磁共振DWI在判断小儿颅内肿瘤分级中的价值

目的：探讨磁共振DWI在判断小儿颅内肿瘤分级中的价值。方法：回顾性分析60例经病理证实小儿颅内肿瘤的扩散加权成像（DWI）及ADC图像,包括WHOⅠ级19例,Ⅱ级17,Ⅲ级14例,Ⅳ级10例。测量肿瘤实质部分及正常脑白质的ADC值,经统计学分析各组之间的差异。结果：肿瘤实质ADC及实质/白质值（rADC）测量,Ⅰ-Ⅳ级肿瘤的ADC值分别为（1.30±0.35）×10^-3（、1.06±0.23）×10-3、（0.91±0.15）×10^-3和（0.63±0.11）×10^-3mm^2/s,rADC分别为1.69±0.49、1.32±0.28、1.20±0.29和0.79±0.19,除Ⅱ、Ⅲ级肿瘤间不存在统计学差异外,其余各组间差异均有统计学意义。Ⅰ-Ⅱ和Ⅲ-Ⅳ级组肿瘤ADC值分别为（1.24±0.34）和（0.87±0.28）×10^-3mm^2/s,rADC分别为1.60±0.45和1.17±0.38,两组差异有统计学意义（P〈0.05）,Ⅰ-Ⅱ级组高于Ⅲ-Ⅳ级组。结论：DWI对于小儿颅内肿瘤级别的判断有一定的帮助,而ADC或rADC值,特别是后者能较为可靠地鉴别小儿常见颅内肿瘤的级别。

Value of diffusion weighted MR imaging in determining the WHO grade of intracranial tumors in children

Objective：To evaluate the diffusion weighted MR imaging（DWI） in determining the WHO grade of intracranial tumors in children.Methods：The diffusion weighted MR imaging（DWI） and apparent diffusion coefficient（ADC） value of sixty cases with pathology proved intra-cranial tumors in children including grade Ⅰ（19 cases）,grade Ⅱ（17 cases）,grade Ⅲ（14 cases） and grade Ⅳ（10 cases） tumors were retrospectively analyzed.The ADC values of solid part of tumor and the normal white matter were measured and the difference among the groups was statistically analyzed.Results：The ADC（rADC） values for grade Ⅰ~Ⅳ tumors were 1.30±0.35、1.06±0.23、0.91±0.15、0.63±0.11（1.69±0.49、1.32±0.28、1.20±0.29、0.79±0.19） respectively.Apart from grade Ⅱ and grade Ⅲ with no statistical difference,there were significant differences among the rest.The ADC（rADC） values for gradeⅠ~Ⅱ group and grade Ⅲ~Ⅳ group were 1.24±0.34、0.87±0.28（1.60±0.45、1.17±0.38） respectively with significant statistical difference（P〈0.05）.The ADC or rADC values of grade Ⅰ~Ⅱ group were higher than that of grade Ⅲ~Ⅳ group.Conclusion：DWI showed certain significance in determinating the grade of intracranial tumors in children.ADC especially rADC values are reliable in the differentiation of grade Ⅲ~Ⅳ from grade Ⅰ~Ⅱ tumors.