DWI与SWI在脑胶质瘤分级评估中的应用研究

发布时间：2018-06-19 11:50

本文选题：胶质瘤 + 弥散加权成像　；参考：《大连医科大学》2017年硕士论文

【摘要】：目的:探讨弥散加权图像(diffusion weighted imaging,DWI)和磁敏感加权成像(susceptibility weighted imaging,SWI)对脑高、低级别胶质瘤的鉴别诊断价值。材料与方法:本实验采用回顾性研究,分析经病理证实的不同级别脑胶质瘤20例。根据2007年WHO中枢神经系统肿瘤分类标准,将患者分为高、低级别组2组,每组各10人。所有患者均应用Siemens Magnetom Trio A Tim 3.0T MR行常规MRI平扫,DWI、SWI扫描及MRI增强扫描检查。结合常规MRI图像确定肿瘤实质部分。(1)分别测量三种b值(b=1000、2000、3000s/mm2)ADC图肿瘤实质部分及对侧对应部位脑实质的最小ADC值(ADCmin)的平均值。(2)将肿瘤实质部分ADCmin除以对侧相对应脑实质ADCmin,即作rADCmin。(3)ADC参数值的差异采用独立样本t检验和秩和检验分析,并绘制ROC曲线分析各参数诊断效能。(4)采用独立样本t检验分析高、低级别组肿瘤ITSS评分是否具有统计学差异。对胶质瘤的ITSS评分与其组织病理学分级对照的相关性采用Spearman相关法检验,并绘制ROC曲线分析各参数诊断效能。(5)分析联合DWI和SWI两种技术,检出高级别胶质瘤的敏感性、特异性。结果:(1)随着b值得升高,大多数高级别胶质瘤DWI显示病灶均表现为高信号,而大部分低级别胶质瘤DWI图像显示病灶信号减低,表现为等、低信号。(2)在三种b值条件下,胶质瘤的级别与ADCmin、rADCmin值之间均呈明显负相关性,并且高b值时(rADCmin3000,r=-0.8172,P0.0001)相关性最大。(3)b值相同时,ADCmin值、rADCmin值随胶质瘤级别升高而减低,并且在b=3000s/mm2时,ADCmin值差异最大。(4)无论高、低级别组,三种b值ADCmin两两之间比较差异均有统计学意义(P0.05)。三种b值rADCmin两两之间比较差异均无统计学意义(P0.05)。(5)b=3000s/mm2时,rADCmin的诊断效能最大。(6)不同级别组胶质瘤的ITSS评分之间差异具有显著性(t=8.497,P=0.000),且两者呈高度正相关(r=0.8947,P0.001)。当把ITSS评分阈值设定为1时,高级胶质瘤诊断的敏感度、特异度分别为90.91%、88.89%。(7)两指标联合筛检敏感性、特异性分别100%、90%,较各指标单独检查的效能均高。结论:(1)DWI量化参数ADCmin值、rADCmin值在高、低级别胶质瘤中差异具有显著性,有助于脑胶质瘤分级,其中以rADCmin值(b=3000s/mm2)的对胶质瘤分级诊断意义最大。(2)SWI对胶质瘤分级诊断意义重大,其ITSS评分与胶质瘤病理分级呈高度正相关(3)DWI与SWI作为临床常用功能磁共振技术,将两者联合应用,可以提高对脑胶质瘤分级诊断效能,是常规MRI的重要补充。
[Abstract]:Objective: to investigate the value of diffusion weighted imaging (DWI) and magnetic sensitive weighted imaging (MRI) in differential diagnosis of high and low grade gliomas. Materials and methods: 20 cases of gliomas with different grades proved by pathology were analyzed retrospectively. According to WHO classification criteria of central nervous system tumors in 2007, the patients were divided into two groups: high grade group and low grade group with 10 persons in each group. All patients were examined with Siemens Magnetom Trio A Tim 3.0T Mr. Combined with conventional MRI imaging to determine the tumor parenchyma. 1) to measure the mean value of the minimum ADC value of the tumor parenchyma and the brain parenchyma in the contralateral brain parenchyma and the contralateral brain parenchyma by measuring the mean value of ADCmin of the tumor parenchyma divided by the contralateral corresponding brain solid brain respectively. The difference of ADC parameters was analyzed by independent sample t test and rank sum test. The diagnostic efficacy of each parameter was analyzed by ROC curve. 4) the ITSS score of tumor in the low grade group was statistically different from that in the low grade group. The correlation between ITSS score and histopathological grade of glioma was examined by Spearman correlation method, and the diagnostic efficacy of ROC curve was plotted. The sensitivity and specificity of high grade glioma were detected by DWI and SWI. Results with the increase of b value, most high-grade gliomas showed high signal intensity on DWI, while most low-grade gliomas showed low signal intensity on DWI images. There was a significant negative correlation between the grade of glioma and the value of rADCmin in gliomas, and the highest correlation was found between the grade of glioma and the value of rADCmin3000r-0.8172P0.0001 at high b value. The value of rADCmin decreased with the increase of grade of glioma at the same value, and the difference of the value of ADCmin at b=3000s/mm2 was the biggest. 4) in the group of high and low grade, the value of rADCmin decreased with the increase of grade of glioma. The difference of ADCmin between the three groups was statistically significant (P 0.05). There was no significant difference between the three groups of b value rADCmin. There was no significant difference in the ITSS score of rADCmin between the three groups. There was a significant difference between the ITSS scores of different grades of gliomas at the time of 3000s / mm2), and there was a highly positive correlation between the two groups. When the threshold value of ITSS was set to 1, the sensitivity and specificity of the diagnosis of advanced glioma were 90.91 and 88.89.7respectively, and the specificity was 100 ~ 90, which was higher than that of each index alone. Conclusion the difference of ADCmin value and rADCmin value in high and low grade gliomas is significant, and it is helpful to grade gliomas. The value of rADCmin is the most significant in the diagnosis of glioma grading. The ITSS score is highly positively correlated with the pathological grade of gliomas. As a common functional magnetic resonance imaging technique, the combination of ITSS and SWI can improve the diagnostic efficacy of glioma grading and is an important supplement to conventional MRI.
【学位授予单位】：大连医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R445.2;R739.41

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