不同分级少突胶质细胞肿瘤的MRI诊断

MRI diagnosis of different levels of oligodendrogliomas

目的探讨不同分级少突胶质细胞肿瘤的MRI表现特点,为临床治疗方法的选择提供参考。方法回顾性分析59例不同分级少突胶质细胞肿瘤的MRI表现,并和病理结果对照分析。结果本组不同分级少突胶质细胞肿瘤共59例,其中少突胶质细胞瘤(WHOⅡ级)37例,好发于额、顶叶交界区,34例边界模糊,33例T1WI呈低信号,37例T2WI呈高信号,增强扫描30例呈轻度强化,7例囊变,8例出血,5例伴瘤周水肿;间变少突胶质细胞瘤22例,好发于额、顶、颞叶交界区,21例边界较清,19例T1WI例呈低信号,T2WI呈高信号,增强扫描17例明显强化,12例囊变坏死,9例出血,22例伴瘤周水肿。结论不同分级少突胶质细胞肿瘤MRI表现有一定差异。

To explore the imaging features in two types of oligodendrogliomas and their histopathological manifestations for better clinical differential diagnosis and treatment guidance. Materials and Methods： We retrospectively examined MRI findings and their histologic correlations of total 59 oligodendroglioma cases diagnosed with both low grade and anaplastic oligodendroglial tumor. Results： There were 37 low grade （WHO U grade） and 22 anaplastic （WHO III grade） oligodendrogliomas in this study. Among 37 low grade （WHO II grade） cases, the tumor was mostly seen in gray-white matter junction of parietal lobe; 34 cases had blurred margin and 3 cases had well-demarcated margin; on Tl-weighted images, the tumor showed hypointense in 33 cases and isointense in 4 cases, on T2-weighted images, the tumor showed hyperintensities on T2-weighted images in 37 cases with mild tumoral enhancement in 30 cases and heterogeneous enhancement in 7 cases; there was other pathological changes such ascalcification （n-32）~ cystic degeneration （n=7）, hemorrhage （n=8）, peritumoral edema （n-5）. In contrast, among 22 anaplastic oligodendrogliomas （WHO III grade）, the tnmor was mostly seen in the gray-white matter junction of temporal cortex, 21 cases had clear boundary and 1 case with poorly-defined boundary, the tumor showed hypointensities on Tl-weighted images in 19 cases and isointensities in 3 cases, the tumor showed hyperintensities on T2-weighted images in 19 cases mild enhancement in 5 cases and significant enhancement in 17 cases, other pathologic findings including cystic necrosis （n=12）, hemorrhage （n=9）, and peritumoral edema （n=22）. Conclusion： We have described the MRI features such as cystic necrosis, hemorrhage, edema, and enhancement that are useful in differentiating the two types of oligodendrogliomas.