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Initial results on in vivo human coronary MR angiography at 7 T

Seven tesla (T) MR imaging is potentially promising for the morphologic evaluation of coronary arteries because of the increased signal‐to‐noise ratio compared to lower field strengths, in turn allowing improved spatial resolution, improved temporal resolution, or reduced scanning times. However, there are a large number of technical challenges, including the commercial 7 T systems not being equipped with homogeneous body radiofrequency coils, conservative specific absorption rate constraints, and magnified sample‐induced amplitude of radiofrequency field inhomogeneity. In the present study, an initial attempt was made to address these challenges and to implement coronary MR angiography at 7 T. A single‐element radiofrequency transmit and receive coil was designed and a 7 T specific imaging protocol was implemented, including significant changes in scout scanning, contrast generation, and navigator geometry compared to current protocols at 3 T. With this methodology, the first human coronary MR images were successfully obtained at 7 T, with both qualitative and quantitative findings being presented. Magn Reson Med, 2009. © 2009 Wiley‐Liss, Inc.