Dynamic four-dimensional MR angiography of the chest and abdomen.

Time-resolved (four-dimensional) contrast-enhanced MR angiography (CE-MRA) circumvents many of the adverse effects and limitations of conventional x-ray digital subtraction angiography. Four-dimensional CE-MRA uses improvements in gradient hardware, pulse sequences, or computational power to reduce scan times to seconds or less, allowing rapid sequential acquisitions within a single breath hold. These techniques eliminate the need for contrast bolus timing, ensure acquisition of the peak vascular phase of interest, and provide information on the dynamics of contrast arrival and hemodynamic consequences of complex vascular pathologies. This article reviews the techniques used to perform four-dimensional CE-MRA and provides an overview of how to use these techniques in CE-MRA of the chest and abdomen.