7T DTI in Mild Chronic Traumatic Brain Injury: Assessment of the Superior Longitudinal Fasciculus and Cingulum Bundle

Introduction: Mild chronic traumatic brain injury (TBI) causes behavioral deficits without changes to standard anatomical MRI. The event of mild TBI causes axonal shearing which disrupts the highly organized bundles of nerve fibers. Diffusion tensor imaging (DTI) is sensitive to water diffusion along or across these fiber bundles. Quantitative parameters of DTI such as fractional anisotropy (FA), apparent diffusion coefficient (ADC), and fiber tractography through the entire corpus callosum and genu have already been analyzed at 7T and show promise in differentiating mild chronic TBI patients and age matched healthy controls [1]. As behavioral deficits in TBI indicate frontal brain injury, it is of significant interest to evaluate other fibers which have been implicated [2]. The objective of this study was to assess the potential of 7T DTI to analyze the superior longitudinal fasciculus (SLF) and the cingulum bundle (CB) in mild chronic TBI patients.