Low-latency real-time 3D imaging for interventional cardiovascular MRI at 0.55T

Motivation: Interventional cardiovascular magnetic resonance (iCMR) is expected to benefit from real-time 3D imaging, because of the potential for superior device tracking, flexible re-slicing of images, and monitoring of cardiac output. Currently, 2D multi-planar imaging is used to guide iCMR with 3-interleaved slices, each updating approximately every second. Goal(s): To achieve real-time 3D iCMR with ~1 second resolution. Approach: We use a stack-of-spiral bSSFP acquisition at 0.55T with an online spatiotemporally constrained reconstruction. Results: We resolve images at varying spatiotemporal resolutions, with low-latency reconstruction(600-1100ms) and demonstrate image quality in healthy volunteers and during iCMR procedures with gadolinium-filled balloon tracking in naïve pigs. Impact: 3D real-time imaging paired with low-latency image reconstruction and inline image display offers the potential to improve device tracking during MRI-guided cardiac interventions.