title: Differential diagnosis of parkinsonian syndromes using F-18 fluorodeoxyglucose positron emission tomography.
abstract: BACKGROUND
  Positron emission tomography (PET) imaging with F-18 fluorodeoxyglucose (FDG) has been used to identify characteristic patterns of regional glucose metabolism in patients with idiopathic Parkinson's disease (IPD) and the atypical parkinsonian syndromes of progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal syndrome (CBS). We undertook this study to assess the utility of fluorodeoxyglucose-PET in the differential diagnosis of individual patients with clinical parkinsonism. "Visual" and "computer-supported" reading of the fluorodeoxyglucose-PET scans were used for image interpretation and compared with each other.
  
  
  METHODS
  One hundred thirty-six parkinsonian patients were referred from movement disorder clinics in specialty neurology centers for the fluorodeoxyglucose-PET study. Imaging-based diagnosis was obtained by visual assessment of individual scans by a PET physician blinded to the clinical diagnosis and also by computer-assisted interpretation using statistical parametric mapping (SPM) analysis. The results were compared with a 2-year follow-up clinical assessment made by a movement disorder specialist.
  
  
  RESULTS
  Concordance of visual evaluation of fluorodeoxyglucose-PET with clinical diagnosis was achieved in 91.7% of patients scanned, 97.6% IPD, 80% MSA, 76.6% PSP, and 100% CBS. Blinded computer assessment using SPM was concordant with the clinical diagnosis in 91% of cases evaluated (90.4% IPD, 80% MSA, 93.3% PSP, and 100% CBS).
  
  
  CONCLUSIONS
  Fluorodeoxyglucose-PET performed at the time of initial referral for parkinsonism is useful for the differential diagnosis of IPD, PSP, MSA, and CBS. Computer-assisted methods can be used for objective evaluation especially when expert readers are not available.
authors: Department of Nuclear Medicine & PET, All India Institute of Medical Sciences, New Delhi 110029, India. madhu_deven@yahoo.com
authors: Madhavi
authors: M
authors: Tripathi
authors: Vijay
authors: V
authors: Dhawan
authors: Shichun
authors: S
authors: Peng
authors: Suman
authors: S
authors: Kushwaha
authors: Amit
authors: A
authors: Batla
authors: Abhinav
authors: A
authors: Jaimini
authors: Maria M
authors: MM
authors: D'Souza
authors: Rajnish
authors: R
authors: Sharma
authors: Sanjiv
authors: S
authors: Saw
authors: Anupam
authors: A
authors: Mondal
mesh_terms: D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D020734:Parkinsonian Disorders / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D049268:Positron-Emission Tomography / Q000379:methods* / Q000706:statistics & numerical data*; D015995:Prevalence; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18