Example 9 week WT mouse images illustrating processing steps for volumetry analysis.

<p>Orthogonal views of the example T2-weighted in vivo dataset are shown in panel <i>a</i>. The images after semi-automated segmentation to remove signal from non-brain material are shown in panel <i>b</i>. The bias field estimate due to surface coil sensitivity inhomogeneity obtained from N4ITK software is shown in panel <i>c</i>. Panel <i>d</i> is the processed 3D dataset ready for image registration and analysis.</p

Change in the volume of mouse brain regions with age.

<p>Percent change in whole brain and brain region volumes between 3 and 9 months of age for WT (blue) and <i>Npc1</i>^-/- (red) mice. Errors bars indicate the standard deviation of the percent change. Significant effects of genotype (*) and age (*) and significant interaction between age and genotype (*) were determined from a two-way ANOVA and p<0.05 after Holm-Bonferroni correction.</p

Example anatomical MRI images of mice at early and late timepoints.

<p>Example high resolution T2-weighted in vivo images of <i>Npc1</i>^-/- (a-c, g-i) and WT (d-f, j-l) mice at 3 weeks (a-f) and 9 weeks (g-l) of age. At three weeks of age there are only slight differences between in the brains of <i>Npc1</i>^-/- and WT mice, but can be seen in the white matter regions of the brain. These differences become more pronounced at 9 weeks of age. The arrow in panel j points to the region of the corpus callosum and external capsule in a WT mouse, which demonstrates a dark band of intensity compared to the surrounding gray matter. This is reversed in the <i>Npc1</i>^-/- mouse. The cerebellum is circled in panel <i>k</i>, which is visibly reduced in size in the <i>Npc1</i>^-/- mouse at 9 weeks. The arrow in panel <i>l</i> indicates the bright signal of the CSF in the lateral ventricles, which are increased in size in the <i>Npc1</i>^-/- mouse at 9 weeks.</p

Brain region volume^*, effects and interactions in 3 and 9 week old Npc1^-/- and control mice.

<p>Brain region volume^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0178179#t001fn001" target="_blank">*</a>}, effects and interactions in 3 and 9 week old Npc1^-/- and control mice.</p