@article{ref1,
title="Hybrid diffusion imaging in mild traumatic brain injury",
journal="Journal of neurotrauma",
year="2018",
author="Wu, Yu-Chien and Mustafi, Sourajit Mitra and Harezlak, Jaroslaw and Kodiweera, Chandana and Flashman, Laura A. and McAllister, Thomas",
volume="35",
number="20",
pages="2377-2390",
abstract="Mild traumatic brain injury (mTBI) is an important public health problem. Although conventional medical imaging techniques can detect moderate-to-severe injuries, they are relatively insensitive to mTBI. In this study, we used hybrid diffusion imaging (HYDI) to detect white-matter alterations in nineteen patients with mTBI and 23 other trauma-control patients. Within 15 days (SD=10) of brain injury, all subjects underwent magnetic-resonance HYDI and were assessed with battery of neuropsychological tests of sustained attention, memory, and executive function. Tract-based spatial statistics (TBSS) were used for voxelwise statistical analyses within the white-matter skeleton to study between-group differences in diffusion metrics, within-group correlations between diffusion metrics and clinical outcomes, and between group interaction effects. The advanced diffusion imaging techniques including neurite orientation dispersion and density imaging (NODDI) and q-space analyses appeared to be more sensitive then classic diffusion tensor imaging (DTI). Only NODDI-derived intra-axonal volume fraction (V<sub>ic</sub>) demonstrated significant group differences (i.e., 5% to 9% lower in the injured brain). Within the mTBI group, V<sub>ic</sub> and a q-space measure, P<sub>0</sub>, correlated with 6 of 10 neuropsychological tests including measures of attention, memory, and executive function. In addition, the direction of correlations differed significantly between the groups (R<sup>2</sup> > 0.71 and P<sub>interation</sub> < 0.03). Specifically, in the control group, higher V<sub>ic</sub> and P<sub>0</sub> were associated with better performances on clinical assessments, whereas in the mTBI group, higher V<sub>ic</sub> and P<sub>0</sub> were associated with worse performances with correlation coefficients > 0.83. In summary, the NODDI-derived axonal density index and q-space measure for tissue restriction demonstrated superior sensitivity to white-matter changes shortly after mTBI. These techniques hold promise as a neuroimaging biomarker for mTBI.<p /> <p>Language: en</p>",
language="en",
issn="0897-7151",
doi="10.1089/neu.2017.5566",
url="http://dx.doi.org/10.1089/neu.2017.5566"
}