磁共振弥散成像对脑肿瘤周水肿区的诊断价值

Diagnosis of Diffusion Weighted Imaging and inPeritumoral Edema of Brain Tumor

目的通过对85例脑肿瘤以及5例炎性病变瘤周水肿区行磁共振弥散加权成像检查,探讨瘤周水肿的DWI表现在脑肿瘤诊断方面的临床应用价值。方法对脑肿瘤进行常规MRI序列扫描和DWI检查,均经手术和病理证实。对照分析病变的实质部分、周围水肿区以及正常脑组织的ADC值。全部数据经过SPSS(12.0)统计分析软件处理,各区域的瘤间差异用方差分析。统计结果均以-x±s表示,P<0.05为显著性意义。结果高级别胶质瘤与低级别胶质瘤、转移瘤、脑膜瘤、炎性病变之间的近侧瘤(灶)周水肿ADC值存在差异(P<0.05)。高级别胶质瘤的近侧瘤周水肿区ADC值低于远侧(P<0.05),且近侧瘤周水肿区ADC值与瘤体接近(P>0.05);低级别胶质瘤瘤体与近、远侧瘤周水肿的ADC均不能区分(P>0.05);脑膜瘤、炎性病变近侧瘤周水肿区ADC值高于远侧(P<0.05)。结论近侧瘤周水肿区ADC值可用于高级别胶质瘤与转移瘤、脑膜瘤及炎性病变之间的鉴别诊断,瘤周水肿区ADC值可用于胶质瘤分级的鉴别诊断。

Objective To evaluate the potential of DWI in diagnosing of brain tumors and defining the tumor boundary by analysing thepammeters obtained from peritumoral edema.Methods Ninty patients with brain diseases underwent routine, diffusionweighted imaging. Comparisons of apparent diffusion eoeffieients（ADC）, were done among normal, peritumoral edematous and tumoral tissues. The peritumoral signal abnommality was divided into two regions to allow investigation of whether ADC and metabolic ratios varies with distance of from the enhancing portion of the tumor, intraeranial diseases were compared by using the ANOVA. All the statistical data were displayed as x ± s, a P value of less than 0.05 indicated a statistically significant difference. Results ADC of immediate perifocal edema were prominentiy significant for differentiating high-grade gliomas from low-grade gliomas, metastases, meningiomas and inflammation（ P 〈 0.05）, As for high-grade glioma, the ADC of immediate peritumoral edema was lower than that of distant edema （ P 〈 0.05）, and the former is similar to the contrast- enhancing portion （ P 〉 0.05）. The ADC in immediate, distant peritumoral edema and solid portion of low-grade glioma could not distinguish from each other（ P 〉 0.05） .The ADC of immediate peripheral edema in patients witil meningioma or inflarmmatory disease differed significantly from those of distant peripheral edema（ P 〈 0.05）. Conclusion The ADC in immediate perifocal edema enable distinction high-grade glioma from metastasis, meningioma and inflammatory disease. The ADCof immediate peritumoral edema was helpful to grade diagnosis of glioma.