MR FLAIR序列在鉴别高级别胶质瘤与脑单发转移瘤中的价值

The Diagnostic Utility of MR Fluid Attenuated Inversion Recovery Pulse Sequence in the Differential Diagnosis Between High Grade Glioma and Solitary Metastasis

目的探讨MR液体衰减反转恢复序列（FLAIR）图像上强化边缘外邻近皮层异常信号在鉴别高级别胶质瘤和单发转移瘤中的作用和价值；评价此征象对高、中、低3个年资的神经放射科医师诊断胶质瘤的作用和价值。资料与方法对42例高级别胶质瘤和12例脑单发转移瘤患者做MRI时加扫FLAIR序列。42例高级别胶质瘤中，男28例，女14例，年龄15～76岁，平均48．8岁。13例单发转移瘤中，男7例，女6例，年龄37—73岁，平均57．6岁。分析上述病例的FLAIR及T2WI图像上强化边缘外邻近皮层异常信号征象，进行X。检验，并在高、中、低3个年资各两名神经放射科医师前后两次读片后进行接受者操作特性（ROC）曲线分析，并应用Z检验对前、后两次ROC曲线下面积进行差异性检验。结果29例的FLAIR图像上存在强化边缘外邻近皮层异常信号，胶质瘤27例，转移瘤2例，这一征象在高级别胶质瘤组和单发转移瘤组显示的差异具有统计学意义（P=0．002〈0．05）。T2WI强化边缘外邻近皮层异常信号征象在胶质瘤组和转移瘤组显示的差异亦具有统计学意义（P=0．003〈0．05）。前后两次阅片的总体ROC曲线、每一年资及每位医师前后两次阅片的ROC曲线下面积的差异均无统计学意义（P〉0．05）。五名医师的胶质瘤诊断准确率均有所提高，以低年资为著。结论FLAIR强化边缘外邻近皮层异常信号有助于高级别胶质瘤和转移瘤的鉴别诊断。在无FLAIR图像的情况下，T2WI可作为显示此征象的替代方法。

Objective To investigate the value of fluid attenuated inversion recovery （FLAIR） in distinguishing high grade glioma from solitary metastasis by evaluating nonenhancing adjacent cortical abnormal signal intensity in brain tumors, and to judge whether the sign can improve the diagnostic accuracy of glioma in different grades of neuroradiologists or not. Materials and Methods MR imaging studies with axial FLAIR of 42 patients （28 male and 14 female, age ranging from 15 -76 years old,mean age 48. 8 years old） with pathological confirmed high grade glioma and 13 solitary metastasis（7 male and 6 female, age ranging from 37 -73 years old, mean age 57.6 years old） were reviewed. Adjacent cortical involve- ment without enhancement was evaluated by combination of axial FLAIR and T2W images. Chi square test was made. The images of all cases were reviewed independently by 6 neuroradiologists in three different grades twice, and receiver operating characteristic （ROC） and Z test were conducted twice. Results Among 55 lesions, nonenhancing adjacent cortical abnor- mal signal intensity on FLAIR were seen in 29 cases ,27 were high grade glioma and 2 were solitary metastasis ,which dem- onstrated a statistically significant difference（ P 〈 0.05 ） between the two groups. The dfferent of the sige on T2WI was also remarkably statistical signiticant between the two graps. ROC analysis showed that there were no significant difference （P 〉 0.05） between different film reading time in three different grades of neuroradiologists. Diagnostic accuracy of glioma was improved more or less in the second film reading after combining the sign of nonenhancing adjacent cortical abnormal signal intensity on FLAIR with signs on T2 W in 5 doctors, among whom the accuracy was increased dramatically in the low grade doctor. Conclusion Noenhancing adjacent cortical abnormal signal intensity on FLAIR can be useful for differential diagsigns on T2WI can also be available.