Corpus Callosum Integrity and Neuropsychological Performance After Traumatic Brain Injury: A Diffusion Tensor Imaging Study

Objectives: (1) Detailed analysis of diffusion tensor imaging (DTI) parameters (fractional anisotropy and radial diffusivity) to evaluate white matter integrity in the corpus callosum (CC), and (2) examine correlations between DTI data and performance on multiple measures of cognitive functioning. Participants: Twelve individuals with a history of complicated mild, moderate, or severe traumatic brain injury (TBI) who were an average of 1.7 years postinjury and 12 control participants. Main Measures: Standardized and experimental neuropsychological tests; detailed analysis of DTI parameters. Results: The TBI group demonstrated DTI values suggesting decreased white matter integrity and correlations with severity of injury. Both groups showed correlations between DTI parameters and cognitive measures, with more significant correlations observed for the TBI group. White matter changes in the CC were evident chronically and were related to severity of injury. Conclusions: Diffusion tensor imaging parameters suggesting disruptions in white matter in the CC may be implicated in impaired performance, both in terms of cognitive tasks and reaction time, after TBI.