Flexible Phase-Encoding in 3D Coronary MRA with Balanced SSFP

Ek Tsoon Tan¹, Luca Marinelli¹, Thomas K. Foo¹, Christopher J. Hardy¹

Standard breath-held 3D CMRA uses linear phase-encoding, and is challenging because of variation in patients cardiac quiescent period and breath-holding abilities. Flexible phase-encoding allows for acquisition window and breath-hold duration to be flexibly adjusted, and can provide 25-30% reduction in acquisitions due to removal of k-space corner samples. A novel and compact flexible-linear scheme was tested in balanced SSFP CMRA. Compared to linear phase-encoding (14 heart-beats), flexible phase-encoding in vivo provided either reduced acquisition window by 30% (14 heart-beats) or a reduced breath-hold duration (9 heart-beats).