A comparison of FDG‐PET and blood flow SPECT in the diagnosis of neurodegenerative dementias: a systematic review

Abstract

Overall, although studies suggest superiority of PET over SPECT, the evidence base for this is actually quite limited. We suggest that further direct comparative studies, including health economic and patient preference evaluations, are needed to help direct future service provision.

Impact of 18FDG PET and 11C-PIB PET brain imaging on the diagnosis of Alzheimer’s disease and other dementias in a regional memory clinic in Hong Kong

“…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.…”

“…11 In a systematic review, the sensitivity and specificity for 18 F-FDG PET in distinguishing between AD and DLB was 83%-99% and 71%-93%, respectively; and the sensitivity and specificity for 18 F-FDG PET in distinguishing between AD and FTD was 97.6%-99% and 65%-86%, respectively. 11 In the same systematic review, 18 F-FDG PET predicted patients with mild cognitive impairment (MCI) deteriorating into dementia with sensitivity and specificity of 81%-82% and 86%-90%, respectively. 11 Besides, 11 C-PIB can detect the presence of fibrillar amyloid plaques that are a neuropathological marker of AD.…”

“…11 In the same systematic review, 18 F-FDG PET predicted patients with mild cognitive impairment (MCI) deteriorating into dementia with sensitivity and specificity of 81%-82% and 86%-90%, respectively. 11 Besides, 11 C-PIB can detect the presence of fibrillar amyloid plaques that are a neuropathological marker of AD. 13 Correlation studies with neuropathology have shown a sensitivity of 90% and specificity of 100%; 11 C-PIB can reasonably distinguish AD from other types of dementia, eg FTD.…”

“…Cerebellar grey matter was chosen as reference tissue. In this study, 11 C-PIB PET scans were rated as positive (PIB + ; if binding occurred in more than one cortical brain region; ie frontal, parietal, temporal, or occipital) or negative (PIB -; if predominantly white matter binding).…”

18F-FDG PET and Perfusion SPECT in the Diagnosis of Alzheimer and Lewy Body Dementias

“…Studies for 18 F-FDG PET generally report higher accuracy, with sensitivities of 75%-99% for AD and specificities of 71%-93% (9). However, there have been few direct head-to-head comparisons, limited by small sample sizes and showing mixed results (10). For example, although some studies have suggested slight superiority of 18 F-FDG PET for diagnostic accuracy, in the largest study to date, both HMPAO SPECT and 18 F-FDG PET were able to completely separate all 26 AD cases from controls (11).…”