title: Risk for Parkinson's disease: twin studies for the detection of asymptomatic subjects using [18F]6-fluorodopa PET.
abstract: Positron emission tomography (PET) studies were carried out with [18F]6-fluorodopa ([18F]6-FD) in monozygotic (MZ) and dizygotic (DZ) twins for the clarification of dopaminergic function. Four MZ and four DZ pairs of twins, each pair consisting of a parkinsonian index case and an asymptomatic co-twin, were collected from the Nationwide Twin Cohort. The control group comprised 14 healthy volunteers. [18F]6-FD PET examinations with a Siemens/CTI 931/08 scanner were performed dynamically over 90 min. The regions-of-interest analysis included the caudate, the putamen and the occipital reference regions. Patlak plots were calculated using occipital tissue input function. The accumulation of [18F]6-FD in the putamen of the asymptomatic co-twins was significantly lower than that in the normal subjects. This result implies that there may be a preclinical stage of Parkinson's disease in the apparently normal co-twins at the time of the PET study.
authors.affiliation: Department of Neurology, University of Turku, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Laihinen
authors.forename: H
authors.initials: H
authors.lastname: Ruottinen
authors.forename: J O
authors.initials: JO
authors.lastname: Rinne
authors.forename: M
authors.initials: M
authors.lastname: Haaparanta
authors.forename: J
authors.initials: J
authors.lastname: Bergman
authors.forename: O
authors.initials: O
authors.lastname: Solin
authors.forename: M
authors.initials: M
authors.lastname: Koskenvuo
authors.forename: R
authors.initials: R
authors.lastname: Marttila
authors.forename: U K
authors.initials: UK
authors.lastname: Rinne
mesh_terms: D000704:Analysis of Variance; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000000981:diagnostic imaging*; D012307:Risk Factors; D014055:Tomography, Emission-Computed
chemical_list: C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine