Anisotropy and Diffusivity Changes in Corpus Callosal Subregions in Chronic Pediatric Traumatic Brain Injury
Kramer L, Hasan K, Sankar A, Bachevalier J, Fletcher J, Ewing-Cobbs L, Prasad M
Volume, fractional anisotropy (FA) and transverse diffusivity of segmented corpus callosum (CC) was measured in chronic traumatically brain injured children (TBI) and controls utilizing diffusion tensor and conventional imaging techniques. We found that CC volumes were globally reduced compared to controls. FA and transverse diffusivity varied across the specific callosal regions in both groups reflecting histological differences of each region. Transverse diffusivity demonstrated the most significant differences between groups, particularly in the genu, posterior body and isthmus. Transverse diffusivity is an indicator of the integrity of myelin and may provide a more precise and sensitive measure of chronic TBI.