Fig. 5.

DAT availability in the putamen measured with FE-PE2I versus FP-CIT. Scatterplot of DAT availability in the putamen measured with FE-PE2I (BP_ND) versus FP-CIT (SUR) in patients and HC. DAT measurements are mean of the left and right putamen. Empty squares indicate HC that are not yet followed up. Filled squares indicate HC that are still healthy at follow-up after 2 years. Filled circles indicate patients that fulfilled clinical criteria for PS at inclusion and fulfilled clinical criteria for a specific parkinsonian syndrome at follow-up after 2 years. Empty circles indicate patients that fulfilled clinical criteria for PS at inclusion, not yet clinically followed up. Filled triangles indicate patients that fulfilled clinical criteria for PS at inclusion, but did not fulfil clinical criteria for a specific parkinsonian syndrome at follow-up after 2 years. DAT, dopamine transporter; BP_ND, binding potential relative to non-displaceable binding; SUR, specific uptake ratio; FE-PE2I, [¹⁸F]FE-PE2I PET; FP-CIT, [¹²³I]FP-CIT SPECT; PS, parkinsonian syndrome; HC, healthy controls