Department of Psychiatry, Section of Neuropsychiatry, Dartmouth Medical School, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756, USA.
Ann Biomed Eng. 2012 Jan;40(1):127-40. doi: 10.1007/s10439-011-0402-6. Epub 2011 Oct 13.
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.
现场监测头部撞击，并结合有限元（FE）生物力学模拟，可以预测与诊断性脑震荡相关的区域应变。然而，尚未有文献尝试将这些预测与脑损伤的体内测量值相关联。本文报告了一种方法以及初步结果，即将与诊断性脑震荡相关的特定于受试者的 FE 模型预测的高应变区域与弥散张量成像（DTI）相关联，以评估胼胝体（CC）中白质完整性的变化。10 名橄榄球和冰球运动员在比赛中佩戴了可记录头部撞击的仪器头盔，在赛季前和诊断性脑震荡后 10 天内完成了高磁场磁共振成像检查。使用 Dartmouth 特定于受试者的 FE 头部模型生成与脑震荡相关的每次撞击后的应变和应变速率的区域预测。为每位运动员的 CC 生成各向异性分数（FA）和平均弥散度（MD）变化图，以关联应变与 FA 和 MD 的变化。平均和最大应变速率与 FA 的变化相关（Spearman ρ = 0.77，p = 0.01；0.70，p = 0.031），而平均和最大应变也有类似的趋势（0.56，p = 0.10；0.6，p = 0.07），最大应变与 MD 的变化也有类似的趋势（-0.63，p = 0.07）。MD 的变化与从受伤到成像的时间间隔相关（ρ = -0.80，p = 0.006），但 FA 的变化与 MD 的变化不相关（ρ = 0.18，p = 0.62）。这些结果初步证实了 CC 中模型预测的应变和应变速率与白质完整性指数的变化相关。
