title: Maximum principal strain and strain rate associated with concussion diagnosis correlates with changes in corpus callosum white matter indices.
abstract: On-field monitoring of head impacts, combined with finite element (FE) biomechanical simulation, allow for predictions of regional strain associated with a diagnosed concussion. However, attempts to correlate these predictions with in vivo measures of brain injury have not been published. This article reports an approach to and preliminary results from the correlation of subject-specific FE model-predicted regions of high strain associated with diagnosed concussion and diffusion tensor imaging to assess changes in white matter integrity in the corpus callosum (CC). Ten football and ice hockey players who wore instrumented helmets to record head impacts sustained during play completed high field magnetic resonance imaging preseason and within 10 days of a diagnosed concussion. The Dartmouth Subject-Specific FE Head model was used to generate regional predictions of strain and strain rate following each impact associated with concussion. Maps of change in fractional anisotropy (FA) and median diffusivity (MD) were generated for the CC of each athlete to correlate strain with change in FA and MD. Mean and maximum strain rate correlated with change in FA (Spearman ρ = 0.77, p = 0.01; 0.70, p = 0.031), and there was a similar trend for mean and maximum strain (0.56, p = 0.10; 0.6, p = 0.07), as well as for maximum strain with change in MD (-0.63, p = 0.07). Change in MD correlated with injury-to-imaging interval (ρ = -0.80, p = 0.006) but change in FA did not (ρ = 0.18, p = 0.62). These results provide preliminary confirmation that model-predicted strain and strain rate in the CC correlate with changes in indices of white matter integrity.
authors: Department of Psychiatry, Section of Neuropsychiatry, Dartmouth Medical School, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA. thomas.w.mcallister@dartmouth.edu
authors: Thomas W
authors: TW
authors: McAllister
authors: James C
authors: JC
authors: Ford
authors: Songbai
authors: S
authors: Ji
authors: Jonathan G
authors: JG
authors: Beckwith
authors: Laura A
authors: LA
authors: Flashman
authors: Keith
authors: K
authors: Paulsen
authors: Richard M
authors: RM
authors: Greenwald
mesh_terms: D000054:Acceleration; D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000175:diagnosis* / Q000503:physiopathology; D001924:Brain Concussion / Q000175:diagnosis* / Q000503:physiopathology; D003337:Corpus Callosum / Q000293:injuries* / Q000503:physiopathology; D020342:Finite Element Analysis; D005538:Football / Q000293:injuries*; D006260:Head Protective Devices; D006688:Hockey / Q000293:injuries*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008954:Models, Biological; D009513:New Hampshire; D012399:Rotation; D012574:Schools; D019876:Sports Equipment; D013686:Telemetry; D055815:Young Adult