Figure 4.

Exploratory evaluation of longitudinal FA and volumetric abnormalities in blast-exposed controls and concussive non-blast TBI compared with non-blast control. Comparison of the number of abnormal FA regions by time point identified only a significant difference at the 1-year follow-up for blast-exposed controls (A) and no differences at any time point for non-blast TBI (B) when compared with non-blast control. There were also no significant differences in the number of abnormal volumetric regions at any time point for either the blast-exposed control (C) or non-blast TBI (D) compared with non-blast controls. P-values reported are adjusted for age, education, gender and scanner at each time point. Subsequent head injury exposure was also collected at the 5-year evaluation and included with the other covariates for Scan 3 statistical adjustment to determine significance. Asterisk indicates P-values that remained significant after Benjamini–Hochberg correction for multiple comparisons.