Early-stage [123I]β-CIT SPECT and long-term clinical follow-up in patients with an initial diagnosis of Parkinson’s disease

Abstract. Purpose: Previous studies using dopamine transporter single-photon emission computed tomography (SPECT) to try and distinguish between patients with idio-pathic Parkinson’s disease (IPD) and patients with atypical parkinsonian syndromes (APS) have mainly focussed on pa-tients with an already established clinical diagnosis of sev-eral years ’ duration. Differences in the pattern of striatal involvement between IPD andAPS have been found in only few studies. We hypothesized that distinguishing SPECT featuresmight bemost pronounced at an early disease stage, and the purpose of the present study was to investigate this hypothesis. Methods: The study included 72 patients with an initial clinical diagnosis of IPD, supported by decreased striatal [123I]β-CIT binding on baseline SPECT. In ten patients, th