Population averaged Coronal MTR maps.

<p>MTR maps at the level of gCC (top row), iCC (middle row), and sCC (bottom row). ΔMTR (p < 0.01) values are overlaid in false color (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0152480#pone.0152480.g005" target="_blank">Fig 5</a> for color bar) in the far right column. Note reduced image quality at Cz Week 6+6 due small number of images included in the average (n = 5) compared to Baseline (n = 24) and Cz Week 6 (n = 14).</p

Longitudinal ROI-average MTR Compared to Healthy Age-Matched Controls.

<p>ROI-average MTR scatter plots for the medial- and lateral-CC ROIs illustrated in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0152480#pone.0152480.g002" target="_blank">Fig 2(a)–2(c)</a>. Values represent population average within an ROI. Dashed lines/hollow markers represent data from healthy age-matched controls (n = 10, 4, 5, for Baseline (age postnatal (P) 49), Week 6 (P91), Week 6+6 (P133), respectively); data from cuprizone treated animals are shown with solid lines/filled markers (n = 14, 14, 5, for Baseline, Week 6, Week 6+6, respectively). Error bars represent mean standard error for each group. The shaded bands illustrate the 95% confidence interval for baseline values (±0.01).</p

ROI Selection on Coronal MR Images.

<p>Colored ROIs used in scatter plots below are overlaid on population averaged baseline MTR images. Medial CC is red, lateral CC (including EC) is colored in green on coronal images. A sagittal view with arrows corresponding to the locations of the slices shown in (a-c), corresponding to genu (gCC), body/isthmus (iCC), and splenium (sCC), respectively, is shown in panel (d).</p

T₂-w MRI Compared to BGII.

<p>T₂-w RARE coronal images and pathologic sections stained with Black Gold II for myelin (insets, scale bar 200μm) from mice fed normal chow (a and c), after 6 weeks on cuprizone chow (b) and 6 weeks after stopping cuprizone chow (d). MRI from age-matched control mice (a and c) show low signal intensity in the corpus callosum and corresponding normal myelin on histology. After 6 weeks of cuprizone exposure (b), the corpus callosum has increased signal intensity (now isointense with cortex) and corresponding decreased staining for myelin on histology. Six weeks after being taken off of cuprizone, MRI shows return of hypointensity in the corpus callosum and corresponding increased staining for myelin on histology (d).</p

BGII stain for myelin in corpus callosum—demyelination as percent area.

<p>BGII stain for myelin in corpus callosum—demyelination as percent area.</p

Black Gold II Stain for Myelin in Caudal and Rostral CC.

<p>BGII stains roughly corresponding to gCC (a-c) and sCC (d-f) ROIs in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0152480#pone.0152480.g002" target="_blank">Fig 2</a>. Age-matched control with normal myelinated lat-CC/EC (a); substantial demyelination in rostral lat-CC/EC (arrows) after 6 weeks Cz (b); lat-CC/EC partially recovered after 6 weeks on regular chow (c). Reduction in myelinated fibers in caudoputamen is observed both at Week 6 and Week 6+6 compared to control. Stark demyelination is evident in the caudal med-CC (e, arrowhead), while lat-CC/EC (arrow) is only mildly demyelinated after 6 weeks cuprizone (e) compared to control (d). Remyelination in lat-CC/EC and med-CC is substantial yet incomplete after 6 weeks recovery (f). Blue arrows indicate demyelination in EC beyond the extents of MRI-visible lat-CC/EC.</p

BGII/MTR Hybrid images.

<p>BGII sections compared to MTR maps in gCC, iCC, and sCC. Hybrid BGII/MTR images demonstrate MTR contrast and corresponding BGII staining at the level of gCC (first row), iCC (second row), and sCC (third row) at Baseline (left), Cz Week 6 (middle.), and Cz Week 6+6 (right). Loss of MTR contrast at Week 6 matches changes in BGII staining, representing demyelination (yellow arrows). The black circle in the cortex above gCC at Cz Week 6 is a coverslip bubble and should be ignored.</p

BGII—MTR linear regression.

<p>BGII—MTR linear regression.</p

Weight Gain and Study Design.

<p>Average weight of animals over the course of the study (error bars represent one standard deviation). Cuprizone diet was administered for 6 weeks (shaded area) beginning 3 weeks after delivery. After one week on cuprizone the treatment group (Cz) exhibited lower weight than healthy controls (HC; *p<0.005); weight gain increased one week after cuprizone was removed from the diet, and two weeks into recovery no difference can be seen between the two groups’ weights.</p

Population Average Orthogonal MTR Parametric Maps.

<p>(a,b) Population average MTR projection along midsagittal CC from Caudal (splenium) to Rostral (genu) at Baseline (blue), Week 6 (red), and Week 6+6 (green). (c) Population-average MTR maps at baseline, Cz Week 6, Cz Week 6+6, and HC Week 12. Note that SNR increases with the number of images averaged, resulting in poorer image quality in Cz Week 6+6 and HC Week 12 images.</p