Time-resolved contrast-enhanced imaging with isotropic resolution and broad coverage using an undersampled 3D projection trajectory

摘要: Time-resolved contrast-enhanced 3D MR angiography (MRA) methods have gained in popularity but are still limited by the tradeoff between spatial and temporal resolution. A method is presented that greatly reduces this employing undersampled projection reconstruction trajectories. The variable density k-space sampling intrinsic to sequence combined with interpolation provide time frames as short 4 s. This resolution need for exact contrast timing while also providing dynamic information. Spatial determined primarily readout thus isotropic across FOV, which isotropic. Although undersampling outer regions of introduces aliased energy into image, may compromise resolution, not a limiting factor high-contrast applications such MRA. Results from phantom volunteer studies demonstrating broad coverage an field view (FOV), minimal artifacts, In one application, single breath-hold exam covering entire pulmonary vasculature generates high-resolution, imaging volumes depicting bolus passage.