MR Vascular Fingerprinting: A New Approach to Compute Cerebral Blood Volume, Mean Vessel Radius, and Oxygenation Maps in the Human Brain

摘要: In the present study, we describe a fingerprinting approach to analyze time evolution of MR signal and retrieve quantitative information about microvascular network. We used Gradient Echo Sampling Free Induction Decay Spin (GESFIDE) sequence defined fingerprint as ratio signals acquired pre- post-injection an iron-based contrast agent. then simulated same experiment with advanced numerical tool that takes virtual voxel containing blood vessels input, computes microscopic magnetic fields water diffusion effects, eventually derives expected evolution. The parameter inputs simulations (cerebral volume [CBV], mean vessel radius [R], oxygen saturation [SO2]) were varied obtain dictionary all possible evolutions. best fit between observed was determined by using least square minimization. This evaluated in 5 normal subjects results compared those obtained more conventional methods, steady-state imaging for CBV R global measure oxygenation from superior sagittal sinus SO2. method enabled creation high-resolution parametric maps network showing fine details. Numerical values gray matter (CBV=3.1±0.7%, R=12.6±2.4μm, SO2=59.5±4.7%) are consistent literature reports correlated approaches. SO2 white (53.0±4.0%) slightly lower than expected. Numerous improvements can easily be made should useful study brain pathologies.