体素内不相干运动扩散加权成像在脑膜瘤中的初步临床研究

摘要

目的 探讨体素内不相干运动扩散加权磁共振成像(IVIM-MRI)单、双指数模型在脑膜瘤中的应用价值.方法 纳入20例经手术切除及病理结果证实为脑膜瘤的病例,均于术前行常规MRI及IVIM-MRI扫描,测量肿瘤实质区及正常脑白质区单指数模型下表观扩散系数ADC值和双指数模型下纯扩散系数D值、灌注分数f值、灌注系数D*值,分析脑膜瘤的IVIM-MRI成像特点.结果 单指数模型中,肿瘤实质区ADC值较正常脑白质ADC值低,但两者差异无统计学意义(t=0.514,P＞0.05);双指数模型中,肿瘤实质区与正常脑白质区D值差异有统计学意义(t=3.043,P＜0.01);而D*值和f值差异无统计学意义(t=1.274、0.220,均P＞0.05).4种不同病理类型脑膜瘤比较,单指数模型下ADC值及双指数模型下D、f值均有显著差异(F=5.232、5.674、14.058,均P＜0.01).结论 IVIM-MRI能够准确描述脑膜瘤扩散信息,并同时获得脑膜瘤灌注信息,可考虑作为一种无创性脑肿瘤灌注检查方法.%Objective To evaluate the application value of the mono-exponential model and bi-exponential model of intravoxel incoherent motion diffusion-weighted MRI (IVIM-MRI) in meningiomas.Methods Twenty meningioma patients confirmed by surgical pathology were brought into this study,and received routine MRI and IVIM-MRI scan.The apparent diffusion coefficient (ADC) of mono-exponential model and the diffusion coefficient (D),pseudo perfusion coefficient (D*) and the perfusion fraction (f) of bi-exponential model were measured both in tumor and normal white matter (NWM) areas,then the IVIM-MRI feature of meningioma was analyzed.Results In mono-exponential model,ADC value was lower in the tumor area than in NWM area,but the difference was not statistically significant (t =0.514,P ＞ 0.05).In bi-exponential model,the difference in D value was statistically significant between tumor and NWM areas (t =3.043,P ＜ 0.01),while there was no significant difference in D* and f values between tumor and NWM areas (t =1.274,0.220,P ＞ 0.05).Otherwise,there were significant differences in ADC,D,f values between the four different pathological subtypes of meningiomas (F =5.232,5.674,14.058,P ＜ 0.01).Conclusion IVIM-MRI can get the accurate perfusion and diffusion informations of meningiomas,and can be considered as a noninvasive perfusion method for brain tumors.