Movement Disorders Program, Division of Neurology, University of Alberta, Edmonton, AB, Canada.
Parkinsonism Relat Disord. 2009 Dec;15 Suppl 3:S215-8. doi: 10.1016/S1353-8020(09)70818-1.
Biochemical studies have reported increased iron content in the substantia nigra pars compacta (SNc) in Parkinson disease (PD), with changes most marked in severe disease, suggesting that measurement of regional iron content in the nigra may provide an indication of the pathologic severity of the disease. Although basal ganglia structures, including the substantia nigra, are readily visualized with MRI, in part because of their high iron content, conventional imaging techniques have failed to show definitive abnormalities in individuals with PD. We have developed MRI-based methodology to estimate regional iron content utilizing a 1.5 tesla system and have shown a correlation between age and striatal iron, as well as a significant increase in putaminal and pallidal iron in PD that correlated with the severity of clinical symptomatology. Several investigators have utilized novel MR techniques implemented on 3 tesla magnets and have suggested the presence of increased nigral iron content in treated patients with PD, in addition to a correlation between nigral iron and simple reaction time. We have applied a modification of our original method to determine whether SNc changes evident at 3 tesla corresponded anatomically to the distribution of neuropathologic changes reported previously. Our results indicate the presence of lateral SNc abnormalities in untreated patients with early PD, consistent with increased iron content and corresponding to the known distribution of neuronal loss occurring in this disorder. We suggest that this may ultimately provide an imaging marker for disease progression in PD, although longitudinal studies are required.
生化研究报告称，帕金森病（PD）患者的黑质致密部（SNc）铁含量增加，在疾病严重程度时变化最为明显，这表明测量黑质的区域铁含量可能可以提示疾病的病理严重程度。虽然基底节结构（包括黑质）可以通过 MRI 轻松显示，部分原因是其铁含量高，但常规成像技术未能在 PD 患者中显示出明确的异常。我们已经开发了基于 MRI 的方法来利用 1.5 特斯拉系统估计区域铁含量，并显示出年龄与纹状体铁之间的相关性，以及 PD 患者纹状体铁和苍白球铁的显著增加，这与临床症状的严重程度相关。一些研究人员利用在 3 特斯拉磁体上实施的新的磁共振技术，并提出在接受治疗的 PD 患者中存在增加的黑质铁含量，此外，黑质铁与简单反应时间之间存在相关性。我们应用了我们原始方法的修改版，以确定在 3 特斯拉时明显的 SNc 变化是否在解剖学上与先前报道的神经病理学变化的分布相对应。我们的结果表明，未经治疗的早期 PD 患者存在 SNc 外侧异常，这与铁含量增加一致，与该疾病中发生的神经元丧失的已知分布相对应。我们建议，这可能最终为 PD 中的疾病进展提供影像学标志物，尽管需要进行纵向研究。
