MARVEL MRF for Contrast-free Blood Volume, Microvascular Properties, and Relaxometry Mapping: Initial Tests in Volunteers and Stroke Patients

Motivation: An MRF method has been proposed to simultaneously estimate microvascular properties and relaxometry without contrast agent injection. A bidirectional LSTM network has been used to offer ultra-fast MRF reconstruction times. Goal(s): To test the combined MARVEL MRF model in volunteers and patients. Approach: Data were acquired in 9 volunteers. Fully sampled Cartesian, Compressed SENSE, and three spiral undersampling schemes were compared to standard matching. 2 follow-up stroke patients were included. Results: MARVEL produced high-quality maps in seconds from high-SNR acquisitions and an interesting robustness to undersampling schemes. In stroke patients, reconstructed maps highlighted lesions but suffered from motion artifacts. Impact: MARVEL MRF produces high-quality relaxation maps and non-contrast microvascular estimates in seconds from high SNR acquisitions and an interesting robustness to undersampling schemes. Once corrected for motion and shim artifacts, MARVEL could be used for the management of stroke patients.