CSF T-Tau/Aβ42 and mean diffusivity.

<p>Higher T-Tau/Aβ42 at baseline was associated with increased mean diffusivity in follow-up scanning in several brain regions, encompassing both gray and white matter. As shown above, this relationship was especially prominent in temporal lobe white matter adjacent to hippocampus, but also encompassing gray and white matter in frontal and parietal lobes, portions of occipital white matter, and small clusters in cerebellum. Results are FDR corrected for multiple comparisons (p<.05) and displayed here with a cluster size threshold of 20 or more voxels. Sections are shown in sagittal view beginning from the left side of the brain to right. Variations in the color map reflect the size of the T-statistic (indexed by the color bar at bottom).</p

T-Tau/Aβ42 Plotted against mean, radial, and axial diffusivity.

<p>Shown here are the results of the voxel-wise analysis, where regions with color overlay are those where higher T-Tau/Aβ42 was associated with higher diffusivity (mean, radial, and axial). In order to illustrate the relationship between T-Tau/Aβ42 and the diffusivity maps, we extracted diffusion values from representative regions of significant correlation in the voxel-wise analysis and plotted them against T-Tau/Aβ42. Shown on the top row are diffusion values extracted from the left temporal lobe (x = −42, y = −34, z = −16) plotted against T-Tau/Aβ42. In the middle row are diffusion values extracted from right posterior cingulum bundle (x = 8, y = −46, z = 16) plotted against T-Tau/Aβ42. In the bottom row are diffusion values extracted from left inferior frontal white matter (x = −22, y = 43, z = −12) plotted against T-Tau/Aβ42. Blue crosshairs overlaid on the brain sections indicate the location of the extracted values. Each point in the scatter represents diffusion values from one participant (n = 43). T-Tau/Aβ42 values were log-transformed and mean, radial, and axial diffusivity values were adjusted for age at time of scan, sex, and treatment (CSF data were collected at baseline in a Simvastatin treatment trial, data from the prevention trial are not shown here).</p

Regions where CSF biomarkers were significantly correlated with FA and MD in the voxel-wise analyses.

<p>MNI: Montreal Neurological Institute; k: cluster size; T-Tau: Total Tau; P-Tau: Phosphorylated Tau; WM: White Matter; L: Left; R: Right.</p><p>× No relationship with any regions at FDR corrected threshold p<.05.</p><p>− No group differences in any region at FDR corrected threshold p<.05.</p

Percent of regional overlap between statistical parametric mapping result maps.

<p>All results maps were the product of a linear correlation analysis, where the CSF measures (T-Tau and T-Tau/Aβ42) were used to predict the diffusion measures (MD, axial and radial diffusivity). T-Tau: Total Tau; MD: Mean Diffusivity; Rad: Radial; Ax: Axial; Diff: Diffusivity.</p>*<p>Result map shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0037720#pone-0037720-g001" target="_blank">Figure 1</a>.</p

Linear correlation among CSF biomarkers and age.

<p>Significant correlation at P<.05 *.</p><p>Significant at p<.001 Ŧ.</p