Equilibrium Phase Contrast-Enhanced MRA: Comparison of Novel Cartesian bT1RESS and Stack-of-Stars CM-FISS Imaging Strategies

Motivation: Balanced T1 relaxation-enhanced steady-state (bT1RESS) allows diagnostic angiograms to be obtained for many minutes after gadolinium contrast administration, but further improvements in image quality would be beneficial. Goal(s): We hypothesized that a radial stack-of-stars contrast-modified fast interrupted steady-state (CM-FISS) technique could provide equilibrium phase contrast-enhanced MRA with decreased motion sensitivity and improved fat suppression compared with Cartesian bT1RESS. Approach: Equilibrium phase contrast-enhanced MRA were obtained of the chest, abdomen, and extracranial carotid arteries in volunteers and patients. Results: Both techniques provided excellent visualization of arteries and veins. Whereas bT1RESS was more flexible, CM-FISS provided better fat suppression and small vessel conspicuity. Impact: Equilibrium phase contrast-enhanced MRA using bT1RESS is a recently described paradigm-shifting approach for vascular imaging. As a potential alternative to Cartesian bT1RESS, we implemented a radial stack-of-stars CM-FISS technique which provides improved fat suppression and reduced motion sensitivity.