A multicenter assessment of dopamine transporter imaging with DOPASCAN/SPECT in parkinsonism

Background In vivo imaging of the dopamine transporter (DAT) with SPECT is a quantitative biomarker for PD onset and severity. Objective To use a multicenter study to evaluate the diagnostic accuracy of DOPASCAN and SPECT in patients with PD, progressive supranuclear palsy (PSP), and essential tremor (ET), and in healthy controls (HC). Methods Ninety-six individuals with known clinical diagnosis were imaged with DOPASCAN at five sites with different multidetector SPECT systems. Both masked visual interpretation and region of interest (ROI) analysis were performed at each site and at a core analysis center. Results Visual interpretation of the images by an expert panel demonstrated a sensitivity of 0.98 and specificity of 0.83 comparing parkinsonian (PD + PSP) versus nonparkinsonian (ET + HC) controls. Quantitative analysis of putamen and caudate DOPASCAN uptake for each region in the PD or PSP groups was significantly reduced compared to the ET or HC groups. Comparison of parkinsonian (PD + PSP) versus nonparkinsonian (ET + HC) individuals demonstrated a reduction of 76% in mean putamen and 48% in mean caudate DOPASCAN uptake. Conclusions DOPASCAN and SPECT imaging reliably and effectively distinguish between subjects with Parkinson's syndrome (PD + PSP) and without Parkinson's syndrome (HC + ET). This is the first multicenter assessment of dopamine transporter imaging demonstrating that this tool may be used widely to assess dopaminergic degeneration in patients with parkinsonism.–1547