Department of Radiology, New York University School of Medicine, New York, USA.
AJNR Am J Neuroradiol. 2011 Nov-Dec;32(10):1851-6. doi: 10.3174/ajnr.A2637. Epub 2011 Sep 1.
Experimental studies have suggested a role for iron accumulation in the pathology of TBI. Magnetic field correlation MR imaging is sensitive to the presence of non-heme iron. The aims of this study are to 1) assess the presence, if any, and the extent of iron deposition in the deep gray matter and regional white matter of patients with mTBI by using MFC MR imaging; and 2) investigate the association of regional brain iron deposition with cognitive and behavioral performance of patients with mTBI.
We prospectively enrolled 28 patients with mTBI. Eighteen healthy subjects served as controls. The subjects were administered the Stroop color word test, the Verbal Fluency Task, and the Post-Concussion Symptoms Scale. The MR imaging protocol (on a 3T imager) consisted of conventional brain imaging and MFC sequences. After the calculation of parametric maps, MFC was measured by using a region of interest approach. MFC values across groups were compared by using analysis of covariance, and the relationship of MFC values and neuropsychological tests were evaluated by using Spearman correlations.
Compared with controls, patients with mTBI demonstrated significant higher MFC values in the globus pallidus (P = .002) and in the thalamus (P = .036). In patients with mTBI, Stroop test scores were associated with the MFC value in frontal white matter (r = -0.38, P = .043).
MFC values were significantly elevated in the thalamus and globus pallidus of patients with mTBI, suggesting increased accumulation of iron. This supports the hypothesis that deep gray matter is a site of injury in mTBI and suggests a possible role for iron accumulation in the pathophysiological events after mTBI.
实验研究表明铁积累在 TBI 病理中起作用。磁场相关磁共振成像（MFC MR 成像）对非血红素铁的存在敏感。本研究的目的是 1）通过 MFC MR 成像评估 mTBI 患者深部灰质和区域性白质中是否存在铁沉积及沉积程度；2）探讨 mTBI 患者脑内铁沉积与认知和行为表现的相关性。
我们前瞻性纳入 28 例 mTBI 患者。18 例健康受试者作为对照组。受试者接受 Stroop 颜色词测试、言语流畅性任务和脑震荡后症状量表（Post-Concussion Symptoms Scale）评估。MR 成像方案（在 3T 成像仪上）包括常规脑成像和 MFC 序列。在计算参数图后，使用感兴趣区方法测量 MFC。采用协方差分析比较各组间 MFC 值的差异，采用 Spearman 相关评估 MFC 值与神经心理学测试的相关性。
与对照组相比，mTBI 患者的苍白球（P =.002）和丘脑（P =.036）的 MFC 值显著升高。在 mTBI 患者中，Stroop 测试分数与额叶白质的 MFC 值呈负相关（r = -0.38，P =.043）。
mTBI 患者的丘脑和苍白球的 MFC 值显著升高，提示铁积累增加。这支持深部灰质是 mTBI 损伤部位的假说，并提示铁积累可能在 mTBI 后的病理生理事件中起作用。
