Figure 5b: Images in 54-year-old man with long history of diabetes and increasing claudication of right leg. (a, b) Coronal steady-state gadofosveset trisodium–enhanced MR image (a) and magnified view (b) of thigh and knee (4.3/1.4, 25° flip angle) at 0.125-mm3 spatial resolution show large aneurysm of right distal superficial femoral artery, with complete occlusion of vessel, which is substituted by collateral vessels (arrow). A small aneurysm (arrowhead) of the distal superficial femoral artery without significant stenosis is also seen in left leg. (c) Curved MPRs show course of distal superficial femoral artery and popliteal artery in right and left legs, sites of vessel occlusion (arrows) in right leg, and vessel wall irregularities in left leg. Contrast-enhanced venous structures like the right popliteal vein (arrowhead) do not interfere in making the clinical diagnosis. (d) Findings on state-of-the-art MR angiogram of lower leg vessels enhanced with a conventional MR contrast agent (reference standard) and obtained at 1-mm3 spatial resolution confirm superficial femoral artery occlusion on right side, but image fails to depict details of aneurysms on both sides, as in c.