Fig. 2
MRA visualization of the iliac arteries demonstrating examples of each of the five categorical vessel scores. a Grade 0. b Grade 1—diffuse irregularity of the vessel wall, none of which is causing >50 % stenosis. c Grade 2—50–70 % stenosis in the proximal external iliac. d Grade 3—>70 % stenosis in the common iliac. e Grade 4—complete occlusion of the external iliac just after the bifurcation of the common iliac with compensatory dilation of the internal iliac artery evident