磁共振弥散张量成像对良 恶性脑膜瘤诊断的初探

The primary study in differentiation of benign and malignant meningiomas with diffusion tensor imaging

目的运用磁共振弥散张量成像(DTI)测量脑膜瘤表现弥散系数(ADC)值、FA值和白质纤维走行图,探讨其对良、恶性脑膜瘤的诊断价值。方法对23例良性脑膜瘤,4例恶性脑膜瘤行弥散张量成像,分别测量肿瘤实质区、瘤周水肿区和瘤周白质区的ADC值和FA值,并根据原始图像重建双侧白质纤维走行图。结果①良、恶性脑膜瘤肿瘤实质区ADC值比较差异有统计学意义;良、恶性脑膜瘤瘤周白质FA值差异有统计学意义。②良性脑膜瘤瘤周白质表现为纤维束受压移位或无明显变化;恶性脑膜瘤瘤周水肿区、瘤周白质均出现较明显的纤维束缺失。结论ADC值和FA值有助于脑膜瘤良、恶性的鉴别;白质纤维走行图能清晰显示肿瘤与白质纤维束的关系。

Objective To investigate the value of ADC values, FA values, fiber tracking maps in differentiating malignant from benign meningiomas by using DWI and diffusion tensor imaging （DTI）. Methods Twenty-three of benign meningiomas and 4 cases of malignant meningiomas with pathologic confirmation underwent DTI. ADC and FA values were measured in the solid part of tumors, the peritumoral edema and the white matter surrounding the edema. Bilateral white matter were 3D reconstructed. Result ① The difference of ADC values in the solid part of tumors was statistically significant between malignant meningiomas and benign tumors. There was significant difference of FA values in white matter surrounding the edema between malignant meningiomas and benign tumors. ② Benign meningiomas led to a corresponding large displacement of the fiber away from the tumor or the fiber was not seen to be separate from the tumor obviously. The fiber of malignant meningiomas is not only displaced but infiltrated by the tumor. Conclusion ADC and FA values may differentiate the malignant from benign meningiomas. Fiber tracking maps provide the information regarding the detailed relationship between meningiomas and nearby white matter tracts.