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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    • "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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