Figure 4a.

Visualization of dopamine transporters at ¹²³I ioflupane SPECT. (a) ¹²³I ioflupane SPECT image obtained in a healthy subject shows two symmetric comma- or crescent-shaped regions of activity mirrored about the median plane. (b–d) ¹²³I ioflupane SPECT images show abnormal patterns, including mild abnormality with asymmetric decreased putaminal activity (arrow in b), moderate abnormality with no putaminal activity but preserved caudate activity (arrows in c), and severe abnormality with no putaminal activity and greatly reduced activity in one or both caudate nuclei (arrowhead in d).