USPIO enhanced 4D flow imaging of the mouse cardiovascular system at 7T with an ultrashort echo time sequence

Background Time resolved phase contrast imaging is hardly used in small animal studies due to a lack of signal-to-noise ratio. Some studies were performed in 2D and one publication (Janiczek et al, MRM 2011) reported flow measurement in mouse aortic arch in 3D due to the use of a thin excitation slab and high Time-Of-Flight (TOF) effect. However, this strategy is not applicable on the whole cardiopulmonary system. To overcome this problem we proposed to combined Ultra-short Echo Time sequence with an injection of Ultra Small Particles of Iron Oxide (USPIO) to generate a stable, positive and high blood signal. The method was first validated on phantom and then applied on the whole cardiopulmonary system of normal mice.