摘要
目的:应用1.5T磁共振比较研究导航触发与自由呼吸在多b值DWI肝脏成像的特点。方法:应用1.5T磁共振,对30例临床诊断肝局灶性病变的病人同时使用导航触发、自由呼吸多b值扩散加权扫描成像,评估两组肝脏图像质量和成像时间长短,测量和比较两组不同b值图像的信号强度、肝脏信噪比及ADC值。结果:导航触发与自由呼吸序列图像评分分别为3.57±0.56,3.74±0.52,差异无统计学意义(P>0.05);导航触发扫描时间长于自由呼吸序列,分别为434±21s,130s(P<0.01);导航触发序列肝实质SNR(50,400,800)为57.49±20.67,39.84±15.41;27.38±8.60,高于自由呼吸序列SNR(50,400,800)=41.56±15.03,29.26±9.44,22.84±6.85(P<0.01)。两者肝实质ADC无差异(P>0.05),分别为1.130±0.098,1.086±0.072。结论:对于多b值肝脏扩散加权成像,导航触发较自由呼吸技术图像信噪比高,自由呼吸技术成像时间相对短,两种技术所测量肝脏ADC值无明显差异。
Purpose： To compare the image characteristic of multi-b-value diffusion-weighted（DW） liver imaging with navigator-triggered（NT） technique with that with free-breathing（FB） on 1.5T MRI. Methods： Thirty patients with focal liver lesion underwent multi-b-value（b=50, 400, 800s/mm2） DW imaging with two different techniques： NT and FB. The acquisition time and image quality scores of them were assessed. The signal intensity of images at each b-value, SNR and ADC values of liver were calculated and compared between these two techniques. Results： The image quality score of images acquired with NT technique was 3.57±0.56 and equal to that with FB technique 3.74±0.52（P〉0.05）. The mean acquisition time for FB scheme was shorter than that for NT（130vs434±21s, P〈0.01）. The SNR（50,400,800） of liver parenchyma with NT acquisition was superior to that with FB（P〈0.01）. The ADC values of liver parenchyma were not with significant difference between two techniques（P〉0.05）. Conclusion： As for multi-b-value DW liver imaging, NT technique provides better SNR, whereas FB technique holds advantages of shorter acquisition time with no difference in ADC value.
出处
《中国医学计算机成像杂志》
CSCD
北大核心
2016年第2期132-137,共6页
Chinese Computed Medical Imaging
关键词
扩散加权成像
多b值
导航触发
自由呼吸
肝脏
Diffusion-weighted imaging
Multi-b-value
Navigator-triggered
Free-breathing
Liver
