In Vivo Detection of Monoaminergic Degeneration in Early Parkinson Disease by 18F-9-Fluoropropyl-(1)-

a novel radiotracer targeting vesicular monoamine transporter type 2 (VMAT2), has been proven as a useful imaging marker to measure dopaminergic integrity.Methods: The aim of this study was to eval-uate the capability of 18F-DTBZ PET in detecting the monoaminergic degeneration in early Parkinson disease (PD) in vivo. Seventeen age-matched healthy subjects and 30 PD patients at early stage of disease (duration of disease # 5 y) with mild and unilateral motor symptoms underwent 18F-DTBZ PET scans. The severity of dis-ease, including Unified Parkinson Disease Rating Scale and modi-fied Hoehn and Yahr Stage (mHY), were recorded at off-medication states. The standardized volumes of interest were applied to the spatial normalized image for quantification analysis. The specific uptake ratios (SURs) were calculated according to the formula (spe-cific volumes-of-interest counts/occipital cortex counts) 2 1. SUR measurements were summarized for each brain region. Results