Feuerlein Sebastian, Klass Oliver, Pasquarelli Alberto, Brambs Hans-Juergen, Wunderlich Arthur, Duerk Jeffrey L, Aschoff Andrik J, Hoffmann Martin H K
Department of Diagnostic and Interventional Radiology, University of Ulm, Steinhoevelstrasse 9, 89075 Ulm, Germany.
Acad Radiol. 2009 Mar;16(3):374-9. doi: 10.1016/j.acra.2008.08.015.
The aim of this study was to investigate whether a respiratory biofeedback system could increase navigator efficiency and maintain image quality compared to conventional respiratory-gated magnetic resonance coronary angiography (MRCA).
Eighteen healthy volunteers underwent MRCA using three different respiratory-gating protocols. A conventional expiratory free-breathing (FB) sequence was compared to two approaches using navigator echo biofeedback (NEB), a midinspiratory approach (NEBin) and an expiratory approach (NEBex). Navigator data reflecting the position of the diaphragm relative to a 3-mm gating window were made available to the subject using a video projector in combination with a Plexiglas screen and mirror goggles. Image quality was graded by two radiologists in consensus using a visual score ranging from 1 (not visible) to 4 (excellent vessel depiction).
The NEB approaches improved navigator efficiency (71.1% with NEBex and 68.0% with NEBin vs 42.2% with FB), thus reducing total imaging time. This difference was statistically significant (P(NEBin)=.007; P(NEBex)=.001). Image quality in the NEBex group was comparable to that in the FB group (median score, 2.44 vs 2.52), but it proved to be significantly lower (median score, 1.94 vs 2.52) for the right coronary artery and the left anterior descending coronary artery in the NEBin group.
NEB maintains image quality and significantly increases navigator efficiency, thereby decreasing total imaging time by about 40% compared to a conventional FB acquisition strategy.
本研究旨在探讨与传统呼吸门控磁共振冠状动脉造影（MRCA）相比，呼吸生物反馈系统是否能提高导航效率并保持图像质量。
18名健康志愿者采用三种不同的呼吸门控方案进行MRCA检查。将传统的呼气自由呼吸（FB）序列与两种使用导航回波生物反馈（NEB）的方法进行比较，即吸气中期方法（NEBin）和呼气方法（NEBex）。通过视频投影仪结合有机玻璃屏幕和护目镜，向受试者提供反映膈肌相对于3毫米门控窗口位置的导航数据。由两名放射科医生共同使用从1（不可见）到4（血管显示极佳）的视觉评分对图像质量进行分级。
NEB方法提高了导航效率（NEBex为71.1%，NEBin为68.0%，而FB为42.2%），从而缩短了总成像时间。这种差异具有统计学意义（P（NEBin）=0.007；P（NEBex）=0.001）。NEBex组的图像质量与FB组相当（中位数评分，2.44对2.52），但NEBin组右冠状动脉和左前降支冠状动脉的图像质量明显较低（中位数评分，1.94对2.52）。
NEB可保持图像质量并显著提高导航效率，从而与传统的FB采集策略相比，将总成像时间减少约40%。
