Jeffrey Ware MD, Presenter: Nothing to Disclose

Rosette Biester PhD, Abstract Co-Author: Nothing to Disclose

Elizabeth Whipple MS, Abstract Co-Author: Nothing to Disclose

Keith Robinson MD, Abstract Co-Author: Nothing to Disclose

Richard Ross MD, PhD, Abstract Co-Author: Nothing to Disclose

Paolo Nucifora MD, PhD, Abstract Co-Author: Nothing to Disclose

Mild traumatic brain injury (m-TBI) is an increasingly-recognized clinical problem, particularly in military populations which have seen a dramatic rise in the incidence of m-TBI over the past two decades. TBI has therefore become known as the "signature injury" of recent miltary operations, and it is associated with poor neuropsychiatric outcomes. Clinical evaluation of veterans with m-TBI remains challenging due to difficulties in establishing the diagnosis and selecting appropriate therapy. Reliable biomarkers are sought to improve not only the sensitivity and specificity of m-TBI diagnosis, but also accuracy in predicting clinical outcome and ultimately evaluating therapeutic efficacy.

We performed a retrospective cohort study of veterans of Operation Enduring Freedom and Operation Iraqi Freedom who were evaluated within a single VA hospital system from 2008-2013, screened positive for m-TBI, and were referred for brain MRI including diffusion tensor imaging and a high resolution T1-weighted sequence. Conventional MRI sequences were regarded as normal at clinical interpretation. Additional sequences were used for derivation of diffusion metrics, brain morphometry, and structural connectivity. Veterans underwent baseline clinical and neuropsychological evaluation. Clinical data were collected over a follow-up period of up to 6 years. Imaging metrics were analyzed in group-wise fashion, in addition to regression with baseline and follow-up clinical data.

Significant correlations between baseline imaging metrics and both short-term and long-term clinical outcomes were identified. At the time of imaging, fractional anisotropy in left frontal lobe white matter was positively correlated with percentile performance on the Trail-Making Test, a measure of executive function (p < 0.05). Furthermore, fractional anisotropy was significantly reduced in multiple brain regions in m-TBI veterans who were unemployed at the end of the follow up period compared to those able to obtain employment (p < 0.05).

Metrics derived from baseline neuroimaging are correlated with neurocognitive function and associated with long term employment status.  

Our study suggests that neuroimaging metrics can predict short-term as well as long-term clinical outcomes, building upon existing evidence for imaging biomarkers of m-TBI

Ware, J, Biester, R, Whipple, E, Robinson, K, Ross, R, Nucifora, P, Association of Baseline Neuroimaging with Short-term and Long-term Clinical Outcomes in Combat-related Traumatic Brain Injury.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14000587.html