DTI May Predict One-Year Outcome in Mild Traumatic Brain Injury

Diffusion tensor imaging (DTI) can detect abnormalities that significantly relate to long-term outcomes in mild traumatic brain injury (TBI), according to a study published in the American Journal of Neuroradiology.

Researchers from New York performed a prospective study to identify early DTI biomarkers in mild TBI that may significantly relate to one-year outcomes.

Thirty-nine subjects with TBI and 40 controls underwent DTI, those with TBI were within 16 days of the injury. The researchers assessed subject-specific regions of abnormally high and low fractional anisotropy and calculated mean fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity across all white matter voxels brain-wide and each of several white matter regions. Twenty-six subjects with TBI returned for one-year follow-up, which included assessment of cognitive performance and symptom burden.

Comparing the images from the subjects with TBI and controls, the researchers saw significant associations of brain-wide DTI measures and outcomes that included the following: mean radial diffusivity and mean diffusivity with memory; and mean fractional anisotropy, radial diffusivity, and mean diffusivity with health-related quality of life.[[{"type":"media","view_mode":"media_crop","fid":"49489","attributes":{"alt":"Traumatic brain injury","class":"media-image media-image-right","id":"media_crop_3032878128126","media_crop_h":"0","media_crop_image_style":"-1","media_crop_instance":"5987","media_crop_rotate":"0","media_crop_scale_h":"0","media_crop_scale_w":"0","media_crop_w":"0","media_crop_x":"0","media_crop_y":"0","style":"height: 170px; width: 170px; border-width: 0px; border-style: solid; margin: 1px; float: right;","title":"©Chris Bjornberg/Shutterstock.com","typeof":"foaf:Image"}}]]

There were also significant differences in outcomes at one year between subjects with and without abnormally high fractional anisotropy for left frontal lobe and left temporal lobe with attention, left and right cerebelli with somatic postconcussion symptoms, and right thalamus with emotional postconcussion symptoms.

The researchers concluded that individualized assessment of DTI abnormalities significantly related to long-term outcomes in mild TBI, with abnormally high fractional anisotropy significantly associated with better outcomes. This could represent an imaging correlate of postinjury compensatory processes.