title: Management impact of FDG-PET in dementia: results from a tertiary center memory clinic.
abstract: BACKGROUND
  2-[18F]fluoro-2-Deoxy-D-glucose (FDG) positron emission tomography (PET) may assist the diagnosis of dementia but it is an expensive investigation.
  
  
  OBJECTIVE
  To obtain management impact data for FDG-PET in dementia.
  
  
  METHODS
  This was a prospective study of 194 consecutive patients referred from a memory clinic for FDG-PET at the discretion of the dementia specialists. Diagnosis and management plans formulated at a multidisciplinary patient review meeting were compared before and after the release of PET findings.
  
  
  RESULTS
  FDG-PET had moderate to high impact on the diagnosis and management in 85 (44%) participants. Diagnosis changed from probable neurodegenerative disease in 27 patients to a non-degenerative diagnosis and vice versa in 12 patients. PET changed the type of dementia in another 29 (15%) participants and prescription of cholinesterase inhibitors in 33 patients (17%). Number of uncertain diagnoses reduced from 58 to 35 (p < 0.001, χ2 = 15.12), differential diagnoses reduced from 127 to 55 (p = 0.003) and very probable diagnoses increased from 5 to 42 (p ≤ 0.001, χ2 = 1.01). Mini-Mental State Examination score was higher in those where PET had high diagnostic impact (26.3 ± 3.1 versus 23.9 ± 5.1, p ≤ 0.05). The degree of impact correlated with the pre-scan level of diagnostic uncertainty (ρ = -0.258, p < 0.001).
  
  
  CONCLUSIONS
  The management impact was higher in those with greater diagnostic uncertainty and in those with less severe cognitive impairment. The findings suggest that FDG-PET is a useful adjunct for the management of suspected dementing disorders in appropriately selected patients.
authors: Department of Nuclear Medicine and Centre for PET, Austin Health, The University of Melbourne, VIC, Australia.
authors: Alby
authors: A
authors: Elias
authors: Department of Aged Care, Austin Health, Melbourne, VIC, Australia.
authors: Michael
authors: M
authors: Woodward
authors: Department of Nuclear Medicine and Centre for PET, Austin Health, The University of Melbourne, VIC, Australia.
authors: Christopher C
authors: CC
authors: Rowe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001037:Aphasia / Q000000981:diagnostic imaging; D001921:Brain / Q000000981:diagnostic imaging*; D016009:Chi-Square Distribution; D003704:Dementia / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography / Q000379:methods*; D012189:Retrospective Studies; D062606:Tertiary Care Centers
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Alzheimer's disease; FDG-PET; diagnostic impact; memory clinic