Inflow MR angiography: phantom studies of simulated plaques and aneurysms

The reduction of simulated plaques in a steady state and pulsatile flow phantom using inflow MR (magnetic resonance) angiography is evaluated. It was found that inflow MR angiography can detect subcritical plaques of 0.25 mm to 4.00 mm sizes with either steady state or pulsatile flow. Detected lesions appeared up to 50% larger than the actual size in the simulated plaque study. The results of the aneurysm study were not as positive. Aneurysms were much more difficult to detect due to signal void in the aneurysms. In some cases where the aneurysms were small, the aneurysm could not be detected. The angle of positive identification is important for the detection of lesions. This is even more important in the case of aneurysms, because vessels normally have high signals and can obscure even large lesions at some angle