Zhu David C, Covassin Tracey, Nogle Sally, Doyle Scarlett, Russell Doozie, Pearson Randolph L, Monroe Jeffrey, Liszewski Christine M, DeMarco J Kevin, Kaufman David I
1 Department of Radiology, Michigan State University , East Lansing, Michigan.
J Neurotrauma. 2015 Mar 1;32(5):327-41. doi: 10.1089/neu.2014.3413. Epub 2014 Dec 16.
Current diagnosis and monitoring of sports-related concussion rely on clinical signs and symptoms, and balance, vestibular, and neuropsychological examinations. Conventional brain imaging often does not reveal abnormalities. We sought to assess if the longitudinal change of functional and structural connectivity of the default-mode network (DMN) can serve as a potential biomarker. Eight concussed Division I collegiate football student-athletes in season (one participated twice) and 11 control subjects participated in this study. ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) was administered over the course of recovery. High-resolution three dimensional T1-weighted, T2*-weighted diffusion-tensor images and resting-state functional magnetic resonance imaging (rs-fMRI) scans were collected from each subject within 24 h, 7±1 d and 30±1 d after concussion. Both network based and whole-brain based functional correlation analyses on DMN were performed. ImPACT findings demonstrated significant cognitive impairment across multiple categories and a significant increase of symptom severity on Day 1 following a concussion but full recovery by 6.0±2.4 d. While the structural connectivity within DMN and gross anatomy appeared unchanged, a significantly reduced functional connectivity within DMN from Day 1 to Day 7 was found in the concussed group in this small pilot study. This reduction was seen in eight of our nine concussion cases. Compared with the control group, there appears a general trend of increased DMN functional connectivity on Day 1, a significant drop on Day 7, and partial recovery on Day 30. The results of this pilot study suggest that the functional connectivity of DMN measured with longitudinal rs-fMRI can serve as a potential biomarker to monitor the dynamically changing brain function after sports-related concussion, even in patients who have shown clinical improvement.
目前，与运动相关的脑震荡的诊断和监测依赖于临床体征和症状，以及平衡、前庭和神经心理学检查。传统的脑部成像通常无法显示异常情况。我们试图评估默认模式网络（DMN）的功能和结构连接的纵向变化是否可以作为一种潜在的生物标志物。八名在赛季中脑震荡的一级大学橄榄球学生运动员（其中一名参与了两次）和11名对照受试者参与了这项研究。在恢复过程中进行了ImPACT（脑震荡后即刻评估和认知测试）。在脑震荡后24小时、7±1天和30±1天内，从每个受试者收集高分辨率三维T1加权、T2*加权扩散张量图像和静息态功能磁共振成像（rs-fMRI）扫描。对DMN进行了基于网络和基于全脑的功能相关性分析。ImPACT结果显示，脑震荡后第1天，多个类别存在明显的认知障碍，症状严重程度显著增加，但在6.0±2.4天内完全恢复。虽然DMN内的结构连接和大体解剖结构似乎没有变化，但在这项小型初步研究中，脑震荡组在第1天到第7天发现DMN内的功能连接显著降低。在我们的9例脑震荡病例中有8例出现了这种降低。与对照组相比，DMN功能连接在第1天有普遍增加的趋势，第
