Jing Yu1,2, Michael Schr, 23, Harsh Agarwal, 2,4, Matthias Stuber2,5
1Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States; 2Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, United States; 3Philips Healthcare, Cleveland, OH, United States; 4Department of Electrical and Computer Engineering, John Hopkins University, Baltimore, MD, United States; 5Department of Radiology, University Hospital Center and University of Lausanne (CHUV), Lausanne, VD, Switzerland
One of the challenges in coronary MRA is insufficient SNR. To improve the blood-pool SNR in prospective respiratory navigator gated whole-heart coronary MRA, radiofrequency excitations of the gradient echo readout train are suspended in real-time, when the respiratory position is outside the predefined gating window. Phase encoding is adapted to deposit the increased signal in central k-space and to minimize signal variation of adjacent k-space profiles. Consistent with the numerical simulation, in vivo experiments demonstrated 35% improvement in blood-pool SNR, without compromising scan time or spatial resolution. The SNR advantage affords great potential towards better depiction of the coronary arteries.