The status of dopamine nerve terminals in Parkinson's disease and essential tremor: a PET study with the tracer [11-C]FE-CIT

Neuroimaging studies of the striatal dopamine transporter (DAT) are useful in the assessment of the dopaminergic system in Parkinson's disease (PD). W e used positron emisson tomography (PET) and the tracer [11-C]FE-CIT to mea sure DAT binding in the caudate nucleus and putamen of 31 patients with PD, 5 with essential tremor and 8 healthy control subjects. Of the patients wi th PD, 17 were drug naive, while the others were either on levodopa or dopa mine agonist monotherapy. DAT binding was significantly reduced in the caud ate nucleus and to a greater extent in the putamen of PD patients compared to both healthy controls and essential tremor individuals. No overlap was o bserved between putamen values in PD and normals. No differences were found between controls and essential tremor subjects. These data confirm that me asurements of DAT binding can provide an accurate and highly sensitive meas ure of degeneration in the dopamine system in PD.