title: Rate of 6-[18F]fluorodopa uptake decline in striatal subregions in Parkinson's disease.
abstract: BACKGROUND
  Rate of decline in 6-L-[(18)F]fluorodopa (FDOPA) uptake within the striatum has been reported as showing regional differences in Parkinson's disease (PD).
  
  
  METHODS
  We acquired longitudinal brain FDOPA positron emission tomography (PET) studies in 26 PD subjects and 11 controls over 4.5 years. We analyzed both spatially normalized voxel-wise maps of radiotracer influx (Kocc) and average Kocc values for six non-overlapping volumes of interest (VOIs) encompassing the striatum.
  
  
  RESULTS
  The voxel-wise analysis showed that in PD, FDOPA Kocc decline spanned the striatum but was greatest in the posterior putamen ipsilateral and anterior putamen contralateral to initial symptoms. The VOI approached showed that absolute rates of Kocc decline were significantly greater in PD than control subjects, but that the slope of decline did not differ between subregions. In PD, ratios of uptake between subregions did not change during the study with the exception of the ipsilateral putamen/caudate ratio. Decline rates were marginally greater during earlier time segments. Both male gender and advancing age were associated with lower baseline FDOPA uptake, but no difference in decline rates. VOI Kocc values were significantly correlated with disease duration, but only moderately correlated with clinical measures.
  
  
  CONCLUSIONS
  We conclude that FDOPA uptake in subregions of the striatum is strongly correlated with disease duration and age, and declines approximately equally from symptom onset in PD. This implies that in idiopathic PD, relative preservation of uptake in the anterior striatum reflects a delay in pathologic involvement of nigrostriatal projections to this region.
authors: William S. Middleton Memorial Veterans Hospital, Madison, Wisconsin 53792, USA. gallagher@neurology.wisc.edu
authors: Catherine L
authors: CL
authors: Gallagher
authors: Terrence R
authors: TR
authors: Oakes
authors: Sterling C
authors: SC
authors: Johnson
authors: Moo K
authors: MK
authors: Chung
authors: James E
authors: JE
authors: Holden
authors: Barbara B
authors: BB
authors: Bendlin
authors: Donald G
authors: DG
authors: McLaren
authors: Guofan
authors: G
authors: Xu
authors: Robert J
authors: RJ
authors: Nickles
authors: Robert
authors: R
authors: Pyzalski
authors: Onofre
authors: O
authors: DeJesus
authors: W Douglas
authors: WD
authors: Brown
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000473:pathology*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000187:drug effects / Q000493:pharmacokinetics; D015259:Dopamine Agents / Q000493:pharmacokinetics; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000473:pathology*; D013997:Time Factors; D014055:Tomography, Emission-Computed / Q000379:methods
chemical_list: D015259:Dopamine Agents; D005462:Fluorine Radioisotopes; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine