Non-Contrast Enhanced Time-Resolved 4D MRA Using Multi-Bolus TrueSTAR

Lirong Yan¹, Danny JJ Wang¹

Non-contrast time-resolved 4-D MR angiography (MRA) has been proposed recently by combining pulsed ASL with a segmented multi-phase trueFISP sequence (TrueSTAR). However, the SNR of dynamic MRA signal is limited and the labeled blood relaxes within a short duration following the labeling pulse. The present study proposes a novel multi-bolus TrueSTAR technique that employs a train of intermittent inversion pulses interleaved with multi-phase trueFISP acquisitions. The experimental data show that this technique can provide an enhanced and prolonged labeling bolus for dynamic MRA without sacrificing imaging speed or temporal resolution.