Figure 8

Based on conventional phase-contrast MRA and driven by the increase in available post-processing computing power, a new vascular imaging technique with great clinical potential has evolved in the past few years: a flow-sensitive, 3-dimensional, and 3-directional time-resolved gradient echo sequence--often referred to as 7D-MRA. This figure illustrates the evaluation of renal artery stenosis using DSA for reference (A) and MRA (B). The flow alterations around the stenosis present can not only be visualized on color coded post-processed 7D-MRA parameter maps (C) with red indicating increased post stenotic flow, but also the trans-stenotic pressure gradient can also be quantified (D) using the Bernoulli equation. Courtesy of PD Dr. Bley, UKE Hamburg.