Nicole Seiberlich1, Gregory Lee1,
Philipp Ehses2, Jeffrey Duerk1,3, Mark Griswold1,3
1Radiology, University
Hospitals of Cleveland, Cleveland, OH, United States; 2Research
Center for Magnetic Resonance Bavaria (MRB), Wuerzburg, Germany; 3Biomedical
Engineering, Case Western Reserve University, Cleveland, OH, United States
Through-time non-Cartesian GRAPPA has recently emerged as a technique for real-time MRI, where images acquired using an undersampled radial trajectory could be reconstructed to yield a temporal resolution better than 50 ms/image. This through-time GRAPPA method has been extended to the more efficient variable density spiral trajectory in order to scan at a higher frame rate with a lower acceleration factor than with radial. Using through-time spiral GRAPPA and highly undersampled spiral data (R=12), short axis cardiac SSFP images can be generated with a temporal resolution of 17.9ms/image (a frame rate of 56 images/s) without any echo sharing.