MR脑血流灌注成像在星形细胞肿瘤中的应用研究  

Utility of perfusion-weighted MR imaging in astrocytomas

作　　者：彭靖[1] 戴建平[1] 朱明旺[1] 李少武[1] 詹炯[1] 刘翔[1] 

机构地区：[1]北京市神经外科研究所神经影像中心

出　　处：《中华放射学杂志》2003年第7期636-639,共4页Chinese Journal of Radiology

摘　　要：目的　评价MR脑血流灌注成像在星形细胞肿瘤中的应用价值。方法　经手术及病理证实的星形细胞肿瘤共 2 6例。行常规MR及MR灌注成像检查。构建局部脑血容量 (rCBV)图 ,并计算肿瘤最大相对局部脑血容量 (rrCBV)值。评价星形细胞肿瘤的rCBV图表现 ,并分析平均最大rrCBV值与肿瘤病理学级别之间的关系。结果　 9例Ⅱ级星形细胞瘤的rCBV分布较均匀 ,接近或略高于对侧脑白质。 7例Ⅲ级和 10例Ⅳ级星形细胞肿瘤的rCBV分布明显不均匀 ,肿瘤实性区rCBV多有不同程度的升高 ;瘤内囊变坏死区和瘤周水肿区rCBV降低。增强MRI上 ,2例Ⅲ级和 2例Ⅳ级肿瘤内无明显强化区域 ,在rCBV图上脑血容量明显升高。Ⅱ～Ⅳ级肿瘤最大rrCBV的平均值分别为 0 91±0 18、3 5 1± 1 0 1和 4 75± 1 2 3;Ⅱ级与Ⅲ级 (t=6 79,P <0 0 1)、Ⅱ级与Ⅳ级 (t=9 75 ,P <0 0 1)、Ⅲ级与Ⅳ级之间 (t=2 19,P <0 0 5 )平均最大rrCBV值差异均有显著性意义。结论　MR脑血流灌注成像可观察星形细胞肿瘤的血流灌注变化 ,对判断星形细胞肿瘤的病理学分级有重要临床意义。Objective To evaluate the diagnostic value of perfusion weighted magnetic resonance imaging (PWI) in astrocytomas. Methods PWI were performed in 26 patients with histologically verified astrocytomas. Regional cerebral blood volume (rCBV) maps were calculated from dynamic MR image sets. The rCBV of lesions was expressed as a percentage of the relative rCBV of contralateral normal white matter. The maximum rrCBV of each lesion was correlated with the histopathologic grading of astrocytomas. Results Nine grade Ⅱ astrocytomas demonstrated homogeneously rCBV, equal to or higher than that of the corresponding normal white matter. While 7 grade Ⅲ and 10 grade Ⅳ astrocytomas often showed areas of both high and low rCBV. In 2 grade Ⅲ and 2 grade Ⅳ astrocytomas, the lesion demonstrated no obvious contrast enhancement on T 1-weighted images but showed large perfusion abnormalities. Mean values of maximum rrCBV in grade Ⅱ～Ⅳ astrocytomas were 0.91±0.18, 3.51±1.01, and 4.75±1.23, respectively. The maximum rrCBV of grade Ⅱ astrocytomas was significantly lower than grade Ⅲ ( t =6.79, P <0.01) and grade Ⅳ ( t =9.75, P <0.01), grade Ⅲ was lower than those of grade Ⅳ ( t =2.19, P <0.05), the differences were statistically significant. Conclusion PWI can show the hemodynamic changes of astrocytomas. It′s useful in the assessment of histopathologic grade of astrocytomas.

关 键 词：星形细胞肿瘤 磁共振成像 脑血流灌注成像 脑血容量 

分 类 号：R739.4[医药卫生—肿瘤]