Intra- and inter-hemispheric structural connectome in agenesis of the corpus callosum

Minghui Shi; Lorena G A Freitas; Megan M Spencer-Smith; Valeria Kebets; Vicki Anderson; Alissandra McIlroy; Amanda G Wood; Richard J Leventer; Dimitri Van De Ville; Vanessa Siffredi

doi:10.1016/j.nicl.2021.102709

Intra- and inter-hemispheric structural connectome in agenesis of the corpus callosum

Neuroimage Clin. 2021:31:102709. doi: 10.1016/j.nicl.2021.102709. Epub 2021 Jun 5.

Affiliations

¹ Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Switzerland; Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland.
² Brain and Mind Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Melbourne, Australia.
³ Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland; Department of Electrical and Computer Engineering, Centre for Sleep and Cognition, Clinical Imaging Research Centre, N.1 Institute for Health, National University of Singapore, Singapore.
⁴ Neuroscience Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia; Brain and Mind Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia; School of Psychological Sciences, University of Melbourne, Melbourne, Australia; Department of Psychology, Royal Children's Hospital, Melbourne, Australia.
⁵ Brain and Mind Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia.
⁶ Brain and Mind Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia; School of Life and Health Sciences Aston Neuroscience Institute, Aston University, Birmingham B4 7ET, UK; School of Psychology, Faculty of Health, Melbourne Burwood Campus, Deakin University, Geelong, Victoria, Australia.
⁷ Department of Paediatrics, University of Melbourne, Melbourne, Australia; Department of Neurology, Royal Children's Hospital, Melbourne, Australia; Neuroscience Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia.
⁸ Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Switzerland; Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland; Brain and Mind Research, Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia; Division of Development and Growth, Department of Paediatrics, Faculty of Medicine, University of Geneva, Switzerland. Electronic address: vanessa.siffredi@unige.ch.

Abstract

Agenesis of the corpus callosum (AgCC) is a congenital brain malformation characterized by the complete or partial failure to develop the corpus callosum. Despite missing the largest white matter bundle connecting the left and right hemispheres of the brain, studies have shown preserved inter-hemispheric communication in individuals with AgCC. It is likely that plasticity provides mechanisms for the brain to adjust in the context of AgCC, as the malformation disrupts programmed developmental brain processes very early on. A proposed candidate for neuroplastic response in individuals with AgCC is strengthening of intra-hemispheric structural connections. In the present study, we explore this hypothesis using a graph-based approach of the structural connectome, which enables intra- and inter-hemispheric analyses at multiple resolutions and quantification of structural characteristics through graph metrics. Structural graph metrics of 19 children with AgCC (13 with complete, 6 with partial AgCC) were compared to those of 29 typically developing controls (TDC). Associations between structural graph metrics and a wide range of neurobehavioral outcomes were examined using a multivariate data-driven approach (Partial Least Squares Correlation, PLSC). Our results provide new evidence suggesting structural strengthening of intra-hemispheric pathways as a neuroplastic response in the acallosal brain, and highlight regional variability in structural connectivity in children with AgCC compared to TDC. There was little evidence that structural graph properties in children with AgCC were associated with neurobehavioral outcomes. To our knowledge, this is the first report leveraging graph theory tools to explicitly characterize whole-brain intra- and inter-hemispheric structural connectivity in AgCC, opening avenues for future research on neuroplastic responses in AgCC.

Keywords: Agenesis of the corpus callosum; Brain plasticity; Graph metrics; Structural connectome.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Agenesis of Corpus Callosum / diagnostic imaging
Brain
Child
Connectome*
Corpus Callosum / diagnostic imaging
Humans
Neuronal Plasticity