Diffusion tensor imaging studies on corticospinal tract injury following traumatic brain injury: a review

The corticospinal tract (CST) is the most important neural tract for motor function in the human brain. Therefore, clarification of CST injury would be an important topic in traumatic brain injury (TBI) rehabilitation. In this review, I reviewed diffusion tensor imaging (DTI) studies on CST injuries in terms of etiology and recovery in patients with TBI. Although DTI has several unique advantages for research on CST injury in TBI, only a dozen DTI studies on this topic have been reported: etiology of CST injury (9 studies), recovery of CST injury (3 studies). As for the etiology of CST injury in TBI, the previous studies have demonstrated the usefulness of DTI in diagnosis of CST injury in cases of diffuse axonal injury, transtentorial herniation, cerebral hemorrhage, and cortical contusion; moreover, according to the severity of TBI. The three studies on recovery of CST injury focused on recovery of a CST injured by diffuse axonal injury. In the future, we suggest an increase in the total number of DTI studies on this topic. In particular, research on recovery of CST injury should be encouraged. Moreover, studies of the various recovery mechanisms related to the CST are necessary.