Echo-uT1RESS Sequence with Radial Stack-of-Stars Acquisition for Dynamic Contrast-Enhanced Dark Blood Imaging

Motivation: Scans with dark-blood contrast can improve the conspicuity of small metastases in contrast-enhanced brain examinations and may be useful for vessel-wall imaging. Goal(s): To describe a novel sequence, called echo-uT1RESS, that overcomes the limitations of the frequently utilized T1 SPACE sequence. Approach: The proposed stack-of-stars echo-uT1RESS sequence applies saturation-recovery preparation followed by 3D PSIF readout. Due to radial k-space acquisition, scans are motion-insensitive and can be acquired during free breathing. Dynamic contrast-enhanced images can be obtained through GRASP reconstruction. Results: Evaluation in a small patient cohort demonstrated high conspicuity of enhancing lesions and vessel walls with reduced motion artifacts compared to conventional sequences. Impact: The described radial echo-uT1RESS sequence offers improved lesion-to-background and dark-blood contrast. The sequence may help to increase the sensitivity for detecting small metastases and may find application in vessel-wall imaging. It is also compatible with dynamic imaging using GRASP reconstruction.