PT - JOURNAL ARTICLE AU - Keir, Graham AU - Mashriqi, Faizullah AU - Caravella, Christopher AU - Clouston, Sean A.P. AU - Rini, Josephine N. AU - Franceschi, Ana M. TI - Optimization of [<sup>18</sup>F]-FDOPA Brain PET Acquisition Times for Assessment of Parkinsonism in the Clinical Setting AID - 10.3174/ajnr.A8207 DP - 2024 Jun 01 TA - American Journal of Neuroradiology PG - 781--787 VI - 45 IP - 6 4099 - http://www.ajnr.org/content/45/6/781.short 4100 - http://www.ajnr.org/content/45/6/781.full SO - Am. J. Neuroradiol.2024 Jun 01; 45 AB - BACKGROUND AND PURPOSE: Fluorine 18-fluoro-L-dopa ([18F]-FDOPA) was approved by the FDA in 2019 and reimbursed by the Centers for Medicare &amp; Medicaid Services in 2022 for use with PET to visualize dopaminergic nerve terminals in the striatum for evaluation of parkinsonism. We sought to determine the optimal image acquisition time for [18F]-FDOPA PET by evaluating rater-estimated FDOPA positivity and image quality across 4 time points.MATERIALS AND METHODS: Brain PET/CT was acquired 90 minutes following injection of 185 megabecquerel (5 mCi) of [18F]-FDOPA. PET was acquired in list mode for 20 minutes, and data were replayed to represent 15-, 10-, and 5-minute acquisitions. By means of MIMneuro, PET/MR imaging or PET/CT was independently graded for FDOPA positivity and image quality by 2 readers, blinded to the clinical report and diagnosis. Expert neuroradiologist clinical reads were used as the criterion standard.RESULTS: Twenty patients were included, average age 65.6 years, 55% women. Image-quality ratings decreased with shorter acquisition times for both readers (reader 1, ρ = 0.23, P = .044; reader 2, ρ = 0.24, P = .036), but there was no association between abnormality confidence scores and acquisition time (reader 1, ρ = –0.13, P = .250; reader 2, ρ = –0.19, P = .100). There was a high degree of consistency in intra- and interrater agreement and agreement with the expert reads when using acquisition times of ≥10 minutes (maximal confidence score consistency [ρ = 0.92] and interrater agreement [κ = 0.90] were observed at 15 minutes), while image quality was consistently rated as low and FDOPA positivity ratings were inconsistent when using a 5-minute acquisition time.CONCLUSIONS: Our study suggests that image-quality ratings were stable after 15 minutes and that between-subject abnormality detection rates were highly consistent between the 2 readers when acquired for at least 10 and up to 20 minutes but were inconsistent at 5 minutes. Shorter [18F]-FDOPA PET acquisition times may help maximize patient comfort while increasing throughput in the clinical setting.AADCaromatic amino acid decarboxylaseACattenuation-correctedDaTdopamine transporterPDParksinson diseasePSparkinsonian syndromes