Figure 13b. Stress angiography was performed in a 45-year-old woman who experienced calf claudication walking uphill but was otherwise healthy and a nonsmoker. (a) Angiogram obtained with the foot in a relaxed, neutral position demonstrates no stenosis of the popliteal artery. (b) Angiogram obtained with the foot in dorsiflexion shows stenosis of the artery (arrow). MR imaging was used to define the normal position of the artery relative to the muscle, and a diagnosis of functional PAES was made.