Lohan Derek G, Saleh Roya, Tomasian Anderanik, Krishnam Mayil, Finn J Paul
Department of Radiology, David Geffen School of Medicine at the University of California, Los angeles, CA 90095-7206, USA.
Top Magn Reson Imaging. 2008 Feb;19(1):3-13. doi: 10.1097/RMR.0b013e31817d551f.
Continued advances in radiofrequency hardware and tailored software have, in recent times, greatly increased the power and performance of magnetic resonance imaging for noninvasive evaluation of cardiovascular diseases. Magnetic resonance imaging can uniquely be manipulated to trade temporal resolution and spatial resolution against each other, depending on whether detailed structural or functional information is required. However, to date, a number of cardiovascular magnetic resonance applications have been somewhat limited due to signal-to-noise ratio constraints, reflecting the narrow imaging window imposed by physiological cardiac motion. By increasing the operating field strength from 1.5 to 3 T, it is possible (in principle) to double the signal-to-noise ratio, which in turn may be "traded" for improvements in spatial resolution, coverage, or imaging speed. In this context, the development of parallel imaging has set the stage for impressive performance improvements in contrast-enhanced magnetic resonance angiography at 3 T. Indeed, one could argue that without parallel acquisition, the bang for the buck in going from 1.5 to 3 T would be limited. In this paper, we discuss the current status of 3-T magnetic resonance imaging for cardiovascular imaging, considering the relative gains and limitations relative to 1.5 T.
近年来,射频硬件和定制软件的不断进步极大地提高了磁共振成像在心血管疾病无创评估方面的能力和性能。根据是否需要详细的结构或功能信息,磁共振成像可以独特地进行操作,以在时间分辨率和空间分辨率之间进行权衡。然而,迄今为止,由于信噪比的限制,一些心血管磁共振应用在一定程度上受到了限制,这反映了生理心脏运动所施加的狭窄成像窗口。通过将操作场强从1.5 T提高到3 T,(原则上)有可能将信噪比提高一倍,进而可以将其“用于”提高空间分辨率、覆盖范围或成像速度。在这种情况下,并行成像的发展为3 T对比增强磁共振血管造影的性能提升奠定了基础。事实上,可以说如果没有并行采集,从1.5 T提升到3 T所带来的性价比将是有限的。在本文中,我们将讨论3 T磁共振成像在心血管成像方面的现状,同时考虑相对于1.5 T的相对优势和局限性。