Diffusion tensor imaging and magnetic resonance spectroscopy in traumatic brain injury: a review of recent literature

Concussion is the most common form of traumatic brain injury (TBI), but diagnosis remains controversial because the brain appears quite normal in conventional computed tomography and magnetic resonance imaging (MRI). These conventional tools are not sensitive enough to detect diffuse traumatic axonal injury, and cannot depict aberrations in mild TBIs. Advanced MRI modalities including diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS), make it possible to detect brain injuries in TBI. The purpose of this review is to provide the latest information regarding the visualization and quantification of important abnormalities in TBI and new insights into their clinical significance. Advanced imaging modalities allow the discovery of biomarkers of injury and the detection of changes in brain injury over time. Such tools will likely be used to evaluate treatment efficacy in research. Combining multiple imaging modalities would not only provide greater insight into the underlying physiological changes in TBI, but also improve diagnostic accuracy in predicting outcomes. In this review we present evidence of brain abnormalities in TBI based on investigations using MRI, including DTI and MRS. Our review provides a summary of some of the important studies published from 2002 to 2012 on the topic of MRI findings in head trauma. With the growing realization that even mild head injury can lead to neurocognitive deficits, medical imaging has assumed preeminence for detecting abnormalities associated with TBI. Advanced MRI modalities such as DTI and MRS have an important role in the diagnosis of lesions for TBI patients.