hospital for Children London United Kingdom
| | - J Helen Cross
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Great Ormond Street Hospital for Children London United Kingdom
| | - Torsten Baldeweg
- Developmental Neurosciences UCL Great Ormond Street Institute of Child Health University College London London United Kingdom.,Great Ormond Street Hospital for Children London United Kingdom
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8
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Kim H, Kim JH, Possin KL, Winer J, Geschwind MD, Xu D, Hess CP. Surface-based morphometry reveals caudate subnuclear structural damage in patients with premotor Huntington disease. Brain Imaging Behav 2018; 11:1365-1372. [PMID: 27730480 DOI: 10.1007/s11682-016-9616-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In patients with premotor Huntington's disease (pmHD), literature has reported decreases in caudate volume. However, the regional vulnerability of the caudate nucleus to pmHD remains to be clarified. We aimed to determine whether regional structural damage of the caudate nucleus was present in pmHD and was correlated with clinical profile using a surface-based morphometric technique applied to T1-weighted MRI. The study cohort consisted of 14 volunteers with genetically confirmed pmHD (6 males; 41.8 ± 13.2 years) and 11 age- and sex-matched controls (5 males; 46.2 ± 11.9 years, p > 0.3). On 3-T T1-weighted images, bilateral caudate volumes were manually delineated. The resulting labels were converted to a surface, triangulated with 1002 points equally distributed across subjects using SPHARM-PDM. Displacement vectors were then computed between each individual and a template surface representing the whole cohort. Computing point-wise Jacobian determinants (JD) from these vectors quantified local volumes. We found decreases in bilateral global caudate volumes in the pmHD group compared to controls (t = 3.4; p = 0.002). Point-wise analysis of local volumes mapped caudate atrophy in pmHD primarily onto medial surface (t > 2.7; FDR < 0.05), with most pronounced changes in anteromedial subdivision. In a combined group of patients and controls, volume within the area presenting significant group difference was positively correlated with scores of executive function (r = 0.7; p < 0.001) and working memory (r = 0.6; p = 0.002). In patients, the caudate atrophy was associated with increase in disease burden (r = 0.7; p = 0.005). Caudate subnuclear atrophy measured using our surface-based morphometric technique is evident in pmHD, correlates with clinical variables, and may provide a more sensitive biomarker than global volumes.
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Affiliation(s)
- Hosung Kim
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.
| | - Ji-Hoon Kim
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.,Department of Radiology, Seoul National Univeristy Hospital, Seoul, South Korea
| | - Katherine L Possin
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Joseph Winer
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Michael D Geschwind
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Duan Xu
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA
| | - Christopher P Hess
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA, USA.,Department of Neurology, University of California San Francisco, San Francisco, CA, USA
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9
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Egocentric and allocentric visuospatial working memory in premotor Huntington's disease: A double dissociation with caudate and hippocampal volumes. Neuropsychologia 2017; 101:57-64. [PMID: 28427989 DOI: 10.1016/j.neuropsychologia.2017.04.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 03/21/2017] [Accepted: 04/15/2017] [Indexed: 12/13/2022]
Abstract
Our brains represent spatial information in egocentric (self-based) or allocentric (landmark-based) coordinates. Rodent studies have demonstrated a critical role for the caudate in egocentric navigation and the hippocampus in allocentric navigation. We administered tests of egocentric and allocentric working memory to individuals with premotor Huntington's disease (pmHD), which is associated with early caudate nucleus atrophy, and controls. Each test had 80 trials during which subjects were asked to remember 2 locations over 1-sec delays. The only difference between these otherwise identical tests was that locations could only be coded in self-based or landmark-based coordinates. We applied a multiatlas-based segmentation algorithm and computed point-wise Jacobian determinants to measure regional variations in caudate and hippocampal volumes from 3T MRI. As predicted, the pmHD patients were significantly more impaired on egocentric working memory. Only egocentric accuracy correlated with caudate volumes, specifically the dorsolateral caudate head, right more than left, a region that receives dense efferents from dorsolateral prefrontal cortex. In contrast, only allocentric accuracy correlated with hippocampal volumes, specifically intermediate and posterior regions that connect strongly with parahippocampal and posterior parietal cortices. These results indicate that the distinction between egocentric and allocentric navigation applies to working memory. The dorsolateral caudate is important for egocentric working memory, which can explain the disproportionate impairment in pmHD. Allocentric working memory, in contrast, relies on the hippocampus and is relatively spared in pmHD.
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10
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Sone D, Sato N, Maikusa N, Ota M, Sumida K, Yokoyama K, Kimura Y, Imabayashi E, Watanabe Y, Watanabe M, Okazaki M, Onuma T, Matsuda H. Automated subfield volumetric analysis of hippocampus in temporal lobe epilepsy using high-resolution T2-weighed MR imaging. NEUROIMAGE-CLINICAL 2016; 12:57-64. [PMID: 27489767 PMCID: PMC4960104 DOI: 10.1016/j.nicl.2016.06.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 06/07/2016] [Accepted: 06/11/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND PURPOSE Automated subfield volumetry of hippocampus is desirable for use in temporal lobe epilepsy (TLE), but its utility has not been established. Automatic segmentation of hippocampal subfields (ASHS) and the new version of FreeSurfer software (ver.6.0) using high-resolution T2-weighted MR imaging are candidates for this volumetry. The aim of this study was to evaluate hippocampal subfields in TLE patients using ASHS as well as the old and new versions of FreeSurfer. MATERIALS AND METHODS We recruited 50 consecutive unilateral TLE patients including 25 with hippocampal sclerosis (TLE-HS) and 25 without obvious etiology (TLE-nonHS). All patients and 45 healthy controls underwent high-resolution T2-weighted and 3D-volume T1-weighted MRI scanning. We analyzed all of their MR images by FreeSurfer ver.5.3, ver.6.0 and ASHS. For each subfield, normalized z-scores were calculated and compared among groups. RESULTS In TLE-HS groups, ASHS and FreeSurfer ver.6.0 revealed maximal z-scores in ipsilateral cornu ammonis (CA) 1, CA4 and dentate gyrus (DG), whereas in FreeSurfer ver.5.3 ipsilateral subiculum showed maximal z-scores. In TLE-nonHS group, there was no significant volume reduction by either ASHS or FreeSurfer. CONCLUSIONS ASHS and the new version of FreeSurfer may have an advantage in compatibility with existing histopathological knowledge in TLE patients with HS compared to the old version of FreeSurfer (ver.5.3), although further investigations with pathological findings and/or surgical outcomes are desirable.
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Affiliation(s)
- Daichi Sone
- Department of Radiology, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan; Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo, Tokyo 113-8654, Japan
| | - Noriko Sato
- Department of Radiology, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Norihide Maikusa
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Miho Ota
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Kaoru Sumida
- Department of Radiology, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Kota Yokoyama
- Department of Radiology, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Yukio Kimura
- Department of Radiology, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Etsuko Imabayashi
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Yutaka Watanabe
- Department of Psychiatry, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Masako Watanabe
- Department of Psychiatry, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Mitsutoshi Okazaki
- Department of Psychiatry, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
| | - Teiichi Onuma
- Musashino-Kokubunji Clinic, 4-1-9-3, Honcho, Kokubunji, Tokyo 185-0012, Japan
| | - Hiroshi Matsuda
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8551, Japan
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Leach JL, Awwad R, Greiner HM, Vannest JJ, Miles L, Mangano FT. Mesial temporal lobe morphology in intractable pediatric epilepsy: so-called hippocampal malrotation, associated findings, and relevance to presurgical assessment. J Neurosurg Pediatr 2016; 17:683-93. [PMID: 26870898 DOI: 10.3171/2015.11.peds15485] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Diagnostic criteria for hippocampal malrotation (HIMAL) on brain MRI typically include a rounded hippocampus, vertical collateral sulcus, and architectural blurring. Relationship to epileptogenesis remains speculative, and usefulness for surgical guidance is unknown. The study was performed to determine the prevalence of hippocampal rotational anomalies in a cohort of pediatric patients with intractable epilepsy undergoing evaluation for surgery and to determine the significance of this finding in the context of surgical planning. METHODS Forty-eight surgically treated children with intractable epilepsy were compared with matched healthy subjects; reviewers were blinded to surgical side. Each temporal lobe was evaluated for rounded hippocampus, blurring, vertical collateral sulcus, wide choroidal fissure, enlarged temporal horn, low fornix, hippocampal signal, and findings of hippocampal sclerosis. A mesial temporal lobe (MTL) score was calculated by summing the number of features, and the collateral sulcus angle (CSA) was measured in each temporal lobe. Surgical side, pathological diagnosis, and imaging findings elsewhere in the brain were tabulated. Presence of HIMAL, associated imaging features, and MTL score were compared between sides, between epilepsy and control groups, in relationship to side of surgery, and in relationship to postoperative outcome. RESULTS Only 3 epilepsy patients (6.2%) and no controls exhibited all 3 features of HIMAL (p = 0.12). Eight of 48 (16.7%) epilepsy versus 2 of 48 (4.6%) control subjects had both a rounded hippocampus and vertical collateral sulcus (suggesting HIMAL) (p = 0.045). In control and epilepsy subjects, most findings were more prevalent on the left, and the left CSA was more vertical (p < 0.0001). Epilepsy subjects had higher MTL scores (z = -2.95, p = 0.002) and more acute CSAs (p = 0.04) than controls. Only lateralizing raw MTL score had a significant association with surgical side (p = 0.03, OR 7.33); however, this was not significant when hippocampal sclerosis cases were excluded. HIMAL findings were more prevalent and MTL scores were higher in patients with resections involving the temporal lobes. On group analysis, HIMAL findings did not predict eventual surgical side and did not predict outcome, although the numbers are small. In 4 patients the abnormally rotated hippocampus was resected and showed hippocampal sclerosis and/or dysplastic changes on histopathology. All of these patients had a good outcome after surgery. CONCLUSIONS While increased in prevalence in children with intractable epilepsy, imaging findings of HIMAL did not have preoperative lateralizing utility in this group. Findings of HIMAL (including round hippocampus, architectural blurring, and vertical collateral sulcus) did not predict outcome after surgery, although the small number of patients with these findings limits evaluation. In the small number of patients in which the malrotated hippocampus was removed, outcome was good. Further research is needed to continue to define this association in children with intractable epilepsy, focusing on a temporal lobe cohort.
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Affiliation(s)
| | | | | | | | - Lili Miles
- Pathology, Comprehensive Epilepsy Treatment Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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12
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Scott JA, Goodrich-Hunsaker N, Kalish K, Lee A, Hunsaker MR, Schumann CM, Carmichael OT, Simon TJ. The hippocampi of children with chromosome 22q11.2 deletion syndrome have localized anterior alterations that predict severity of anxiety. J Psychiatry Neurosci 2016; 41:203-13. [PMID: 26599134 PMCID: PMC4853211 DOI: 10.1503/jpn.140299] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Individuals with 22q11.2 deletion syndrome (22q11.2DS) have an elevated risk for schizophrenia, which increases with history of childhood anxiety. Altered hippocampal morphology is a common neuroanatomical feature of 22q11.2DS and idiopathic schizophrenia. Relating hippocampal structure in children with 22q11.2DS to anxiety and impaired cognitive ability could lead to hippocampus-based characterization of psychosis-proneness in this at-risk population. METHODS We measured hippocampal volume using a semiautomated approach on MRIs collected from typically developing children and children with 22q11.2DS. We then analyzed hippocampal morphology with Localized Components Analysis. We tested the modulating roles of diagnostic group, hippocampal volume, sex and age on local hippocampal shape components. Lastly, volume and shape components were tested as covariates of IQ and anxiety. RESULTS We included 48 typically developing children and 69 children with 22q11.2DS in our study. Hippocampal volume was reduced bilaterally in children with 22q11.2DS, and these children showed greater variation in the shape of the anterior hippocampus than typically developing children. Children with 22q11.2DS had greater inward deformation of the anterior hippocampus than typically developing children. Greater inward deformation of the anterior hippocampus was associated with greater severity of anxiety, specifically fear of physical injury, within the 22q11.2DS group. LIMITATIONS Shape alterations are not specific to hippocampal subfields. CONCLUSION Alterations in the structure of the anterior hippocampus likely affect function and may impact limbic circuitry. We suggest these alterations potentially contribute to anxiety symptoms in individuals with 22q11.2DS through modulatory pathways. Altered hippocampal morphology may be uniquely linked to anxiety risk factors for schizophrenia, which could be a powerful neuroanatomical marker of schizophrenia risk and hence protection.
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Affiliation(s)
- Julia A. Scott
- Correspondence to: J.A. Scott, Center for Neuroscience, 1544 Newton Court, University of California, Davis CA, United States;
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13
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Computational analysis in epilepsy neuroimaging: A survey of features and methods. NEUROIMAGE-CLINICAL 2016; 11:515-529. [PMID: 27114900 PMCID: PMC4833048 DOI: 10.1016/j.nicl.2016.02.013] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 02/11/2016] [Accepted: 02/22/2016] [Indexed: 12/15/2022]
Abstract
Epilepsy affects 65 million people worldwide, a third of whom have seizures that are resistant to anti-epileptic medications. Some of these patients may be amenable to surgical therapy or treatment with implantable devices, but this usually requires delineation of discrete structural or functional lesion(s), which is challenging in a large percentage of these patients. Advances in neuroimaging and machine learning allow semi-automated detection of malformations of cortical development (MCDs), a common cause of drug resistant epilepsy. A frequently asked question in the field is what techniques currently exist to assist radiologists in identifying these lesions, especially subtle forms of MCDs such as focal cortical dysplasia (FCD) Type I and low grade glial tumors. Below we introduce some of the common lesions encountered in patients with epilepsy and the common imaging findings that radiologists look for in these patients. We then review and discuss the computational techniques introduced over the past 10 years for quantifying and automatically detecting these imaging findings. Due to large variations in the accuracy and implementation of these studies, specific techniques are traditionally used at individual centers, often guided by local expertise, as well as selection bias introduced by the varying prevalence of specific patient populations in different epilepsy centers. We discuss the need for a multi-institutional study that combines features from different imaging modalities as well as computational techniques to definitively assess the utility of specific automated approaches to epilepsy imaging. We conclude that sharing and comparing these different computational techniques through a common data platform provides an opportunity to rigorously test and compare the accuracy of these tools across different patient populations and geographical locations. We propose that these kinds of tools, quantitative imaging analysis methods and open data platforms for aggregating and sharing data and algorithms, can play a vital role in reducing the cost of care, the risks of invasive treatments, and improve overall outcomes for patients with epilepsy. We introduce common epileptogenic lesions encountered in patients with drug resistant epilepsy. We discuss state of the art computational techniques used to detect lesions. There is a need for multi-institutional studies that combine these techniques. Clinically validated pipelines alongside the advances in imaging and electrophysiology will improve outcomes.
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Key Words
- DRE, drug resistant epilepsy
- DTI, diffusion tensor imaging
- DWI, diffusion weighted imaging
- Drug resistant epilepsy
- Epilepsy
- FCD, focal cortical dysplasia
- FLAIR, fluid-attenuated inversion recovery
- Focal cortical dysplasia
- GM, gray matter
- GW, gray-white junction
- HARDI, high angular resolution diffusion imaging
- MEG, magnetoencephalography
- MRS, magnetic resonance spectroscopy imaging
- Machine learning
- Malformations of cortical development
- Multimodal neuroimaging
- PET, positron emission tomography
- PNH, periventricular nodular heterotopia
- SBM, surface-based morphometry
- T1W, T1-weighted MRI
- T2W, T2-weighted MRI
- VBM, voxel-based morphometry
- WM, white matter
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14
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Kim H, Gano D, Ho ML, Guo XM, Unzueta A, Hess C, Ferriero DM, Xu D, Barkovich AJ. Hindbrain regional growth in preterm newborns and its impairment in relation to brain injury. Hum Brain Mapp 2015; 37:678-88. [PMID: 26589992 DOI: 10.1002/hbm.23058] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/28/2015] [Accepted: 11/06/2015] [Indexed: 11/08/2022] Open
Abstract
Premature birth globally affects about 11.1% of all newborns and is a risk factor for neurodevelopmental disability in surviving infants. Histology has suggested that hindbrain subdivisions grow differentially, especially in the third trimester. Prematurity-related brain injuries occurring in this period may selectively affect more rapidly developing areas of hindbrain, thus accompanying region-specific impairments in growth and ultimately neurodevelopmental deficits. The current study aimed to quantify regional growth of the cerebellum and the brainstem in preterm neonates (n = 65 with individually multiple scans). We probed associations of the regional volumes with severity of brain injury. In neonates with no imaging evidence of injury, our analysis using a mixed-effect linear model showed faster growth in the pons and the lateral convexity of anterior/posterior cerebellar lobes. Different patterns of growth impairment were found in relation to early cerebral intraventricular hemorrhage and cerebellar hemorrhage (P < 0.05), likely explaining different mechanisms through which neurogenesis is disrupted. The pattern of cerebellar growth identified in our study agreed excellently with details of cerebellar morphogenesis in perinatal development, which has only been observed in histological data. Our proposed analytic framework may provide predictive imaging biomarkers for neurodevelopmental outcome, enabling early identification and treatment of high-risk patients. Hum Brain Mapp 37:678-688, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Hosung Kim
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Dawn Gano
- Department of Pediatrics, University of California, San Francisco, California
| | - Mai-Lan Ho
- Department of Radiollogy, Mayo Clinic, Rochester, MN
| | - Xiaoyue M Guo
- Department of Neurology, University of California, San Francisco, California
| | - Alisa Unzueta
- Department of Neurology, University of California, San Francisco, California
| | - Christopher Hess
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - Donna M Ferriero
- Department of Pediatrics, University of California, San Francisco, California.,Department of Neurology, University of California, San Francisco, California
| | - Duan Xu
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California
| | - A James Barkovich
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, California.,Department of Neurology, University of California, San Francisco, California
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15
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MRI characterization of temporal lobe epilepsy using rapidly measurable spatial indices with hemisphere asymmetries and gender features. Neuroradiology 2015; 57:873-86. [PMID: 26032924 DOI: 10.1007/s00234-015-1540-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/04/2015] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The paucity of morphometric markers for hemispheric asymmetries and gender variations in hippocampi and amygdalae in temporal lobe epilepsy (TLE) calls for better characterization of TLE by finding more useful prognostic MRI parameter(s). METHODS T1-weighted MRI (3 T) morphometry using multiple parameters of hippocampus-parahippocampus (angular and linear measures, volumetry) and amygdalae (volumetry) including their hemispheric asymmetry indices (AI) were evaluated in both genders. The cutoff values of parameters were statistically estimated from measurements of healthy subjects to characterize TLE (57 patients, 55% male) alterations. RESULTS TLE had differential categories with hippocampal atrophy, parahippocampal angle (PHA) acuteness, and several other parametric changes. Bilateral TLE categories were much more prevalent compared to unilateral TLE categories. Female patients were considerably more disposed to bilateral TLE categories than male patients. Male patients displayed diverse categories of unilateral abnormalities. Few patients (both genders) had combined bilateral appearances of hippocampal atrophy, amygdala atrophy, PHA acuteness, and increase in hippocampal angle (HA) where medial distance ratio (MDR) varied among genders. TLE had gender-specific and hemispheric dominant alterations in AI of parameters. Maximum magnitude of parametric changes in TLE includes (a) AI increase in HA of both genders, (b) HA increase (bilateral) in female patients, and (c) increase in ratio of amygdale/hippocampal volume (unilateral, right hemispheric), and AI decrease in MDR, in male patients. CONCLUSION Multiparametric MRI studies of hippocampus and amygdalae, including their hemispheric asymmetry, underscore better characterization of TLE. Rapidly measurable single-slice parameters (HA, PHA, MDR) can readily delineate TLE in a time-constrained clinical setting, which contrasts with customary three-dimensional hippocampal volumetry that requires many slice computation.
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16
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Maccotta L, Moseley ED, Benzinger TL, Hogan RE. Beyond the CA1 subfield: Local hippocampal shape changes in MRI-negative temporal lobe epilepsy. Epilepsia 2015; 56:780-8. [PMID: 25809286 DOI: 10.1111/epi.12955] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2015] [Indexed: 01/05/2023]
Abstract
OBJECTIVE Hippocampal atrophy in temporal lobe epilepsy (TLE) can indicate mesial temporal sclerosis and predict surgical success. Yet many patients with TLE do not have significant atrophy (magnetic resonance imaging (MRI) negative), which presents a diagnostic challenge. We used a new variant of high-dimensional large-deformation mapping to assess whether patients with apparently normal hippocampi have local shape changes that mirror those of patients with significant hippocampal atrophy. METHODS Forty-seven patients with unilateral TLE and 32 controls underwent structural brain MRI. High-dimensional large-deformation mapping provided hippocampal surface and volume estimates for each participant, dividing patients into low versus high hippocampal atrophy groups. A vertex-level generalized linear model compared local shape changes between groups. RESULTS Patients with low-atrophy TLE (MRI negative) had significant local hippocampal shape changes compared to controls, similar to those in the contralateral hippocampus of high-atrophy patients. These changes primarily involved the subicular and hilar/dentate regions, instead of the classically affected CA1 region. Disease duration instead co-varied with lateral hippocampal atrophy, co-localizing with the CA1 subfield. SIGNIFICANCE These findings show that patients with "MRI-negative" TLE have regions of hippocampal atrophy that cluster medially, sparing the lateral regions (CA1) involved in high-atrophy patients. This suggests an overall effect of temporal lobe seizures manifesting as bilateral medial hippocampal atrophy, and a more selective effect of hippocampal seizures leading to disease-proportional CA1 atrophy, potentially reflecting epileptogenesis.
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Affiliation(s)
- Luigi Maccotta
- Department of Neurology, Washington University, St. Louis, Missouri, U.S.A
| | - Emily D Moseley
- Department of Neurology, Washington University, St. Louis, Missouri, U.S.A
| | - Tammie L Benzinger
- Department of Radiology, Washington University, St. Louis, Missouri, U.S.A.,Department of Neurological Surgery, Washington University, St. Louis, Missouri, U.S.A
| | - R Edward Hogan
- Department of Neurology, Washington University, St. Louis, Missouri, U.S.A
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17
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Seo H, Seol MJ, Lee K. Differential expression of hyperpolarization-activated cyclic nucleotide-gated channel subunits during hippocampal development in the mouse. Mol Brain 2015; 8:13. [PMID: 25761792 PMCID: PMC4352274 DOI: 10.1186/s13041-015-0103-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 02/12/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels help control the rhythmic activation of pacemaker neurons during brain development. However, little is known about the timing and cell type specificity of the expression of HCN isoforms during development of the hippocampus. RESULTS Here we examined the developmental expression of the brain-enriched HCN1, HCN2, and HCN4 isoforms of HCN channels in mouse hippocampus from embryonic to postnatal stages. All these isoforms were expressed abundantly in the hippocampus at embryonic day 14.5 and postnatal day 0. Each HCN channel isoform showed subfield-specific expression within the hippocampus from postnatal day 7, and only HCN4 was found in glial cells in the stratum lacunosum moleculare at this developmental stage. At postnatal days 21 and 56, all HCN isoforms were strongly expressed in the stratum lacunosum moleculare and the stratum pyramidale of the Cornu Ammonis (CA), as well as in the hilus of the dentate gyrus, but not in the subgranular zone. Furthermore, the immunolabeling for all these isoforms was colocalized with parvalbumin immunolabeling in interneurons of the CA field and in the dentate gyrus. CONCLUSIONS Our mapping data showing the temporal and spatial changes in the expression of HCN channels suggest that HCN1, HCN2, and HCN4 subunits may have distinct physiological roles in the developing hippocampus.
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Affiliation(s)
- Hyunhyo Seo
- Department of Anatomy, Brain Science & Engineering Institute, Kyungpook National University Graduate School of Medicine, 2-101, Dongin-dong, Jung-gu, Daegu, 700-842, South Korea.
| | - Myoung-Jin Seol
- Department of Anatomy, Brain Science & Engineering Institute, Kyungpook National University Graduate School of Medicine, 2-101, Dongin-dong, Jung-gu, Daegu, 700-842, South Korea.
| | - Kyungmin Lee
- Department of Anatomy, Brain Science & Engineering Institute, Kyungpook National University Graduate School of Medicine, 2-101, Dongin-dong, Jung-gu, Daegu, 700-842, South Korea.
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18
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Besson P, Lopes R, Leclerc X, Derambure P, Tyvaert L. Intra-subject reliability of the high-resolution whole-brain structural connectome. Neuroimage 2014; 102 Pt 2:283-93. [DOI: 10.1016/j.neuroimage.2014.07.064] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 07/24/2014] [Accepted: 07/30/2014] [Indexed: 01/09/2023] Open
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19
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Joo EY, Kim H, Suh S, Hong SB. Hippocampal substructural vulnerability to sleep disturbance and cognitive impairment in patients with chronic primary insomnia: magnetic resonance imaging morphometry. Sleep 2014; 37:1189-98. [PMID: 25061247 DOI: 10.5665/sleep.3836] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
STUDY OBJECTIVES Despite compelling evidence from animal studies indicating hippocampal subfield-specific vulnerability to poor sleep quality and related cognitive impairment, there have been no human magnetic resonance imaging (MRI) studies investigating the relationship between hippocampal subfield volume and sleep disturbance. Our aim was to investigate the pattern of volume changes across hippocampal subfields in patients with primary insomnia relative to controls. DESIGN Pointwise morphometry allowed for volume measurements of hippocampal regions on T1-weighted MRI. SETTING University hospital. PATIENTS Twenty-seven unmedicated patients (age: 51.2 ± 9.6 y) and 30 good sleepers as controls (50.4 ± 7.1 y). INTERVENTIONS N/A. MEASUREMENTS We compared hippocampal subfield volumes between patients and controls and correlated volume with clinical and neuropsychological features in patients. RESULTS Patients exhibited bilateral atrophy across all hippocampal subfields (P < 0.05 corrected). Cornu ammonis (CA) 1 subfield atrophy was associated with worse sleep quality (higher Pittsburgh Sleep Quality Index and higher arousal index of polysomnography) (r < -0.45, P < 0.005). The volume of the combined region, including the dentate gyrus (DG) and CA3-4, negatively correlated with verbal memory, verbal information processing, and verbal fluency in patients (|r| > 0.45, P < 0.05). Hemispheric volume asymmetry of this region (left smaller than right) was associated with impaired verbal domain functions (r = 0.50, P < 0.005). CONCLUSION Hippocampal subfield atrophy in chronic insomnia suggests reduced neurogenesis in the dentate gyrus (DG) and neuronal loss in the cornu ammonis (CA) subfields in conditions of sleep fragmentation and related chronic stress condition. Atrophy in the CA3-4-DG region was associated with impaired cognitive functions in patients. These observations may provide insight into pathophysiological mechanisms that make patients with chronic sleep disturbance vulnerable to cognitive impairment. CITATION Joo EY, Kim H, Suh S, Hong SB. Hippocampal substructural vulnerability to sleep disturbance and cognitive impairment in patients with chronic primary insomnia: magnetic resonance imaging morphometry.
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Affiliation(s)
- Eun Yeon Joo
- Sleep Center, Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Samsung Biomedical Research Institute, Seoul, Korea
| | - Hosung Kim
- Department of Neurology and Brain Imaging Center, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Sooyeon Suh
- Korea University Ansan Hospital, Human Genome Institute, Korea University, Seoul, Korea ; Stanford University, Department of Psychiatry, Redwood City, CA
| | - Seung Bong Hong
- Sleep Center, Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Samsung Biomedical Research Institute, Seoul, Korea
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Hogan RE, Moseley ED, Maccotta L. Hippocampal surface deformation accuracy in T1-weighted volumetric MRI sequences in subjects with epilepsy. J Neuroimaging 2014; 25:452-9. [PMID: 24942549 DOI: 10.1111/jon.12135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 03/07/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE To demonstrate the accuracy across different acquisition and analysis methods, we evaluated the variability in hippocampal volumetric and surface displacement measurements resulting from two different MRI (magnetic resonance imaging) acquisition protocols. METHODS Nine epilepsy patients underwent two independent T1-weighted magnetization prepared spoiled gradient sequences during a single 3T MRI session. Using high-dimension mapping-large deformation (HDM-LD) segmentation, we calculated volumetric estimates and generated a vector-based 3-dimensional surface model of each subject's hippocampi, and evaluated volume and surface changes, the latter using a cluster-based noise estimation model. RESULTS Mean hippocampal volumes and standard deviations for the left hippocampi were 2,750 (826) mm3 and 2,782 (859) mm3 (P = .13), and for the right hippocampi were 2,558 (750) mm3 and 2,547 (692) mm3 (P = .76), respectively for the MPR1 and MPR2 sequences. Average Dice coefficient comparing overlap for segmentations was 86%. There was no significant effect of MRI sequence on volume estimates and no significant hippocampal surface change between sequences. CONCLUSION Statistical comparison of hippocampal volumes and statistically thresholded HDM-LD surfaces in TLE patients showed no differences between the segmentations obtained in the two MRI acquisition sequences. This validates the robustness across MRI sequences of the HDM-LD technique for estimating volume and surface changes in subjects with epilepsy.
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Affiliation(s)
- R Edward Hogan
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
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Besson P, Dinkelacker V, Valabregue R, Thivard L, Leclerc X, Baulac M, Sammler D, Colliot O, Lehéricy S, Samson S, Dupont S. Structural connectivity differences in left and right temporal lobe epilepsy. Neuroimage 2014; 100:135-44. [PMID: 24814212 DOI: 10.1016/j.neuroimage.2014.04.071] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 04/16/2014] [Accepted: 04/28/2014] [Indexed: 12/20/2022] Open
Abstract
Our knowledge on temporal lobe epilepsy (TLE) with hippocampal sclerosis has evolved towards the view that this syndrome affects widespread brain networks. Diffusion weighted imaging studies have shown alterations of large white matter tracts, most notably in left temporal lobe epilepsy, but the degree of altered connections between cortical and subcortical structures remains to be clarified. We performed a whole brain connectome analysis in 39 patients with refractory temporal lobe epilepsy and unilateral hippocampal sclerosis (20 right and 19 left) and 28 healthy subjects. We performed whole-brain probabilistic fiber tracking using MRtrix and segmented 164 cortical and subcortical structures with Freesurfer. Individual structural connectivity graphs based on these 164 nodes were computed by mapping the mean fractional anisotropy (FA) onto each tract. Connectomes were then compared using two complementary methods: permutation tests for pair-wise connections and Network Based Statistics to probe for differences in large network components. Comparison of pair-wise connections revealed a marked reduction of connectivity between left TLE patients and controls, which was strongly lateralized to the ipsilateral temporal lobe. Specifically, infero-lateral cortex and temporal pole were strongly affected, and so was the perisylvian cortex. In contrast, for right TLE, focal connectivity loss was much less pronounced and restricted to bilateral limbic structures and right temporal cortex. Analysis of large network components revealed furthermore that both left and right hippocampal sclerosis affected diffuse global and interhemispheric connectivity. Thus, left temporal lobe epilepsy was associated with a much more pronounced pattern of reduced FA, that included major landmarks of perisylvian language circuitry. These distinct patterns of connectivity associated with unilateral hippocampal sclerosis show how a focal pathology influences global network architecture, and how left or right-sided lesions may have differential and specific impacts on cerebral connectivity.
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Affiliation(s)
- Pierre Besson
- Department of clinical neurophysiology EA 1048, Lille University Hospital, France; In-vivo Imaging Platform, IMPRT, Lille University Hospital, France
| | - Vera Dinkelacker
- Epilepsy Unit, Hôpital de la Pitié-Salpêtrière, APHP, Paris, France; Centre de Neuroimagerie de Recherche (CENIR), Paris, France; Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France.
| | - Romain Valabregue
- Centre de Neuroimagerie de Recherche (CENIR), Paris, France; Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Lionel Thivard
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Xavier Leclerc
- In-vivo Imaging Platform, IMPRT, Lille University Hospital, France
| | - Michel Baulac
- Epilepsy Unit, Hôpital de la Pitié-Salpêtrière, APHP, Paris, France; Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Daniela Sammler
- Centre de Neuroimagerie de Recherche (CENIR), Paris, France; Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Olivier Colliot
- Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France; INRIA, Aramis Team, Centre de Recherche Paris-Rocquencourt, France
| | - Stéphane Lehéricy
- Centre de Neuroimagerie de Recherche (CENIR), Paris, France; Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
| | - Séverine Samson
- Epilepsy Unit, Hôpital de la Pitié-Salpêtrière, APHP, Paris, France; Laboratoire de Neurosciences Fonctionnelles et Pathologies (EA 4559), Université Lille-Nord de France, France
| | - Sophie Dupont
- Epilepsy Unit, Hôpital de la Pitié-Salpêtrière, APHP, Paris, France; Centre de Neuroimagerie de Recherche (CENIR), Paris, France; Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris, France
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