Amyloid PET imaging in large multi-center trials: Technical and practical issues.
Human Amyloid Imaging 2011 Meeting Abstracts. 2011 Jan 15;
Large multicenter trials involving PET have been performed in the field of oncology for the past decade or so.
More recently, multi-center trials involving brain imaging have becoming increasingly common, including studies
funded by NIH or sponsored and coordinated by industry. The Alzheimer's Disease NeuroImaging Initiative (ADNI),
a ~60 site, ~800 subject project funded jointly by NIH and the pharmaceutical industry, and begun in 2004, is one
of the largest of these. Longitudinal PET scans using [18F]FDG and [11C]PiB were performed in a subset of these
subjects, which included the diagnostic groups of MCI, early AD, and normal elderly control. Continuation of
ADNI (ADNI-GO and ADNI 2) has recently started, with subjects in these projects getting both [18F]FDG and now
[18F]AV-45 amyloid scans instead of [11C]PiB.
The talk will focus on both technical and practical issues of amyloid PET imaging specific to multi-center trials.
Topics will cover issues related to the following areas: 1) scanner differences across sites, including both hardware
and software-related differences between vendors and scanner models, which make analysis and interpretation
of results more challenging than for studies performed at a single site. 2) dynamic vs static imaging and the scan
duration used for each approach, which will affect the quantitative results. 3) Use of a bolus versus a partial-bolus
plus constant infusion administration of tracer. 4) Effect of the choice of reference tissue on the precision amyloid
measure. 5) Differences between [11C]PiB and [18F]AV-45. 6) Practical issues and lessons learned from ADNI and
Results from the ADNI and ADNI-GO projects will be used to illustrate the effects that these issues have on our
ability to extract accurate and precise data from amyloid imaging studies using PET, and hence our ability to draw
meaningful and reliable conclusions from the results of these important multi-center trials.