Contrast-free Blood Volume, Microvascular Properties and Relaxometry mapping using bSSFP MR Fingerprinting ; Mesures sans agent de contraste de volume sanguin cérébrale, de propriétés microvasculaires et de relaxométrie à l'aide de bSSFP MR Fingerprint

International audience ; Motivation: Most MR methods for quantifying microvascular properties involve the injection of exogenous contrast agents (CA). Goal(s): We propose an innovative MRI method that simultaneously maps the deoxygenated cerebral blood volume (CBV), microvascular geometry (averaged vessel radius), and relaxometry (T 1 &T 2 ) without CA injection. Approach: Acquisitions are made using a multi-echo, phase-cycled, bSSFP-sequence acquired in transient and pseudo-steady-state regimes. Reconstruction of the maps is made under the MRFingerprinting framework using realistic 3D microvessel representations. Magnetic field distributions (B 1 &B 0 ) are also taken into account. Results: Preliminary results on five healthy volunteers are in line with previous measurements made with MRF and PWI with gadolinium injection. Impact: We propose a contrast-free quantification technique of microvascular properties and relaxation times. It could be useful for functional experiments as well as clinical investigations of several cerebrovascular pathologies including stroke and cancer.