Structural brain abnormalities in the common epilepsies assessed in a worldwide ENIGMA study
Citation:
Whelan, C.D. and Altmann, A. and Botia, J.A. and Jahanshad, N. and Hibar, D.P. and Absil, J. and Alhusaini, S. and Alvim, M.K.M. and Auvinen, P. and Bartolini, E. and Bergo, F.P.G. and Bernardes, T. and Blackmon, K. and Braga, B. and Caligiuri, M.E. and Calvo, A. and Carr, S.J. and Chen, J. and Chen, S. and Cherubini, A. and David, P. and Domin, M. and Foley, S. and Franca, W. and Haaker, G. and Isaev, D. and Keller, S.S. and Kotikalapudi, R. and Kowalczyk, M.A. and Kuzniecky, R. and Langner, S. and Lenge, M. and Leyden, K.M. and Liu, M. and Loi, R.Q. and Martin, P. and Mascalchi, M. and Morita, M.E. and Pariente, J.C. and Rodriguez-Cruces, R. and Rummel, C. and Saavalainen, T. and Semmelroch, M.K. and Severino, M. and Thomas, R.H. and Tondelli, M. and Tortora, D. and Vaudano, A.E. and Vivash, L. and Von Podewils, F. and Wagner, J. and Weber, B. and Yao, Y. and Yasuda, C.L. and Zhang, G. and Bargallo, N. and Bender, B. and Bernasconi, N. and Bernasconi, A. and Bernhardt, B.C. and Blumcke, I. and Carlson, C. and Cavalleri, G.L. and Cendes, F. and Concha, L. and Delanty, N. and Depondt, C. and Devinsky, O. and Doherty, C.P. and Focke, N.K. and Gambardella, A. and Guerrini, R. and Hamandi, K. and Jackson, G.D. and Kalviainen, R. and Kochunov, P. and Kwan, P. and Labate, A. and McDonald, C.R. and Meletti, S. and O'Brien, T.J. and Ourselin, S. and Richardson, M.P. and Striano, P. and Thesen, T. and Wiest, R. and Zhang, J. and Vezzani, A. and Ryten, M. and Thompson, P.M. and Sisodiya, S.M., Structural brain abnormalities in the common epilepsies assessed in a worldwide ENIGMA study, Brain, 2018, 141, 2, 391-408Download Item:
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.
Author's Homepage:
http://people.tcd.ie/cdohert
Author: Doherty, Colin
Publisher:
Oxford University PressType of material:
Journal ArticleSeries/Report no:
Brain;141;
2;
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Full text availableKeywords:
Epilepsy, MRI, Thalamus, Precentral gyrusDOI:
http://dx.doi.org/10.1093/brain/awx341Metadata
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