Figure 1.
(a) The putamen is segmented from T1-weighted images and a conformal grid is built on the surface. Here examples are shown for 2 different subjects (b) Examples of features selected in the image for the two subjects in (a) (c) From left to right: Intensity map on the surface of one of the subjects in (a). Forward map g(x) for the conformal grid fluid registration to a common template. Backward map h(x) from the template to image 1. Intensity map on the surface of the template. (d). Surface mTBM is applied to analyze morphometric changes. Map displays uncorrected p-values on the surface of the putamen from the mTBM analysis.
Figure 2.
While the caudate head is part of the striatum, we chose not to include this structure because of the poor tissue contrast in the anterior limb of the internal capsule in the neonates, which prevented us from obtaining reliable manual contours in this region in neonates. Additionally, our hypothesis testing for this paper included the ventral striatum, which does not contain the caudate head. Note also that the globes palladius, while not part of the putamen, was still included in our segmentation. It is extremely difficult to accurately segment the globus pallidus from the putamen in neonates due to the lack of tissue contrast on volumetric T1 images. However, since our hypothesis is related to the ventral striatal surface, it is not affected by the inclusion of the globus palladius within our putamen contour.
Figure 3.
Top panel: P-values for the comparison of two groups, for 4 different statistics. The meaning of the different colors is shown in the colorbar.
Figure 4.
False Discovery Rate Analysis.
This plot shows the CDFs of p-values vs. p-values. Height above the x = y line indicate how powerful a statistic is, while the point at which the data crosses the y = 20× line, if it exists, represents the threshold at which at most 5% of false positives are expected (see section on Multivariate Statistical Analysis). Both mTBM and the combined measure cross the x = 20 y line but the other measures fail to do so.
Figure 5.
Comparison of Fluid and constrained harmonic registrations.
Top panel: P-values for the comparison of with the two registration methods. Bottom panel: P-values for the comparison of
with the two methods. The left column represents the fluid registration, while the right one is for the constrained harmonic mapping. The meaning of the different colors is shown in the colorbar.