Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, No. 600, Yi Shan Road, Shanghai 200233, China.
Department of Neurosurgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai Jiao Tong University School of Medicine, No. 600, Yi Shan Road, Shanghai 200233, China.
Neuroscience. 2018 Nov 10;392:180-189. doi: 10.1016/j.neuroscience.2018.09.030. Epub 2018 Sep 29.
This study aims to investigate the value of diffusion kurtosis imaging (DKI) in assessing microstructural changes associated with cognitive impairment in chronic traumatic brain injury (TBI). At 7 months, six TBI rats and six control rats underwent Morris water maze (MWM) tests, followed by DKI examinations. DKI parameters were measured in bilateral cortex, hippocampus, and callosum. Brain immunohistochemistry (IHC) analysis of neuron [neuron-specific nuclear protein (NeuN)], astroglia [glial fibrillary acidic protein (GFAP)], microglia [ionized calcium binding adaptor molecule 1 (Iba-1)], and myelin [myelin basic protein (MBP)] was performed in the same area as DKI parameter. The DKI parameters, IHC results, and MWM results were compared between TBI and control groups. Correlation analysis was performed to analyze the relationship between DKI parameters and IHC and MWM results. TBI group had worse performance in MWM test. DKI showed higher mean diffusion (MD) in all ipsilateral regions of interest (ROIs), and lower mean kurtosis (MK) in ipsilateral cortex and callosum in TBI group (P < 0.05). TBI group also showed lower IHC staining of NeuN, and higher staining of Iba-1 and MBP in all ipsilateral ROIs (P < 0.05). Further correlational study showed a positive relationship between MK and NeuN, MD and MBP in ipsilateral cortex, and a negative relationship between MK and Iba-1, MBP in ipsilateral cortex and hippocampus (P < 0.05). The MK in ipsilateral cortex and hippocampus were also correlated with MWM test results (P < 0.05). Our study suggests that DKI could be used to assess the microstructural changes associated with cognitive impairment in chronic TBI.
本研究旨在探讨扩散峰度成像（DKI）在评估慢性创伤性脑损伤（TBI）相关认知障碍的微观结构变化中的价值。在 7 个月时，6 只 TBI 大鼠和 6 只对照大鼠进行了 Morris 水迷宫（MWM）测试，然后进行了 DKI 检查。在双侧皮质、海马和胼胝体中测量了 DKI 参数。在 DKI 参数测量的同一区域进行了神经元[神经元特异性核蛋白（NeuN）]、星形胶质细胞[胶质纤维酸性蛋白（GFAP）]、小胶质细胞[离子钙结合接头蛋白 1（Iba-1）]和髓鞘[髓鞘碱性蛋白（MBP）]的免疫组织化学（IHC）分析。将 TBI 组和对照组之间的 DKI 参数、IHC 结果和 MWM 结果进行了比较。进行了相关性分析以分析 DKI 参数与 IHC 和 MWM 结果之间的关系。TBI 组在 MWM 测试中的表现更差。DKI 显示所有同侧感兴趣区域（ROI）的平均扩散（MD）更高，TBI 组同侧皮质和胼胝体的平均峰度（MK）更低（P<0.05）。TBI 组还显示同侧 ROI 中 NeuN 的 IHC 染色减少，Iba-1 和 MBP 的染色增加（P<0.05）。进一步的相关性研究表明，MK 与同侧皮质中的 NeuN 呈正相关，MD 与同侧皮质和海马中的 MBP 呈正相关，MK 与同侧皮质和海马中的 Iba-1 和 MBP 呈负相关（P<0.05）。同侧皮质和海马的 MK 也与 MWM 测试结果相关（P<0.05）。我们的研究表明，DKI 可用于评估慢性 TBI 相关认知障碍的微观结构变化。
