Spatial-spectral fat suppression in phase-contrast coronary flow imaging

Magnetic resonance (MR) phase contrast (PC) imaging holds great promise as a noninvasive diagnostic tool for coronary heart disease (CHD) by measuring the blood flow in coronary arteries. Fat signal from the vasculature bed and chest wall generates artifacts in terms of motion ghosts, shifting, and blurring; which hinders vessel segmentation (needed for flow analysis). For a 1.5 Tesla system, the resonance frequency of fat is approximately 220 Hz slower than water. Spatial-spectral (SPSP) pulses utilize this resonance frequency difference to selectively excite either fat or water at a specific location. While SPSP pulses have been shown to be superior over conventional fat saturation pulses, their long durations (10-15 ms) have hindered their use in MR coronary flow imaging, which requires high temporal resolution. Our goal is to design short duration SPSP pulses suitable for PC coronary flow imaging.