Non-Contrast Outer Radial Inner Square K-Space Scheme (NORISKS)- a Breath-Held Balanced SSFP-Dixon Technique for Non-Contrast Enhanced Renal MRA

Manojkumar Saranathan¹, Pauline W. Worters¹, Shreyas Vasanawala¹

Nephrogenic systemic fibrosis (NSF) concerns associated with Gadolinium based contrast agents have spurred a resurgence in non-contrast enhanced MR Angiography (MRA) methods. Balanced steady state free precession (b-SSFP) imaging [1-3], due to its high SNR/CNR and short scan times, has been successful in coronary and renal angiography. Most current methods use respiratory gating which performs poorly during irregular breathing/sleep apnea. We propose a 3D b-SSFP-Dixon technique with a novel k-space segmentation scheme for breath-held (BH) non-contrast renal MRA without compromising coverage or spatial resolution. The sequence was tested on healthy subjects as well as patients.