A Review of the Effectiveness of Neuroimaging Modalities for the Detection of Traumatic Brain Injury

Abstract

The incidence of traumatic brain injury (TBI) in the United States was 3.5 million cases in 2009, according to the Centers for Disease Control and Prevention. It is a contributing factor in 30.5% of injury-related deaths among civilians. Additionally, since 2000, more than 260,000 service members were diagnosed with TBI, with the vast majority classified as mild or concussive (76%). The objective assessment of TBI via imaging is a critical research gap, both in the military and civilian communities. In 2011, the Department of Defense (DoD) prepared a congressional report summarizing the effectiveness of seven neuroimaging modalities (computed tomography [CT], magnetic resonance imaging [MRI], transcranial Doppler [TCD], positron emission tomography, single photon emission computed tomography, electrophysiologic techniques [magnetoencephalography and electroencephalography], and functional near-infrared spectroscopy) to assess the spectrum of TBI from concussion to coma. For this report, neuroimaging experts identified the most relevant peer-reviewed publications and assessed the quality of the literature for each of these imaging technique in the clinical and research settings. Although CT, MRI, and TCD were determined to be the most useful modalities in the clinical setting, no single imaging modality proved sufficient for all patients due to the heterogeneity of TBI. All imaging modalities reviewed demonstrated the potential to emerge as part of future clinical care. This paper describes and updates the results of the DoD report and also expands on the use of angiography in patients with TBI.

A fixel‐based analysis of micro‐ and macro‐structural changes to white matter following adult traumatic brain injury

“…DTI has previously been used to examine WM changes following TBI and has identified many regions where there appears to be damage (for reviews, see Amyot et al, ; Niogi & Mukherjee, ; Shenton et al, ; Wallace et al, ). However, DTI is limited by the fact that the measures obtained from it (FA, MD) are averaged across all of the fibre tracts that are contained within a voxel, making interpretation problematic when more than one fibre tract is present (Mori & Tournier, ).…”

Sleep, Sleep Disorders, and Mild Traumatic Brain Injury. What We Know and What We Need to Know: Findings from a National Working Group

“…In patients with typical mTBI, standard acute structural imaging studies such as head computed tomography scans do not show hemorrhage or other overt structural abnormalities. Specialized imaging modalities with magnetic resonance imaging, such as susceptibility weighted imaging, may show evidence of old hemosiderin as a proxy for diffuse axonal injury, and newer imaging techniques such as diffusion tensor imaging and functional magnetic resonance imaging hold promise for future clinical use [11]. However, an absence of findings, even on highly specialized imaging modalities, does not rule out mTBI, as the neurological sequelae of mTBI are believed to be caused by a transient disruption of brain function, including impairment of synaptic transmission, alterations in glucose metabolism, changes in cerebral blood flow, and impaired axonal function [12].…”

Using functional and molecular MRI techniques to detect neuroinflammation and neuroprotection after traumatic brain injury

“…It is a complex injury that results in primary injury and secondary injury cascades. Variable outcomes of patients after TBI and the multiple definitions of TBI make interpreting results across research studies challenging (Amyot et al, 2015). Currently, no drug is effective for treatment of TBI, and clinical trials of neuroprotective drugs have not shown clear benefit in reducing or preventing secondary brain damage (McConeghy et al, 2012).…”

“…MRI is commonly used to ascertain measures of structure (T 2 and T 1 ) and function (apparent diffusion coefficient [ADC, which measures the diffusion rate of water molecules] and cerebral blood flow [CBF]). Further, scientists are investigating whether molecular MRI techniques can be used to assess some neurologic diseases and their response to therapy (Amyot et al, 2015; Zhou et al, 2003, 2011). For example, it has recently been shown that protein-based amide proton transfer (APT) MRI can accurately detect hyperacute intracerebral hemorrhage and distinctly differentiate intracerebral hemorrhage from cerebral ischemia in rats (Wang et al, 2015).…”