MRI定量参数鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别

目的 观察MRI定量参数鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别的价值。方法 回顾性分析经病理确诊或随访复查诊断的58例丘脑胶质瘤（高、低级别胶质瘤分别为21例及37例）及21例丘脑转移癌患者，均接受头部常规MR检查，其中20例高级别胶质瘤、28例低级别胶质瘤及5例转移癌接受¹H-MR波谱（MRS）检查。比较高、低级别胶质瘤及转移癌之间水肿指数（EI）、对比增强率（CER）的差异，以及高、低级别胶质瘤间代谢物比值的差异。针对单因素分析结果显示差异有统计学意义的定量参数绘制受试者工作特征（ROC）曲线，计算曲线下面积（AUC），评估其鉴别丘脑胶质瘤与转移癌及评估胶质瘤级别的效能。结果 丘脑转移癌EI大于高、低级别胶质瘤（P均<0.05）；高级别胶质瘤及转移癌CER均大于低级别胶质瘤（P均<0.05）。丘脑高级别胶质瘤实质区胆碱复合物（Cho）/肌酸（Cr）高于低级别胶质瘤（P=0.01）。高、低级别胶质瘤及转移癌之间，其余定量参数差异均无统计学意义（P均>0.05）。EI鉴别丘脑转移癌与胶质瘤的AUC为0.656，CER及肿瘤实质区Cho/Cr鉴别高级别与低级别胶质瘤的AUC分别为0.801及0.775。结论 EI有助于鉴别丘脑胶质瘤与转移癌；CER及肿瘤实质区Cho/Cr可用于鉴别丘脑高、低级别胶质瘤。

MRI quantitative parameters for differentiating glioma from metastasis in thalamus and assessing grade of glioma

Objective To explore the value of MRI quantitative parameters for differentiating glioma from metastasis in thalamus and assessing grade of glioma. Methods Data of 58 patients with thalamic gliomas (21 high-grade and 37 low-grade gliomas) and 21 with thalamic metastases confirmed pathologically or with following-up were retrospectively analyzed. All patients underwent routine head MR examination, among them 20 with high-grade glioma, 28 with low-grade glioma and 5 with metastases underwent ¹H-MR spectroscopy (MRS) examination. The edema index (EI) and contrast enhancement rate (CER) were compared among high- and low- grade glioma and metastases, while the metabolite ratios were compared between high- and low- grade gliomas. Then receiver operating characteristic (ROC) curves of MRI quantitative parameters being significant different among high- and low- grade glioma and metastases were drawn, and the area under the curves (AUC) were calculated to evaluate the efficacy for differentiating high- and low- grade glioma from metastases in thalamus. Results EI of thalamic metastases was higher than that of high- and low-grade glioma (both P<0.05). CER of high-grade glioma and metastases were both higher than that of low-grade glioma (both P<0.05). Choline (Cho)/creatine (Cr) in parenchyma of high-grade glioma was higher than that of low-grade glioma (P=0.01). No significant difference of the other quantitative parameters was found among high-, low-grade gliomas and metastases (all P>0.05). AUC of EI for distinguishing thalamic metastases and glioma was 0.656, of CER and Cho/Cr of parenchyma for distinguishing high-grade and low-grade glioma was 0.801 and 0.775, respectively. Conclusion EI was helpful for differentiating thalamic glioma from metastasis. CER and Cho/Cr of parenchyma could be used for differentiating high- and low-grade gliomas in thalamus.