单指数及双指数模型DWI在肺孤立性病变诊断效能的对比研究  

Comparison of Bi-exponential and Mono-Exponential Model of Diffusion Weighted Imaging in Evaluation of Solitary Pulmonary Lesions

作　　者：万齐[1] 李新春[1] 郑晓涛[1] 俞家熙[1] 邹乔[1] 邓颖诗[1] 余煜栋 包盈莹 雷强[1] 

机构地区：[1]广州医科大学附属第一医院放射科,510120

出　　处：《临床放射学杂志》2017年第10期1424-1428,共5页Journal of Clinical Radiology

基　　金：国家自然基金青年项目(编号:81601457);广东省医学科研基金项目(编号:A2016410);广州市科技计划项目(编号:201510010234);广州市医药卫生科技项目(编号:20151A011066)

摘　　要：目的对肺孤立性病变(SPLs)进行常规扩散加权成像(DWI)、体素内不相干运动扩散加权成像(IVIMDWI),明确单指数及双指数模型DWI在良恶性SPLs的诊断效能。方法前瞻性搜集经病理证实的62例SPLs(恶性肿瘤51例;良性病变11例),术前均行MRI平扫、DWI及IVIM-DWI。DWI扫描b值=0、600 s/mm^2,IVIMDWI采取13个b值(0、5、10、15、20、25、50、80、150、300、500、800、1000 s/mm^2)。应用受试者操作特征(ROC)曲线分析ADC、D、D~*及f值诊断效能。结果 51例恶性肿瘤D值为(0.92±0.20)×10-3mm^2/s,11例良性病变D值为(1.39±0.36)×10^(-3)mm^2/s,两者差异有统计学意义(P=0.001);恶性肿瘤f值为(16.02±8.7)%,良性病变f值为(20.72±8.75)%,两者差异无统计学意义(P=0.315);恶性肿瘤D~*值为(11.04±5.75)×10^(-3)mm^2/s,良性病变D*值为(9.79±5.27)×10^(-3)mm^2/s,两者差异无统计学意义(P=0.467)。应用ROC曲线进行分析,得出D值的曲线下面积为0.858,ADC b=600 s/mm^2曲线下面积为0.802;D值鉴别良恶性病变的最佳阈值为1.25×10^(-3)mm^2/s,敏感性和特异性分别为98.11%和72.73%。结论对于SPLs的鉴别,双指数模型与单指数模型DWI均有价值,其中D值的诊断价值最大。Objective To quantitatively evaluate the potential of intravoxel incoherent motion （IVIM）-derived parameters as well as apparent diffusion coefficient （ADC） in differentiating solitary pulmonary lesions.Methods A total of 62 patients with pathologically confirmed solitary pulmonary lesions （including 51 cases of malignant tumors;11 cases of benign lesions） were enrolled in this study.DWI scan with b value =0,600 s/mm2 was used to produce apparent diffusion coefficient （ADC） values.DWI scan with 13 b values （b =0,5,10,15,20,25,50,80,150,300,500,800,1000 s/mm2）was used to calculate IVIM derived parameters （[D],pseudo-diffusion coefficient [D ＊],and perfusion fraction [f]）.Diagnostic efficiency of each parameter was analyzed using receiver operating characteristic （ROC） curve.Results Diffusivity （D） of lung cancer was significantly lower than that of benign lesions （0.92 ±0.20） × 10-3mm2/s versus（1.39 ± 0.36） × 10-3 mm2/s;P =0.001）.The difference of pseudo-diffusion coefficient （D＊） and perfusion fraction （f） in the two groups is not statistically significant （P 〉 0.05）.In ROC analysis,D showed the highest area under curve （AUC） for distinguishing malignant from benign lesions,0.858,followed by ADCb =600 s/mm2,with AUC =0.802.the optimal threshold for differentiating malignant from benign lesions was 1.25 × 10-3mm2/s for D,and 1.54 × 10-3mm2/s for ADCb =600 s/mm2.Conclusion Both IVIM parameters and ADC are helpful for distinguishing malignant from benign lesions in lung.D value could have significantly greater diagnostic properties than other diffusion parameters did.

关 键 词：体素内不相干运动 扩散加权成像 肺孤立性病变 

分 类 号：R445.2[医药卫生—影像医学与核医学] R734.2[医药卫生—诊断学]