高级别星形细胞肿瘤与脑转移瘤瘤周区扩散张量成像

目的探讨高级别星形细胞瘤和脑转移瘤瘤周脑白质T2WI高信号区扩散张量成像（DTI）的特征性。方法星形细胞肿瘤和脑转移瘤患者各11例,比较两种肿瘤瘤周T2WI高信号区的平均弥散系数（AD）和部分各向异性（FA）。结果高级别星形细胞瘤（1.62±0.39）与脑转移瘤（1.59±0.32）的瘤周区FA值差异无统计学意义（P〉0.05）;高级别星形细胞瘤瘤周区AD值（1.19±1.15）×10^-3mm^2/s]小于脑转移瘤（1.44±0.15）×10^-3mm^2/s]。结论测量瘤周区AD值可用于鉴别高级别星形细胞瘤和单发脑转移瘤。

Diffusion tensor imaging of peritumoral areas of high-grade astrocytomas and metastatic brain tumors

Objective To investigate the diffusion tensor imaging (DTI) metrics characterizes of peritumoral hyperintense white matter areas on T2WI of high-grade astrocytomas and metastatic brain tumors. Methods Routine MRI and DTI were performed in 11 patients with high grade astrocytomas and in 11 patients with metastatic brain tumors. The average diffusion coefficient (AD) and fractional anisotropy (FA) were calculated from the ROIs placed on hyperintese regions on T2WI surrounding each tumors, respectively. Results The mean peritumoral FA of the astrocytomas (1.62±0.39),displayed no significant difference from those of metastatic lesions (1.59±0.32,P>0.05). Whereas, the mean peritumoral AD of the astrocytomas (×10^-3 mm²/s) was significantly lower than those of metastatic lesions (×10^-3 mm²/s, P <0.01). Conclusion Peritumoral AD can be used to distinguish high grade astrocytomas from solitary metastatic brain tumors.