title: Metabolic patterns in prion diseases: an FDG PET voxel-based analysis.
abstract: OBJECTIVE
  Clinical diagnosis of human prion diseases can be challenging since symptoms are common to other disorders associated with rapidly progressive dementia. In this context, (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) might be a useful complementary tool. The aim of this study was to determine the metabolic pattern in human prion diseases, particularly sporadic Creutzfeldt-Jakob disease (sCJD), the new variant of Creutzfeldt-Jakob disease (vCJD) and fatal familial insomnia (FFI).
  
  
  METHODS
  We retrospectively studied 17 patients with a definitive, probable or possible prion disease who underwent FDG PET in our institution. Of these patients, 12 were diagnosed as sCJD (9 definitive, 2 probable and 1 possible), 1 was diagnosed as definitive vCJD and 4 were diagnosed as definitive FFI. The hypometabolic pattern of each individual and comparisons across the groups of subjects (control subjects, sCJD and FFI) were evaluated using a voxel-based analysis.
  
  
  RESULTS
  The sCJD group exhibited a pattern of hypometabolism that affected both subcortical (bilateral caudate, thalamus) and cortical (frontal cortex) structures, while the FFI group only presented a slight hypometabolism in the thalamus. Individual analysis demonstrated a considerable variability of metabolic patterns among patients, with the thalamus and basal ganglia the most frequently affected areas, combined in some cases with frontal and temporal hypometabolism.
  
  
  CONCLUSIONS
  Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease.
authors.affiliation: Nuclear Medicine Department, Clínica Universidad de Navarra, 36, Pío XII Avenue, 31008, Pamplona, Spain, eprietoaz@unav.es.
authors.forename: Elena
authors.initials: E
authors.lastname: Prieto
authors.forename: Inés
authors.initials: I
authors.lastname: Domínguez-Prado
authors.forename: Mario
authors.initials: M
authors.lastname: Riverol
authors.forename: Sara
authors.initials: S
authors.lastname: Ortega-Cubero
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Ribelles
authors.forename: María Rosario
authors.initials: MR
authors.lastname: Luquin
authors.forename: Purificación
authors.initials: P
authors.lastname: de Castro
authors.forename: Javier
authors.initials: J
authors.lastname: Arbizu
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D057054:Molecular Imaging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D017096:Prion Diseases / Q000000981:diagnostic imaging / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18