中文摘要：

目的 MR体素内不相干运动（IVIM）成像是一种无创、定量评估组织微环境的扩散及灌注特点的成像方法。本研究旨在探讨IVIM在复发-缓解型多发性硬化（RRMS）诊断中的应用价值。资料与方法回顾性分析2015年6月-2016年1月重庆医科大学附属第一医院确诊的27例RRMS患者的临床资料。所有患者均行常规MRI和IVIM扫描,取多个b值（10、20、30、40、50、100、150、200、350、500、650、800、1000 s/mm^2）,获取反映RRMS病灶及白质（NAWM）区组织扩散特点的表观扩散系数（ADC）、ADC（slow）、ADC（fast）及组织微血管灌注分数（f）。结果非强化病灶区、病灶旁NAWM区与远离病灶的NAWM区两两比较,非强化病灶区ADC、ADC（slow）、ADC（fast）、f值明显高于病灶旁及远离病灶的NAWM区,差异均有统计学意义（P〈0.05）。但病灶旁NAWM区与远离病灶的NAWM区比较,差异均无统计学意义（P〉0.05）。结论 MR IVIM成像可定量分析RRMS病灶与NAWM区组织的扩散及灌注特点,有助于推测病灶的病理改变,为损伤分类及鉴别提供帮助。

英文摘要：

Purpose Intravoxel incoherent motion（IVIM） MR is a method developed in recent years which can quantitatively evaluate the diffusion and perfusion characteristics of microenvironment. The aim of this study was to investigate the application value of IVIM in assessing relapsing-remitting multiple sclerosis（RRMS）. Materials and Methods A retrospective analysis of the clinical data of 27 patients with RRMS confirmed clinically at the First Affiliated Hospital of Chongqing Medical University from Jun. 2015 to Jan. 2016 was carried out in the study. All the patients underwent the conventional MRI and IVIM MRI based on multi-b-factor（b values of 10, 20, 30, 40, 50, 100, 150, 200, 350, 500, 650, 800, 1000 s/mm~2） with 3.0T MR scanner. The apparent diffusion coefficient（ADC）, ADC（slow）, ADC（fast） and f values were evaluated since they could reflect the diffusion and perfusion status of RRMS lesions and normal-appearing white matter（NAWM） regions. Results The ADC, ADCslow, ADCfast and f values of the non-enhancing（NE） lesions were significantly higher than those in the NAWM regions both near and far from NE lesions（P〈0.05）. However, the ADC, ADC（slow）, ADC（fast） and f values in the NAWM regions close to the NE lesions had no significant differences with those in the NAWM regions far from the lesions（P〉0.05）. Conclusion The IVIM MRI can measure the diffusion and perfusion status of the lesions and NAWM in RRMS patients, which, therefore, is helpful in speculation of the pathological changes of RRMS lesions and in its injury classification and identification.