Novel rapid fat suppression strategy with spectrally selective pulses

Abstract

Short repetition time gradient echo sequences are gaining popularity in clinical applications such as dynamic contrast enhancement imaging, cardiac imaging, and MR angiography. Performing fat suppression in these sequences is usually time consuming and often somewhat ineffective, due to the relatively short T(1) and long T(2) of fat. A novel rapid fat suppression strategy using spectrally selective pulses is introduced and compared with clinically popular sequences such as fat presaturated fast field echo (FFE) and turbo field echo (TFE) and binomial water-selective spatial-spectral excitation (SSE, or SPSP excitation) FFE. The new strategy combines fat presaturation with low-order binomial water-selective SSE pulses in a TFE sequence. This enables the use of a long echo train length to decrease exam time, but without creation of excess fat signal contamination of the resultant images. The fat nullification is also more reliable as fat signals in central k-space data are suppressed twice. An implementation of this strategy is compared with traditional methods in both phantom and human studies, confirming that the new technique provides strong fat suppression with few artifacts despite the short scan duration.