From Aix-Marseille Université (E.V.O., S.M., A.l.T., V.H.P., P.V., M.G., J.-P.R., J.P., O.G., G.D.), Centre de Résonance Magnétique Biologique et Médicale (CRMBM), UMR 7339 Centre National de Recherche Scientifique (CNRS), Marseille, France.
Department of Radiology (G.V., D.C.A.), Division of MR Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts.
AJNR Am J Neuroradiol. 2018 Apr;39(4):634-641. doi: 10.3174/ajnr.A5563. Epub 2018 Feb 22.
Inhomogeneous magnetization transfer is a new endogenous MR imaging contrast mechanism that has demonstrated high specificity for myelin. Here, we tested the hypothesis that inhomogeneous magnetization transfer is sensitive to pathology in a population of patients with relapsing-remitting MS in a way that both differs from and complements conventional magnetization transfer.
Twenty-five patients with relapsing-remitting MS and 20 healthy volunteers were enrolled in a prospective MR imaging research study, whose protocol included anatomic imaging, standard magnetization transfer, and inhomogeneous magnetization transfer imaging. Magnetization transfer and inhomogeneous magnetization transfer ratios measured in normal-appearing brain tissue and in MS lesions of patients were compared with values measured in control subjects. The potential association of inhomogeneous magnetization transfer ratio variations with the clinical scores (Expanded Disability Status Scale) of patients was further evaluated.
The magnetization transfer ratio and inhomogeneous magnetization transfer ratio measured in the thalami and frontal, occipital, and temporal WM of patients with MS were lower compared with those of controls ( < .05). The mean inhomogeneous magnetization transfer ratio measured in lesions was lower than that in normal-appearing WM ( < .05). Significant ( < .05) negative correlations were found between the clinical scores and inhomogeneous magnetization transfer ratio measured in normal-appearing WM structures. Weaker nonsignificant correlation trends were found for the magnetization transfer ratio.
The sensitivity of the inhomogeneous magnetization transfer technique for MS was highlighted by the reduction in the inhomogeneous magnetization transfer ratio in MS lesions and in normal-appearing WM of patients compared with controls. Stronger correlations with the Expanded Disability Status Scale score were obtained with the inhomogeneous magnetization transfer ratio compared with the standard magnetization transfer ratio, which may be explained by the higher specificity of inhomogeneous magnetization transfer for myelin.
不均匀磁化转移是一种新的内源性磁共振成像对比机制，对髓鞘具有高度特异性。在这里，我们检验了这样一个假设，即在一个复发缓解型多发性硬化症患者群体中，不均匀磁化转移对病理学的敏感性与传统的磁化转移不同且互补。
25 例复发缓解型多发性硬化症患者和 20 名健康志愿者参与了一项前瞻性磁共振成像研究，其方案包括解剖成像、标准磁化转移和不均匀磁化转移成像。在患者的正常表现脑组织和 MS 病变中测量的磁化转移和不均匀磁化转移比与对照组测量的值进行比较。进一步评估不均匀磁化转移比变化与患者临床评分（扩展残疾状况量表）之间的潜在相关性。
与对照组相比，MS 患者丘脑及额、顶、颞叶白质的磁化转移比和不均匀磁化转移比均降低（<0.05）。病变中测量的平均不均匀磁化转移比低于正常表现白质（<0.05）。与正常表现白质结构中测量的临床评分之间存在显著的（<0.05）负相关。对于磁化转移比，发现了较弱的非显著相关趋势。
与对照组相比，MS 患者病变和正常表现白质中不均匀磁化转移比的降低突出了不均匀磁化转移技术对 MS 的敏感性。与标准磁化转移比相比，不均匀磁化转移比与扩展残疾状况量表评分之间获得了更强的相关性，这可能是由于不均匀磁化转移对髓鞘的特异性更高。
