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Magnetic Resonance Imaging of Brain Development in Fetal Alcohol Spectrum Disorders
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- Author / Creator
- Treit, Sarah C
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Prenatal alcohol exposure has detrimental consequences on brain development, resulting in a wide range of physical, cognitive and behaviour deficits termed fetal alcohol spectrum disorders (FASD). Advanced magnetic resonance imaging (MRI) methods have identified numerous abnormalities of brain structure in groups of individuals with FASD compared to groups of healthy typically developing controls, including volume reductions and abnormalities of cortical thickness and white matter microstructure. Although informative, many previous studies have included limited sample sizes or narrow age ranges, precluding investigation of age-related changes or sex-differences in neurological abnormalities in this population. Moreover, few studies have investigated abnormalities with more than one imaging method in the same sample, needed to determine the relative magnitude of observed impairments. This thesis aims to address these limitations by using advanced imaging methods (high resolution T1-weighted and diffusion tensor imaging) to examine white matter microstructure, cortical thickness and brain volumes in a large cross sectional and longitudinal follow up dataset of individuals diagnosed with FASD. Data presented here uncover novel information about the developmental trajectories of children and adolescents with FASD, demonstrating delayed development of both cortical thickness and white matter microstructure but expected changes in brain volume with age. Cross sectional analysis reveals robust reductions of brain volume, smaller but consistent reductions of cortical thickness and few differences in white matter microstructure between groups. Sex differences are identified in the control group, as expected given known sexual dimorphism of brain structure, but appear to be attenuated in the FASD group. Males with FASD are shown to have greater structural brain impairment than females, despite similar performance on cognitive tests. In addition, novel information on correlations between head circumference (a widely used diagnostic measure of neurological impairment in this population) and brain volume are presented, and implications for diagnosis are discussed. Overall this thesis provides independent evidence of altered brain structure in individuals with FASD, and uncovers novel information about sex differences, developmental trajectories, and brain-behaviour relationships that will help advance the development of medical and behavioural interventions for this population.
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- Graduation date
- Fall 2015
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- Type of Item
- Thesis
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- Degree
- Doctor of Philosophy
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- License
- This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.