Room 150 AG

10:30 - 12:30

Moderators:

Petra S. Hüppi, Duan Xu

Ali Gholipour¹, Catherine Limperopoulos², Cedric Clouchoux², Alireza Akhondi-Asl¹, Judy A. Estroff¹, and Simon K. Warfield^1
1Department of Radiology, Boston Children's Hospital and Harvard Medical School, Boston, MA, United States, ²Children's National Medical Center, Washington, DC, United States

The MRI study of the developing brain is challenged by the difficulty of scanning neonates and fetuses, and the rapid changes in the brain anatomy. The recent advances in volumetric fetal brain MRI have enabled the construction of spatiotemporal templates. The anatomic variations are encoded by probability maps in probabilistic templates, but are encoded in the deformation fields in deformable templates. While the recent work has focused on probabilistic spatiotemporal template construction to characterize normal fetal brain development, this work has focused on deformable spatiotemporal template construction; and suggests kernel regression integrated with symmetric normalization for diffeomorphic spatiotempral template construction.

Xianjun Li^1,2, Jie Gao¹, Yumiao Zhang¹, Xue Luo^1,2, Jianghong Han¹, Gang Niu¹, Mingxi Wan², Ed X. Wu³, and Jian Yang^1,2
1Department of Radiology, The First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi, China, ²Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, China, ³Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong, Hong Kong SAR, China

The purpose of this study was to investigate the white matter changes of diffusion parameters derived from white matter model of diffusion kurtosis imaging (DKI) in preterm and term neonates using tract-based spatial statistics (TBSS) analysis. In this study, 38 neonates with postmenstrual ages of 33 to 42 weeks were studied, including 19 preterm neonates and 19 term neonates. The results showed that significant increase of intra-axonal diffusivity without significant changes of axial diffusivity in extra-axonal space and radial diffusivity in extra-axonal space in genu of corpus callosum and body of corpus callosum, reflecting the increase of the alignment, caliber and number of axons. In posterior limb of internal capsule and splenium of corpus callosum, increased diffusion kurtosis or restriction were accompanied by the reduced diffusivity in radial direction. Such diffusivity and kurtosis analysis can be valuable to our understanding the white matter changes in intra-axon and extra-axon space during early development.

Nicolas Kunz¹, Hui Zhang², Yaniv Assaf³, François Lazeyras⁴, Daniel Alexander², and Petra Susan Hüppi^1,5
1Pediatrics, University of Geneva, Geneva, Switzerland, ²Computer Science, University College London, London, United Kingdom, ³Neurobiology, Tel Aviv University, Tel Aviv, Israel, ⁴Radiology-CIBM, Geneva University Hospitals, Geneva, Switzerland, ⁵Department of Neurology, Children’s Hospital, Geneva, Switzerland

Diffusion tensor imaging (DTI), may be the only feasible technique to study micorstructural changes occurring during the brain development. The main aims of this study was to design a complete new pipeline to perform micro-structural diffusion analysis in neonatal brain and to compare DTI to CHARMED and NODDI, which provides new microstructural metrics such as the intra-axonal volume fraction (VFia). High quality subject template was generated using DTI-TK tensor registration tools, which allows the accurate definitions of 13 ROIs. FA and VFia were able to depict fine mircostructural differences in early maturation fiber tracts.

Jacques-Donald Tournier^1,2, Serena J. Counsell³, David A. Raffelt¹, Nora Tusor⁴, Phumza Nongena⁴, A. David Edwards³, Joseph V. Hajnal³, and Alan Connelly^1,2
1Advanced MRI development, The Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia, ²Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia, ³Centre for the Developing Brain, King's College London, London, London, United Kingdom,⁴Department of Medicine (Paediatrics), Imperial College London, London, London, United Kingdom

Preterm birth is associated with poor neurodevelopmental performance, and diffuse white matter injury is frequently observed. In this study, we investigate the effect of gestational age at birth on a new direction-specific measure, the apparent fibre density (AFD), using a high b-value, high angular resolution diffusion imaging (HARDI) acquisition. 31 neonates were scanned at term, and the AFD correlated with gestational age, regressing out post-menstrual age at scan. Significant correlations were observed bilaterally in most major white matter tracts, consistent with previous DTI findings. AFD allows the identification of direction-specific changes, making interpretation of results more straightforward than using scalar measures.

Kerstin Pannek¹, Xanthy Hatzigeorgiou², Paul Colditz³, and Stephen Rose^4
1The University of Queensland, Brisbane, Queensland, Australia, ²Novita Children's Services, Adelaide, Australia, ³The University of Queensland, Brisbane, Australia, ⁴The Australian E-Health Research Centre, CSIRO, Brisbane, Australia

Preterm birth is associated with a high prevalence of adverse neurodevelopmental outcome. We used diffusion MRI and T2 relaxometry to assess alterations in cortico-cortical connectivity in the preterm brain at term equivalent age. Cortical networks associated with affected connections mainly involved left frontal and motor cortical areas. Identified cortical regions are associated with higher cognitive function, working memory, language production, verbal comprehension, executive function and motor function, deficits in which are often observed in children and adults born preterm.

Katyucia de Macedo Rodrigues^1,2, Emma Ben-Avi², Myong-Sun Choe³, Marie Drottar³, Patricia Ellen Grant^2,4, and Lilla Zöllei^2,3
1Radiology, Boston Children's Hospital, Boston, MA, United States, ²Radiology, A.A. Martinos Center for Biomedical Imaging/Massachusetts General Hospital, Charlestown, MA, United States, ³Newborn Medicine, Boston Children's Hospital, Boston, MA, United States, ⁴Newborn Medicine, Radiology, Boston Children's Hospital, Boston, MA, United States

The importance of the thalamus on motor, somatosensory and cognitive functions is well recognized. The study of the thalamic structure with its nuclear subdivisions in the pediatric population could shed a light on thalamic development and changes secondary to pathological states. In this study, we demonstrate the feasibility of thalamic parcellation in clusters that have an anatomical and functional correspondence to known thalamic nuclei in a neonatal population. This parcellation is derived from thalamic connections to predefined neocortical targets observed using probabilistic diffusion tractography.

Tina Jeon¹, Virendra Mishra¹, and Hao Huang^1
1Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, United States

Cortical thinning during brain development is due to complicated cellular and molecular processes including synaptic pruning, apoptosis and cell shrinkage during development. In parallel, association and commissural white matter tracts project from a group of selected and preserved neurons and connect certain cortical regions. These parallel processes are essential for the formation of the brain circuits which enable certain brain functions, especially those related to mental disorders. In this study, we investigated the relationship of the change of fractional anisotropy of these axons and change of the corresponding cortical thickness with DTI and T1-weighted images from 39 normal children.

Jonathan O'Muircheartaigh^1,2, Douglas C. Dean III¹, Holly Dirks¹, Nicole Waskiewicz¹, Katie Lehman¹, Michelle Han¹, Lindsay Walker¹, Beth A. Jerskey¹, and Sean C. L. Deoni^1
1Engineering, Brown University, Providence, Rhode Island, United States, ²Neuroimaging, King's College London, London, London, United Kingdom

The trajectory of myelination in the developing brain is coupled with progressive optimisation of cognitively relevant brain networks. Here we use a multivariate technique, independent component analysis, to parcellate quantitative myelin maps (mcDESPOT) from 200 children between 3 months and 5 years, into clusters with consistent developmental trajectories. We demonstrate distributed, functionally relevant, systems that myelinate concurrently.

Man Wong¹, Andrew Melbourne², Manuel Jorge Cardoso², Gemma Northam¹, Sebastien Ourselin², and Torsten Baldeweg^1
1Institute for Childs Health, University College London, London, United Kingdom, ²Centre for Medical Image Computing, University College London, London, United Kingdom

Differences are observed between the brain volumes and cortical folding pattern of preterm-born and control groups at adolescence.

Massimo Filippi¹, Paola Valsasina¹, Paolo Misci¹, Andrea Falini², Giancarlo Comi³, and Maria A. Rocca^1
1Neuroimaging Research Unit, Institute of Experimental Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, MI, Italy, ²Department of Neuroradiology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, MI, Italy, ³Department of Neurology, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, MI, Italy

In this study, we explored gender- and age-related effects on resting state (RS) functional connectivity within and among networks with potential functional relevance. RS data were acquired from 285 healthy controls (148 men and 137 women, range=8-79 years). Abnormalities of connectivity within and among networks, as detected by independent component analysis and functional network connectivity, were found in almost all RS networks; however, age and gender effects were variable across networks. Our results might contribute to the understanding of gender-related differences in the pathobiology of aging.