Meta-analytic comparison between PIB-PET and FDG-PET results in Alzheimer's disease and MCI.
Level 3 - non-randomized controlled study
Meta-analysis of observational case-control imaging studies
PubMed 25370296 · doi:10.1007/s12013-014-0138-7
What was done
The authors performed a voxel-based meta-analysis using effect-size signed differential mapping (ES-SDM) to examine positron emission tomography (PET) abnormalities in Alzheimer's disease (AD) and mild cognitive impairment (MCI). Studies utilizing either Pittsburgh Compound-B (PIB-PET) to measure amyloid retention or 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) to measure glucose metabolism were analyzed. The meta-analysis included 24 studies encompassing 728 AD patients, 211 MCI patients, and 658 healthy controls.
What was found
Individuals with AD exhibited significant PIB retention relative to controls in the bilateral precuneus, temporal, supramarginal, cingulate, and fusiform gyri, as well as the right insula and putamen. In FDG-PET, AD patients showed significant hypometabolism across bilateral precuneus, temporal, supramarginal, cingulate, fusiform, angular, inferior parietal, and middle frontal gyri, plus the left precentral and parahippocampal gyri, right superior frontal gyrus, and thalamus. An exploratory analysis of MCI studies identified mildly reduced glucose metabolism matching the regional pattern seen in AD. No specific numerical effect sizes or statistics were reported in the abstract.
Why it matters
It maps the shared anatomical distribution of amyloid deposition and glucose hypometabolism across AD and MCI, helping define regions of interest for neuroimaging research.
Limits
The source data derive from observational case-control studies. The MCI findings were explicitly exploratory and based on few studies. Numerical estimates, demographic details, and tracer-specific statistical thresholds are omitted in the abstract.
Cited by
- supports Patients with Alzheimer's disease show significantly reduced FDG signal on PET imaging compared to healthy controls.