Cortical thickness measured from MRI in the YAC128 mouse model of Huntington's disease

The Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.
NeuroImage (Impact Factor: 6.36). 07/2008; 41(2):243-51. DOI: 10.1016/j.neuroimage.2008.02.019
Source: PubMed


A recent study found differences in localised regions of the cortex between the YAC128 mouse model of Huntington's Disease (HD) and wild-type mice. There are, however, few tools to automatically examine shape differences in the cortices of mice. This paper describes an algorithm for automatically measuring cortical thickness across the entire cortex from MRI of fixed mouse brain specimens. An analysis of the variance of the method showed that, on average, a 50 microm (0.05 mm) localised difference in cortical thickness can be measured using MR scans. Applying these methods to 8-month-old YAC128 mouse model mice representing an early stage of HD, we found an increase in cortical thickness in the sensorimotor cortex, and also revealed regions wherein decreasing striatal volume correlated with increasing cortical thickness, indicating a potential compensatory response.

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Available from: Mark Henkelman, Oct 05, 2015
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    • "For neurodegenerative diseases, the progression of pathology might vary between two hemispheres [20]. Furthermore, for studies interested in further estimating the cortical thickness from the structural parcellation result, hemisphere separation can also help to identify and segment the intra-hemispheric cortical surface area [42], [43]. It is thus preferable to separate the structural labels of the original atlas into left and right hemispheres. "
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    ABSTRACT: Multi-atlas segmentation propagation has evolved quickly in recent years, becoming a state-of-the-art methodology for automatic parcellation of structural images. However, few studies have applied these methods to preclinical research. In this study, we present a fully automatic framework for mouse brain MRI structural parcellation using multi-atlas segmentation propagation. The framework adopts the similarity and truth estimation for propagated segmentations (STEPS) algorithm, which utilises a locally normalised cross correlation similarity metric for atlas selection and an extended simultaneous truth and performance level estimation (STAPLE) framework for multi-label fusion. The segmentation accuracy of the multi-atlas framework was evaluated using publicly available mouse brain atlas databases with pre-segmented manually labelled anatomical structures as the gold standard, and optimised parameters were obtained for the STEPS algorithm in the label fusion to achieve the best segmentation accuracy. We showed that our multi-atlas framework resulted in significantly higher segmentation accuracy compared to single-atlas based segmentation, as well as to the original STAPLE framework.
    PLoS ONE 01/2014; 9(1):e86576. DOI:10.1371/journal.pone.0086576 · 3.23 Impact Factor
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    • "The final deformation fields that aligned each individual scan to the average were then analyzed using the Jacobian determinant to compute local volume change (Lerch et al., 2011b) for each mouse. Cortical thickness was also measured using a Laplacian thickness algorithm (Lerch et al., 2008). In addition to the voxel-wise analyses, an anatomical atlas comprised of 62 defined regions (Dorr et al., 2008) was used to perform automated template-based segmentation of regional volumes such that the same labeled template was applied to each scan (Collins et al., 1995). "
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    Clinical neuroimaging 09/2013; 3:290-300. DOI:10.1016/j.nicl.2013.08.017 · 2.53 Impact Factor
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    • "In order to examine X chromosome influences on brain development in a way that attenuates the potentially confounding variables above, we used high resolution (~30 μm 3 ) ex vivo neuroimaging (Lerch et al., 2008) to conduct a spatially fine-grained whole-brain anatomical survey in X-monosomic mice (XO) alongside their XX and XY littermates. Unlike humans with TS, the murine X-monosomy model we studied is necessarily free of karyotypic mosaicism and allows X chromosome parent-of-origin to be pre-specified (Davies et al., 2005). "
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