A robust broadband fat-suppressing phaser T -preparation module for cardiac magnetic resonance imaging at 3T.

PURPOSE

Designing a new T -preparation (T -Prep) module to simultaneously provide robust fat suppression and efficient T preparation without requiring an additional fat-suppression module for T -weighted imaging at 3T.

METHODS

The tip-down radiofrequency (RF) pulse of an adiabatic T -Prep module was replaced by a custom-designed RF-excitation pulse that induces a phase difference between water and fat, resulting in a simultaneous T preparation of water signals and the suppression of fat signals at the end of the module (a phaser adiabatic T -Prep). Numerical simulations and in vitro and in vivo electrocardiogram (ECG)-triggered navigator-gated acquisitions of the human heart were performed. Blood, myocardium, and fat signal-to-noise ratios and right coronary artery vessel sharpness were compared against previously published adiabatic T -Prep approaches.

RESULTS

Numerical simulations predicted an increased fat-suppression bandwidth and decreased sensitivity to transmit magnetic field inhomogeneities using the proposed approach while preserving the water T -Prep capabilities. This was confirmed by the tissue signals acquired in the phantom and the in vivo images, which show similar blood and myocardium signal-to-noise ratio, contrast-to-noise ratio, and significantly reduced fat signal-to-noise ratio compared with the other methods. As a result, the right coronary artery conspicuity was significantly increased.

CONCLUSION

A novel fat-suppressing T -Prep method was developed and implemented that showed robust fat suppression and increased vessel sharpness compared with conventional techniques while preserving its T -Prep capabilities.