title: Cortical 6-[18F]fluoro-L-dopa uptake and frontal cognitive functions in early Parkinson's disease.
abstract: Patients with Parkinson's disease (PD) have already at the early stages of the disease impaired performance especially in tests measuring frontal lobe functions such as attention. The pathophysiological basis of these deficits is unclear. In the present study, 21 non-demented, non-medicated patients at the early stage of PD and 24 healthy controls underwent a positron emission tomography (PET) scan with 6-[18F]fluoro-L-dopa (Fdopa) as the tracer. In addition, the PD patients performed a neuropsychological test battery, including a test measuring sustained attention (VIG) and a test requiring suppressed attention (Stroop). Both voxel-based Statistical Parametric Mapping (SPM) and automated region of interest (ROI) analysis were employed. Compared to controls, the PD patients had decreased Fdopa uptake in the striatum and a large cortical area of increased Fdopa uptake. The reaction time in the VIG test correlated positively with the Fdopa uptake of the dorsolateral prefrontal cortex and the performance in the Stroop test correlated negatively with the Fdopa uptake in an area including the medial frontal cortex and the anterior cingulate. The results show that cortical Fdopa uptake is increased in early non-medicated PD and suggest that the changes in frontal Fdopa uptake are related to cognitive impairments found in early PD.
authors.affiliation: Turku PET Center, University of Turku, POB 52, FIN-20521 Turku, Finland.
authors.forename: Anna
authors.initials: A
authors.lastname: Brück
authors.forename: Sargo
authors.initials: S
authors.lastname: Aalto
authors.forename: Elina
authors.initials: E
authors.lastname: Nurmi
authors.forename: Jörgen
authors.initials: J
authors.lastname: Bergman
authors.forename: Juha O
authors.initials: JO
authors.lastname: Rinne
mesh_terms: D000375:Aging / Q000378:metabolism; D002540:Cerebral Cortex / Q000000981:diagnostic imaging* / Q000378:metabolism*; D003072:Cognition Disorders / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000378:metabolism*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014018:Tissue Distribution
chemical_list: D019275:Radiopharmaceuticals; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine