不同b值弥散加权成像技术在肺部肿瘤MRI中的应用价值

发布时间：2018-08-22 09:49

【摘要】：目的:分析不同b值下病变的弥散加权成像技术(diffusion-weighted imaging,DWI)信号特点及其表面扩张系数(apparent diffusion coefficient,ADC),探讨其在肺部肿瘤MRI中的应用价值。方法 :收集37例CT发现并经病理或临床随访证实肺部肿块,行肺部常规MRI序列以及不同b值(500、800、1 000 s/mm2)DWI。在病灶最大径层面上,分别测量各b值下病变的DWI信号强度、ADC值;通过受试者操作特征曲线(receiver operating characteristic curve,ROC),分析最佳b值及ADC值对肺部肿块的鉴别诊断作用;分析病灶DWI信号大小、ADC值与病理类型的关系。结果:(1)肺部良性肿块DWI呈等低信号或低信号,大多数恶性肿块DWI呈现等信号或高信号。(2)良性肿块在b值为500、800、1 000 s/mm2时,ADC值分别为(2.142±0.560)×10~(-3)、(1.746±0.499)×10~(-3)、(1.457±0.374)×10~(-3)mm2/s;恶性肿块在b值为500、800、1 000 s/mm2时,ADC值分别为(1.499±0.298)×10~(-3)、(1.274±0.230)×10~(-3)、(1.179±0.176)×10~(-3)mm2/s。(3)3种b值对良恶性肿块的ADC值差异均有统计学意义(t=4.637,P0.001;t=3.695,P0.001;t=3.097,P0.004)。(4)3组b值ROC曲线下面积(AUC)分别为0.869、0.794和0.765,AUC0.5,可以作为良恶性肿块鉴别诊断的有效指标,其中以500 s/mm2时所测ADC值的曲线下面积最大,ADC值良恶性鉴别阈值取1.475×10~(-3)mm2/s时,诊断作用最高,敏感性为0.833、特异性为0.773、约登指数0.606。结论:DWI信号强度及ADC值大小对肺部肿块鉴别诊断有较高价值,肺良性和恶性病变组ADC值均随b值增加而逐渐变小。
[Abstract]:Objective: to analyze the signal characteristics of diffusion-weighted imaging (diffusion-weighted) and the surface expansion coefficient (apparent diffusion) of lesions with different b values, and to evaluate the value of diffusion-weighted imaging (DWI) in lung tumor MRI. Methods: 37 cases of lung masses confirmed by CT and confirmed by pathology or clinical follow-up were collected. Routine MRI sequences and different b values (500,800,1000 s/mm2) DWI were performed. At the maximum diameter level of the lesion, the DWI signal intensity and the value of DWI were measured under each b value, and the value of the best b value and ADC value in the differential diagnosis of pulmonary masses were analyzed by (receiver operating characteristic curved-ROC. The relationship between DWI signal size and pathological type was analyzed. Results: (1) DWI of benign lung masses showed iso-low signal intensity or low signal intensity. 澶у�氭暟鎭舵�ц偪鍧桪WI鍛堢幇绛変俊鍙锋垨楂樹俊鍙，

本文编号：2196736