Department of Neurology, University of Würzburg, Würzburg, Germany.
Curr Opin Neurol. 2010 Jun;23(3):282-6. doi: 10.1097/WCO.0b013e328337f4b5.
Inflammation is an important component not only in autoimmune but also in ischemic/degenerative disorders of the central nervous system (CNS). We here review magnetic resonance imaging (MRI)-based techniques to visualize neuroinflammation in vivo.
Iron oxide particles such as superparamagnetic iron oxide (SPIO) and ultrasmall SPIO (USPIO) are phagocytosed by hematogeneous macrophages upon systemic application into the circulation and allow in-vivo tracking of infiltration to the CNS due to their paramagnetic effect by MRI in experimental CNS disorders, and also in multiple sclerosis and stroke. Thereby, the size and application scheme of the iron particles is critical for interpretation of the MRI data which in addition to neuroinflammation involves passive diffusion and intravascular trapping. Targeting of inflammatory, activation-dependent enzymes such as myeloperoxidase or immune function molecules by MR contrast agents represents a molecular approach to visualize critical steps of lesion development caused by neuroinflammation. Clinical studies with Gd-DTPA in conjunction with experimental investigations employing more sensitive MR contrast agents such as gadofluorine revealed that breakdown of the blood-brain barrier and SPIO/USPIO-related macrophage infiltration occur mostly independently.
Cellular and targeted molecular MRI provides important insights into the dynamics of neuroinflammation.
炎症不仅是自身免疫性疾病，也是中枢神经系统（CNS）缺血/变性疾病的一个重要组成部分。我们在此综述基于磁共振成像（MRI）的技术，以活体可视化神经炎症。
超顺磁氧化铁（SPIO）和超小超顺磁氧化铁（USPIO）等氧化铁颗粒在全身应用于循环系统后被血源性巨噬细胞吞噬，并由于其顺磁性作用，通过 MRI 在实验性 CNS 疾病中以及多发性硬化症和中风中，可在体内追踪到对 CNS 的浸润。因此，铁颗粒的大小和应用方案对于 MRI 数据的解释至关重要，因为这些数据不仅涉及神经炎症，还涉及被动扩散和血管内滞留。通过 MRI 对比剂靶向炎症、激活依赖性酶（如髓过氧化物酶）或免疫功能分子，是可视化神经炎症引起的病变发展关键步骤的分子方法。与采用更敏感的 MRI 对比剂（如钆氟化物）的实验研究相结合的 Gd-DTPA 临床研究表明，血脑屏障的破坏和 SPIO/USPIO 相关的巨噬细胞浸润大多是独立发生的。
细胞和靶向分子 MRI 为神经炎症的动态变化提供了重要的见解。
