FIGURE 2.  Representative parametric cardiac PET images and polar maps of ¹¹C-HED retention. PET images are short-axis (SA), vertical long-axis (VLA), and horizontal long-axis (HLA) views for each subject. All PET images were normalized to integral of blood curve for each study, providing parametric ¹¹C-HED RI images. PET images and polar maps of ¹¹C-HED retention are all scaled to common maximum of 0.090 mL of blood per min per mL of tissue. For rainbow color table used, areas of low ¹¹C-HED retention are shown in purple, blue and blue–green, moderate retention is shown in green and yellow, and normal retention is shown in orange, red, pink, and white. NC 3 images show high, uniform ¹¹C-HED uptake in healthy control subject. IPD 6 images show extensive and severe denervation, as seen in 4 patients with IPD. MSA 2 images show extensive and severe denervation, as seen in 2 patients with MSA. MSA 8 images show nonuniform, more focal regional denervation, as seen in 2 patients with MSA. PSP 4 images show large regions of cardiac denervation, as seen in 2 patients with PSP. A = anterior wall; L = lateral wall; S = septal wall.