Impact of (18)FDG PET and (11)C-PIB PET brain imaging on the diagnosis of Alzheimer's disease and other dementias in a regional memory clinic in Hong Kong.
OBJECTIVE
This study investigated the improvement in the accuracy of diagnosis of dementia subtypes among Chinese dementia patients who underwent [18F]-2-fluoro-2-deoxy-D-glucose positron emission tomography ((18)FDG PET) with or without carbon 11-labelled Pittsburgh compound B ((11)C-PIB).


METHODS
This case series was performed in the Memory Clinic at Queen Mary Hospital, Hong Kong. We reviewed 109 subjects (56.9% were female) who received PET with or without (11)C-PIB between January 2007 and December 2014. Data including age, sex, education level, Mini-Mental State Examination score, Clinical Dementia Rating scale score, neuroimaging report, and pre-/post-imaging clinical diagnoses were collected from medical records. The agreement between the initial and post-PET with or without (11)C-PIB dementia diagnosis was analysed by the Cohen's kappa statistics.


RESULTS
The overall accuracy of initial clinical diagnosis of dementia subtype was 63.7%, and diagnosis was subsequently changed in 36.3% of subjects following PET with or without (11)C-PIB. The rate of accurate initial clinical diagnosis (compared with the final post-imaging diagnosis) was 81.5%, 44.4%, 14.3%, 28.6%, 55.6% and 0% for Alzheimer's disease, dementia with Lewy bodies, frontotemporal dementia, vascular dementia, other dementia, and mixed dementia, respectively. The agreement between the initial and final post-imaging dementia subtype diagnosis was only fair, with a Cohen's kappa of 0.25 (95% confidence interval, 0.05-0.45). For the 21 subjects who underwent (11)C-PIB PET imaging, 19% (n=4) of those with Alzheimer's disease (PIB positive) were initially diagnosed with non-Alzheimer's disease dementia.


CONCLUSIONS
In this study, PET with or without (11)C-PIB brain imaging helped improve the accuracy of diagnosis of dementia subtype in 36% of our patients with underlying Alzheimer's disease, dementia with Lewy bodies, vascular dementia, and frontotemporal dementia.
Division of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.
Y F
YF
Shea
Division of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.
J
J
Ha
Division of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.
S C
SC
Lee
Division of Geriatrics, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong.|The Alzheimer's Disease Research Network, SRT Ageing, The University of Hong Kong, Pokfulam, Hong Kong.
L W
LW
Chu
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging*; D000814:Aniline Compounds; D001921:Brain / Q000000981:diagnostic imaging*; D003704:Dementia / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D057180:Frontotemporal Dementia / Q000000981:diagnostic imaging; D006801:Humans; D020961:Lewy Body Disease / Q000000981:diagnostic imaging; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D013844:Thiazoles
C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D000814:Aniline Compounds; D019275:Radiopharmaceuticals; D013844:Thiazoles; D019788:Fluorodeoxyglucose F18
Alzheimer disease/radionuclide imaging; Fluorodeoxyglucose F18; Positron-emission tomography/methods