MR GRADIENT-ECHO IMAGING OF INTRAVASCULAR BLOOD OXYGENATION - T-2(ASTERISK) DETERMINATION IN THE PRESENCE OF FLOW

The T-2(*) relaxation time of blood varies with its oxygen saturation. To evaluate the feasibility of imaging intravascular blood oxygenation in humans using a conventional 1.5T WIR system, we have implemented a method to measure T-2(*) of blood despite the presence of pulsatile flow. The method was tested in a) stationary and flow phantoms, b) blood samples at different levels of oxygen saturation, and c) a human hypoxia model. Our results demonstrate the ability of cardiac-triggered, flow compensated gradient echo imaging to obtain reproducible T-2(*) measurements of flowing blood in vivo.