Foo T K, Saranathan M, Hardy C J, Ho V B
Applied Science Laboratory, GE Medical Systems, Milwaukee, Wisconsin, USA.
Top Magn Reson Imaging. 2000 Dec;11(6):406-16. doi: 10.1097/00002142-200012000-00009.
Coronary artery magnetic resonance imaging strategies have tended to focus on the use of a single method performed during either breath-holding or free-breathing for all patients. However, significant variations exist among patients in terms of breath-holding ability and respiratory regularity that make the use of a single technique alone not universally successful. Therefore, it is prudent to make available a number of magnetic resonance imaging methods such that an appropriate respiratory motion reduction strategy can be tailored to suit the patient's respiratory pattern and characteristics. A tailored approach that can draw on different image acquisition techniques for coronary artery imaging is presented. A decision tree is proposed to triage patients into imaging regimes with the greatest probability of success, according to the patient's ability to breath-hold or exhibit steady respiration. Methods include volume free-breathing acquisitions using navigator echoes for respiratory monitoring in the 8- to 10-min scan time range, two-dimensional spiral navigators (2- to 3-min scan time), breath-held multislice and vessel-tracking spirals (16- to 20-second scan time), and real-time imaging approaches incorporating adaptive signal averaging. The development of multiple acquisition strategies substantially improves the opportunities to generate high-quality, diagnostic images of the coronary arteries.
冠状动脉磁共振成像策略往往侧重于对所有患者采用在屏气或自由呼吸期间执行的单一方法。然而,患者在屏气能力和呼吸规律性方面存在显著差异,这使得单独使用单一技术并非普遍成功。因此,明智的做法是提供多种磁共振成像方法,以便能够根据患者的呼吸模式和特征量身定制合适的呼吸运动减少策略。本文介绍了一种可利用不同图像采集技术进行冠状动脉成像的定制方法。提出了一种决策树,根据患者的屏气能力或稳定呼吸能力,将患者分类到最有可能成功的成像方案中。方法包括在8至10分钟扫描时间范围内使用导航回波进行呼吸监测的容积自由呼吸采集、二维螺旋导航器(2至3分钟扫描时间)、屏气多层和血管追踪螺旋扫描(16至20秒扫描时间)以及结合自适应信号平均的实时成像方法。多种采集策略的发展大大增加了生成高质量冠状动脉诊断图像的机会。