摘要
目的:评价GRAPPA技术在呼吸导航磁共振冠脉成像中的应用价值。方法:对19例志愿者使用和不使用GRAPPA技术行右冠脉靶容积扫描,并使用GRAPPA技术行全心扫描。经后处理得到冠脉图像,从扫描时间、信噪比、对比噪声比、图像质量方面评价应用GRAPPA前后的图像;评价冠脉主要分支的显示情况。结果:GRAPPA技术应用前的扫描时间为(7.67±1.24)min、信躁比为35.89±4.64、对比噪声比为20.35±4.27,应用后分别为(4.65±1.25)min、29.73±4.18、16.42±3.77,三者差异有统计学意义;图像评分差别无统计学意义。靶容积扫描和全心扫描对右冠脉近中段的显示率分别为94.7%和93.3%,对右冠脉远段显示率分别为78.9%和86.7%,全心扫描对左主干及前降支、回旋支近中段显示率为93.3%,前降支及左回旋支远段为86.7%和80.0%。结论:GRAPPA技术可缩短呼吸导航磁共振冠脉成像(41±13)%的扫描时间(加速因子为2),获得良好的冠状动脉图像,应用GRAPPA技术可完成全心扫描,与靶容积扫描相比,具有更好的应用前景。
Objective：To assess the value of generalized autocalibrating partially parallel acquisition （GRAPPA） ap plied to free-breathing 3D coronary MR angiography （CMRA） with real time navigation. Methods： Nineteen healthy volunteers underwent free-breathing 3D navigator-gated CMRA,including targeted-volume CMRA for the right coronary artery （RCA） with and without GRAPPA and whole-heart CMRA with GRAPPA. Between targeted-volume CMRA with and without GRAPPA, the signal-to-noise ratio （SNR）, contrast-to-noise ratio （CNR） and acquisition time were compared using paired t test,and image quality was visually rated and compared using paired rank sum test,with P values less than 0.05 considered significant. The image quality of the major coronary arteries was also evaluated in whole-heart CMRA with GRAPPA. Results：The acquisition time,SNR,CNR were （4.65±1.25）min,29.73±4. 18 and 16.42±3.77 for sequences with GRAPPA versus （7.67±1.24）min （P〈0.05） ,35.89±4.64 （P〈0.05） and 20.35±4.27 （P〈0. 05） for sequences without GRAPPA, respectively. No significant difference was found between overall image quality of targeted-volume CMRA with and without GRAPPA （P〉0. 05）. Adequate visualizations were achieved by targeted volume sequences with GRAPPA in 94.7% of the proximal and middle RCA and 78.9% of the distal RCA. Whole-heart 3D CMRA was capable of demonstrating all major coronary arteries through single scan with adequate visualizations in 93. 3% of the proximal and middle segments and （80.0±86.7）% of the distal segments. Conclusion.. In free-breathing 313 navigator gated CMRA, it may achieve a reduction of （41±13）% in scanning time and yield fine visualizations of major coronary arteries in wholeheart 3D CMRA by using GRAPPA.
出处
《放射学实践》
2008年第8期889-893,共5页
Radiologic Practice
关键词
冠状血管成像
磁共振成像
全局自动校准部分平行采集技术
Coronary angiography
Magnetic resonance imaging
Generalized autocalibrating partially parallel acquisition
作者简介
金航（1978-），男，浙江东阳人，博士，医师，主要从事心血管MRI影像诊断工作。
通讯作者：曾蒙苏，E-mail：zms@zshospital．net
