Neuroimaging Research Unit, Division of Neuroscience, Institute of Experimental Neurology, , San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.
J Neurol Neurosurg Psychiatry. 2014 Jan;85(1):60-6. doi: 10.1136/jnnp-2013-305246. Epub 2013 Jun 27.
In multiple sclerosis (MS), MRI is the most important paraclinical tool used to inform diagnosis and for monitoring disease evolution, either natural or modified by treatment. The increased availability of ultra-high-field magnets (7 Tesla or higher) gives rise to questions about the main benefits of and challenges for their use in patients with MS. The main advantages of ultra-high-field MRI are the improved signal-to-noise ratio, greater chemical shift dispersion, and improved contrast due to magnetic susceptibility variations, which lead to increased sensitivity to the heterogeneous pathological substrates of the disease. At present, ultra-high-field MRI is mainly used to improve our understanding of MS pathogenesis. This review discusses the main achievements that have so far come from the use of these scanners, which are: better visualisation of white matter lesions and their morphological characteristics; an improvement in the ability to visualise grey matter lesions and their exact location; the quantification of 'novel' metabolites which may have a role in axonal degeneration; and greater sensitivity to iron accumulation. The application of ultra-high-field systems in standard clinical practice is still some way off since their role in the diagnostic work-up of patients at presentation with clinically isolated syndromes, or in monitoring disease progression or treatment response in patients with definite MS, needs to be established. Additional challenges remain in the development of morphological, quantitative and functional imaging methods at these field strengths, techniques which may ultimately lead to novel biomarkers for monitoring disease evolution and treatment response.
在多发性硬化症（MS）中，MRI 是用于辅助诊断和监测疾病进展（包括自然进展和治疗干预后的改变）的最重要的辅助检查手段。超高磁场（7 特斯拉或更高）的应用日益广泛，由此带来了一些问题，包括超高磁场 MRI 应用于 MS 患者的主要获益和挑战有哪些。超高磁场 MRI 的主要优势在于其信噪比提高、化学位移弥散度增加、磁敏感性变化导致的对比增强，这使得其对疾病的异质性病理基础具有更高的敏感性。目前，超高磁场 MRI 主要用于帮助我们深入理解 MS 的发病机制。本文讨论了迄今为止使用这些扫描仪所取得的主要成果，包括：更好地显示白质病变及其形态学特征；提高显示灰质病变及其确切位置的能力；量化可能与轴突变性有关的“新型”代谢物；提高铁沉积的检测灵敏度。超高磁场系统在标准临床实践中的应用还有待进一步探索，因为其在表现为临床孤立综合征的患者的诊断评估、以及在监测明确 MS 患者的疾病进展或治疗反应中的作用尚需进一步明确。在这些场强下开发形态学、定量和功能成像方法仍然存在一些挑战，这些方法可能最终会为监测疾病演变和治疗反应提供新的生物标志物。
