MRI增强扫描及表观扩散系数值在脑转移瘤和高级别胶质瘤鉴别诊断的价值分析

Value Analysis of Enhanced MRI Scan and Apparent Diffusion Coefficient in Differential Diagnosis of Brain Metastatic Tumor and High-Grade Glioma

目的探讨磁共振增强扫描及表观扩散系数(ADC)值在脑转移瘤(BM)和高级别胶质瘤(HGG)鉴别诊断的价值。方法回顾性分析本院2016年9月至2018年12月BM 28例和HGG 20例患者的临床及MRI影像资料,MRI影像评估内容包括:分类变量:肿瘤部位、数目、形态、出血、坏死囊变、瘤周水肿及强化方式,连续变量:测量瘤体大小及符合条件的瘤体实性部分、瘤周水肿区ADC值。两组中分类变量采用χ2检验或Fisher精确检验,连续变量采用独立样本t检验,有统计学意义的变量绘制受试者工作特征(ROC)曲线并评估在两组中的鉴别效能。结果BM 28例共计87个瘤灶,单发7例,双发或多发21例;HGG 20例共计22个瘤灶(2例2个瘤灶)。两组患者的临床资料中,性别、年龄和临床神经症状差异均无统计学意义(P>0.05)。两组MRI检查的分类变量中,肿瘤数目、形态、出血、坏死囊变、瘤周水肿及强化方式差异均具有统计学意义(P<0.05),而肿瘤的位置无统计学意义(P>0.05)。连续变量中瘤体实性部分ADC值差异无统计学意义(P>0.05),瘤体的大小和瘤周水肿区ADC值差异具有统计学意义(P<0.05),ROC曲线分析显示当瘤周水肿ADC值>1.38×10-3mm2/s,曲线下面积(AUC)、敏感度、特异度分别是0.878、75.0%、90.5%,当肿瘤最大径和最小径分别小于2.85 cm和2.45 cm,AUC分别是0.862、0.810,敏感度分别是81.8%、81.8%,特异度分别是81.6%、73.6%。结论MRI增强扫描能明确颅内肿瘤数目、形态和大小,结合瘤周水肿ADC值对于BM与HGG的鉴别诊断具有临床实用价值。

Objective To evaluate the value of enhanced magnetic resonance imaging(MRI)scanning and apparent diffusion coefficient(ADC)in differential diagnosis of brain metastatic tumors and high-grade gliomas.Methods The clinical and MRI imaging data of 28 patients with brain metastatic tumor and 20 patients with high-grade glioma who were treated in our hospital from September 2016 to December 2018 were retrospectively analyzed.MRI image evaluation included classification variables and continuous variables.The former consists of tumor site,number,morphology,hemorrhage,necrotic cystic change,peritumoral edema and enhancement.The latter consists of the tumor size,the ADC values of the solid part of the tumor and the area od perilesional edema.In the two groups,classification variables were evaluated by chi-square test or fisher exact test and continuous variables were evaluated by independent sample t-test.We used receiver operating characteristics curve(ROC)to describe statistically significant variables and to evaluate the discriminative efficacy between the two groups.Results There were 87 lesions in 28 cases of brain metastases comprising of 7 solitary cases and 21 double or multiple cases.A total of 22 tumor foci were detected in 20 cases of high-grade glioma(2 tumor foci in two cases).There was no statistically significant difference in gender,age and clinical neurological symptoms between the two groups(P>0.05).As for the classification variables of the MRI,there were statistically significant differences in the number,morphology,bleeding,necrotic cystic changes,peritumoral edema and enhancement mode between the two groups(P<0.05),however,the tumor location had not statistically significant differences(P>0.05).For continuous variables,there was no statistically significant difference in the ADC values of the solid components of the tumor(P>0.05),but the differences between the size of the tumor and the ADC value in the area of edema were statistically significant(P<0.05).ROC showed that when the ADC value of peritumoral edema was>1.38×10-3mm2/s,the area under the curve,sensitivity and specificity were 0.878,75.0%and 90.5%respectively.While the maximum diameter and the minimum diameter of the tumor were<2.85 cm and 2.45 cm,the area under the curve was 0.862,0.810,and sensitivity was 81.8%and 81.8%whereas specificity was 81.6%and 73.6%,respectively.Conclusion Enhanced MRI scan can determine the number,shape and size of intracranial tumors.In combination with the ADC value of the peritumoral edema;it has practical clinical value for the differential diagnosis of brain metastatic tumors and high-grade gliomas.