Figure 1.
Representative T2-weighted images (upper row) from a subject imaged over the course of the first two years of life along with the segmented left and right ventricles (lower row) are shown.
Figure 2.
The number of subjects imaged and the number of right and left ventricles available for analysis at each age point is shown in Fig. 2A.
The labels of x-axis in (A) indicate the age range when the subjects were scanned. In contrast, B shows the number of subjects who underwent different numbers of imaging sessions. The labels of x-axis in (B) indicate the number of time that subjects were imaged.
Figure 3.
Distance differences in millimeters (from center to center) of the 10 predefined landmarks between manually and SPHARM-defined correspondences with age for each subject (A).
The error bars in A represent the standard deviations of the distance differences across the 10 predefined landmarks. In contrast, B shows the distance differences of each landmarks for the three subjects, respectively. The error bars here represent the standard deviations across age. The points 1–6 in x-axis were located in the horn while the points 7–10 were located in the body of LVs.
Figure 4.
The total intracranial volume (ICV) and the left and right ventricular volumes with age are shown in A and B, respectively.
The red and blue filled circles in B represent the left and right ventricles, respectively.
Figure 5.
Qualitative comparisons of the shape changes of the right and left lateral ventricles between two contiguous imaging time points are shown.
The correspondence between the color scheme and the age is provided at the bottom of the figure. The opacity of the color is adjusted based on the size of the ventricle such that a high opacity is used for the larger ventricle of the two time points whereas the smaller ventricle is shown using a solid color. Since the volumes of both the left and right ventricles increase in year 1, solid color is used for the older time point and a color with a high opacity is used for the younger time point whereas this scheme is reversed for the comparisons in year 2 where the LV volumes are reduced with age.
Figure 6.
Mean length, radius, and area of the left (a–c and g–i) and right (d–f and j–l) LVs are shown.
The x-axis indicates the anatomical location along the long axis of LV, with point 1 representing the anterior and point 99 the posterior tips. Fig. 6a–f show the raw morphological parameters of the entire LV. The Pij is the p-value comparing between two contiguous time points for a given morphological parameter, where i and j represent the imaging time points and i≠j. Fig. 6g–l provide the differences of mean length, radius, and area between two adjacent time points. Colors indicate different p-values with red (<0.01), orange (0.01<p-value<0.02), yellow (0.02<p-value <0.03), green (0.03<p-value<0.04), blue (0.04<p-value<0.05), and light purple (p-value>0.05), respectively.
Figure 7.
The major growth direction and growth rate of the left LV are shown.
The long axis of the ellipsoids shows the main growth direction, while the length and color demonstrate the growth rate from the first and last imaging time points. The color-bar represents the magnitude of the growth rate.
Figure 8.
The effects of age and gender on shape growth of the ventricles.
(A) The effects of age on the shape growth of the left and right ventricles are shown, respectively. The upper row shows the effects without considering the direction of growth while the age effects on the growth of ventricle along the left-right (X), anterior-posterior (Y), and superior-inferior (Z) directions are shown in the bottom row, respectively. The (–log10(p-value)) corrected for multiple comparison using FDR is overlaid on the ventricles and the color bar represents the –log10(p-value). (B) The effects of gender on the shape growth of the left and right ventricles are shown, respectively. The organization of Fig. 8B is identical to that shown in A.
Figure 9.
The effects of age on the shape differences between the left and right ventricles with age are shown.
The upper row shows the effects without considering the direction of growth while the age effects on the growth of ventricle along the left-right (X), anterior-posterior (Y), and superior-inferior (Z) directions are shown in the bottom row, respectively. The –log10(p-value) corrected for multiple comparison using FDR is overlaid on the ventricles and the color bar represents the –log10(p-value).