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Diffusion Kurtosis Imaging of Persistent Developmental Stuttering
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- Author / Creator
- Misaghi, Ehsan
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Stuttering is a developmental speech disorder characterized by prolongations and/or repetitions of speech sounds as well as silent blocks during speech production. It affects about 5% of children and 1% of the general population. Growing evidence shows that white matter connections of the brain show deficiencies in people who stutter. Examples of those connections include the arcuate fasciculus, the frontal aslant tract, the corpus callosum and the corticospinal tract. A widely used method to assess the white matter in vivo is diffusion magnetic resonance imaging. Tractography methods based on Diffusion Tensor Imaging (DTI) are able to isolate the white matter connections of the brain. However, DTI has some limitations. For instance, it is based on the assumption that the diffusion pattern follows a Gaussian distribution, while studies have shown that in specific circumstances, e.g. in complex cell compartments, diffusion can deviate from the Gaussian distribution. Kurtosis metrics are able to quantify this deviation and Diffusion Kurtosis Imaging (DKI) gives us the ability to extract the said metrics. Thus, DKI was used in this study to assess the white matter connections of the brain in a group of adults who stutter and a group of age-, sex-, handedness- and education level-matched controls. Using tractography, I delineated the corpus callosum, arcuate fasciculus, frontal aslant tract and corticospinal tract. The results of this study showed that adults who stutter have higher axial kurtosis in the left frontal aslant tract in comparison to controls and to their right frontal aslant tract. Furthermore, radial kurtosis in the right frontal aslant tract of adults who stutter was negatively correlated with the impact of stuttering on their daily lives. Based on these results, it is suggested that the deficits in the frontal aslant tract are associated with the dysfluency encountered in stuttering.
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- Graduation date
- Spring 2017
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- Type of Item
- Thesis
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- Degree
- Master of Science
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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.