Diffusion tensor imaging biomarkers for traumatic axonal injury: analysis of three analytic methods.
Traumatic axonal injury (TAI) is a common mechanism of traumatic brain injury not readily identified using conventional neuroimaging modalities. Novel imaging modalities such as diffusion tensor imaging (DTI) can detect microstructural compromise in white matter (WM) in various clinical populations including TAI. DTI-derived data can be analyzed using global methods (i.e., WM histogram or voxel-based approaches) or a regional approach (i.e., tractography). While each of these methods produce qualitatively comparable results, it is not clear which is most useful in clinical research and ultimately in clinical practice. This study compared three methods of analyzing DTI-derived data with regard to detection of WM injury and their association with clinical outcomes. Thirty patients with TAI and 19 demographically similar normal controls were scanned using a 3 Tesla magnet. Patients were scanned approximately eight months postinjury, and underwent an outcomes assessment at that time. Histogram analysis of fractional anisotropy (FA) and mean diffusivity showed global WM integrity differences between patients and controls. Voxel-based and tractography analyses showed significant decreases in FA within centroaxial structures involved in TAI. All three techniques were associated with functional and cognitive outcomes. DTI measures of microstructural integrity appear robust, as the three analysis techniques studied showed adequate utility for detecting WM injury.
Center for Brain Health, University of Texas at Dallas, Richardson, Texas 75390, USA.
Carlos D
CD
Marquez de la Plata
Fanpei Gloria
FG
Yang
Jun Yi
JY
Wang
Kamini
K
Krishnan
Khamid
K
Bakhadirov
Christopher
C
Paliotta
Sina
S
Aslan
Michael D
MD
Devous
Carol
C
Moore
Caryn
C
Harper
Roderick
R
McColl
C
C
Munro Cullum
Ramon
R
Diaz-Arrastia
D000293:Adolescent; D000328:Adult; D016880:Anisotropy; D001921:Brain / Q000473:pathology*; D001930:Brain Injuries / Q000175:diagnosis*; D001931:Brain Mapping; D015331:Cohort Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012720:Severity of Illness Index; D055815:Young Adult