摘要
目的:探讨1.5TDWI对肺内良、恶性病变的鉴别诊断价值及b值的优化。方法:搜集40例经病理/临床证实的肺内良、恶性病变患者(恶性病变23例,良性病变17例)的影像及临床资料,40例均经MSCT检查发现肺部病变,并行常规T1WI、T2WI以及多b值DWI(b=0,300,600,1000s/mm2)检查,测量3组b值测得的ADC值,分析不同b值对图像质量、信噪比(SNR)、对比噪声比(CNR)的影响,根据受试者工作特征(ROC)曲线评价不同b值下ADC值鉴别肺部良、恶性病变的诊断效能;并比较同一b值下良、恶性病变ADC值的差异。结果:随着b值的增加,DWI图像信号逐渐增高,ADC、SNR及CNR值逐渐下降;b值为300和600s/mm2两组图像SNR值差异无统计学意义(P>0.05),b值为300与1000s/mm2以及600与1000s/mm2两组SNR值差异均具有统计学意义(P均<0.05);CNR值在两两组间的差异均具有统计学意义(P均<0.05)。b值为300、600和1000s/mm2时,ROC的曲线下面积(AUC)分别为0.78、0.83和0.81,且均具有诊断意义(AUC均>0.5),当b=600s/mm2时,诊断效能最高。在同一b值下,恶性病变图像信号高于良性病变,且ADC值低于良性病变(P均<0.05)。结论:1.5T DWI多b值胸部扫描有助于鉴别肺内良、恶性病变,当b=600s/mm2时,对肺良、恶性病变的鉴别诊断效能最高。
Objective：To investigate the value of diffusion-weighted imaging using 1. 5T MR scanner in identifying benign and malignant lung lesions and optimization of the b-value. Methods：40 cases with pulmonary lesions found in MSCT examination were collected, consisting of 23 malignant cases and 17 benign cases. All patients underwent conventional T1WI, T2 WI and DWI with multi-b-value. ADC values were measured and analysed, as well as the impacts of b-value on imaging quality,signal-to-noise ratio （SNR） and contrast-to-noise ratio （CNR）. According to the receiver operating characteristic （ROC） curve, the diagnostic efficiency of identifying benign and malignant lung lesions with ADC value under various b values was ascertained. ADC values of benign and malignant lesions at the same b-value were compared. Results：On the DWI of lung lesions with various b values, the signal intensity of images gradually increased and the ADC values gradully reduced with the increasing b values. The signal-to-noise ratio （SNR） and contrast-to-noise ratio （CNR） gradully reduced （P〉0.05 of SNR when b= 300 and 600s/mm^2）. The AUC with various b values were 0.78, 0. 83,0.81, respectively. The diagnostic efficiency was the highest when the b-value was 600s/mm^2. With the same b-value, the mean ADC value of malignant lesions was lower than that of benign lesions （All P〈0.05）. Conclusion：Chest scanning with 1.5T DWI can be used to distinguish benign and malignant pulmonary lesions with various b values （300,600 and 1000s/mm^2 ）. The diagnostic efficiency is the highest when b-value was 600s/mm^2.
出处
《放射学实践》
北大核心
2015年第2期141-144,共4页
Radiologic Practice
基金
辽宁省自然科学基金资助项目(201302/035)
关键词
肺疾病
扩散加权成像
诊断
鉴别
表观扩散系数
信噪比
Lung diseases
Diffusion-weighted imaging
Diagnosis,differential
Apparent diffusion coefficient
Signal-to-noise ratio
