Relation between cingulum injury and cognition in chronic patients with traumatic brain injury; diffusion tensor tractography study

Abstract

Many diffusion tensor imaging (DTI) studies have reported an association between cingulum injury and cognition in patients with traumatic brain injury (TBI) using DTI parameters. In this study, we attempted to investigate the relation between cingulum injury and cognition in chronic patients with TBI, using the integrity of the cingulum as well as DTI parameters. Thirty five consecutive chronic patients with TBI were recruited. The intelligence quotient (IQ) of the Wechsler Intelligence Scale and Memory Assessment Scale (MAS) was used for assessment of cognition. The patients were classified into three groups, according to continuity to the lower portion of the genu of the corpus callosum: type A-both sides of the cingulum showed intact continuity, type B-either cingulum showed a discontinuation, and, type C-both cingulums showed discontinuation. We measured the fractional anisotropy (FA), apparent diffusion coefficient (ADC), and voxel number of both cingulums. The IQ and MAS scores of type A and B were significantly higher than those of type C, respectively (p < 0.05), however, we did not observe a significant difference between type A and type B (p > 0.05). A positive correlation was observed between the FA value of the cingulum, and IQ and MAS, respectively (IQ r = 0.373, p < 0.05, MAS r = 0.357, p < 0.05), and between the voxel number and MAS (r = 0.500, p < 0.05). By contrast, we observed a negative correlation between the ADC value and IQ (r = -0.353, p < 0.05). In terms of integrity to the basal forebrain and DTI parameters of the injured cingulum, DTI findings showed a close association with whole cognition and memory in chronic patients with TBI.