高级别星形细胞瘤弥散张量成像的临床应用研究

Diffusion tensor imaging of high-grade astrocytomas

目的探讨磁共振弥散张量成像(Diffusion tensor imaging,DTI)对高级别星形细胞瘤的诊断价值。方法经病理证实的高级别星形细胞瘤12例,行常规MR平扫、增强扫描及DTI检查。在ADC图和FA图上分别肿瘤周围水肿区、肿瘤强化区、邻近区域正常脑白质ADC值及FA值,在FA图上明确肿瘤与正常脑白质关系。结果水肿区、肿瘤强化区ADC值和FA值与正常脑白质区比较差异均有显著性。水肿区与肿瘤强化区之间比较,ADC值差异有显著性,FA值差异无显著。FA图上可清楚显示肿瘤实质区脑白质纤维破坏及与周围正常脑白质关系。结论ADC值及FA值能帮助区分肿瘤实质区、瘤周水肿区与正常脑白质区,FA图能明确肿瘤与周围正常脑白质关系。

Objective To evaluate the diagnostic merit of diffusion tensor imaging for high-grade astrocytomas. Methods 12 patients with pathological grade Ⅲ -Ⅳ astrocytomas underwent conventional MRI, contrast-enhanced MRI and DTI. ADC value and FA value were calculated in area of enhancing tumor,edema and normal white matter respectively both on the ADC map and FA map. On the FA map, the relation between tumor and normal white matter was determined. Results There was significant difference of ADC value and FA value in the edema and enhancing tumor area compared to the normal white matter （P〈0. 05）. And between edema and enhancing tumor area, there was also significant difference on ADC value （P〈0. 05）. FA value did not show apparent difference among them（P〉0. 05）. The relation between white matter fiber destruction in tumor solid area and normal white matter could be clearly demonstrated. Conclusion ADC value and FA value can help differentiate tumor solid area, edema and normal white matter, A map can determine the relation between tumor and normal white matter so as to offer reference to the clinical therapy.