不同b值扩散加权成像在周围性肺癌的应用研究  

Application of diffusion-weighted imaging with different b values in detection of peripheral lung cancer

作　　者：王波[1] 杨清华[1] 刘卫军[1] 刘洪芳[1] 王穗春[1] 张鑫颖[1] 

机构地区：[1]广东药学院附属第一医院放射科,广州市510080

出　　处：《实用医学杂志》2012年第18期3031-3034,共4页The Journal of Practical Medicine

基　　金：广东省卫生厅立项科研基金资助课题(编号:A2009336)

摘　　要：目的:评价不同b值磁共振背景抑制扩散加权成像(DWIBS)对周围性肺癌病灶的检出效果。方法:48例患者接受了DWIBS成像,b值分别采用400、600、800s/mm2进行扫描,比较各b值组的信噪比SNR、对比噪声比CNR和ADC图上能显示病灶并能测量ADC值的能力。结果:成像质量比较,b400的SNR和CNR均为最高,不同b值组间SNR差异有统计学意义(P=0.0000),但CNR中b400与b600差异没有显著性(P>0.05)。不同b值其ADC图上显示病灶能力与病灶大小有关,b值选择对病灶的显示有一定影响:病灶最大径<0.5cm者,3个b值取值ADC图均未能显示病灶;0.5～1.0cm病灶,部分显示模糊或不显示,犹以b800为甚,b400与b600之间无明显差异(P>0.05);>1cm的病灶,3种b值的ADC图绝大部分能显示,b400的效果稍好,但三者之间差异无显著性(P=0.1681)。结论:在T2WI基础上加做b值为600s/mm2的DWIBS,可以兼顾真实的ADC值、图像质量以及ADC图显示病灶能力等方面,以获得相对较好的周围性肺癌性病变的DWIBS影像。Objective To evaluate the effects of different b values in diffusion weighted imaging with background suppression （DWIBS） on detection of peripheral lung cancer. Methods Forty-eight patients received DWIBS using b values of 400 s/ram2, 600 s/mm2 and 800 s/mm2 for scanning in order to compare signal-to-noise ratio （SNR）, apparent contrast -tonoise ratio （CNR） and the ability to reveal foci on apparent diffusion coefficient （ADC） map and measure ADC value between b-value groups. Results When the imaging quality was compared, h400 group had the highest SNR and CNR; the difference in SNR between different b-value groups had statistical significance （P = 0.000 0）, except for the lack of significant difference in CNR between b400 and,b600 （P 〉 0.05 ）. The focus-revealing capability on ADC map with different b values was correlated with the size of lesions and selection of b values affected the ability to reveal foci ： for lesions with diameter 〈 0.5 cm, no foci could he revealed on ADC map for all the 3 b values; for lesions with diameter within 0.5 cm ～ l.0 cm, only fuzzy partial revelation or absence of loci was obtained, especially with b800, and the difference between b400 and b600 was insignificant （P 〉 0.05） ; for lesions with diameter 〉 1 cm, majority of foci could be revealed on ADC map for all 3 b values, with slightly better quality obtained with h400, although there was no statistically significant difference among the 3 groups （P = O. 168 1 ）. Conclusion Application of DWIBS with 600 s/mm2 b value on basis of T2WI is able to balance the actual ADC value, image quality, focus-revealing capability of ADC map and related aspects in order to obtain better quality DWIBS of peripheral lung cancerous lesions.

关 键 词：磁共振成像 背景抑制扩散加权成像 B值 ADC值 周围性肺癌 

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]