RT Journal Article
SR Electronic
T1 Reshaping the Amyloid Buildup Curve in Alzheimer Disease? Partial-Volume Effect Correction of Longitudinal Amyloid PET Data
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1820
OP 1824
DO 10.2967/jnumed.119.238477
VO 61
IS 12
A1 Michael Rullmann
A1 Anke McLeod
A1 Michel J. Grothe
A1 Osama Sabri
A1 Henryk Barthel
YR 2020
UL http://jnm.snmjournals.org/content/61/12/1820.abstract
AB It was hypothesized that the brain β-amyloid buildup curve plateaus at an early symptomatic stage of Alzheimer disease (AD). Atrophy-related partial-volume effects (PVEs) degrade signal in hot-spot imaging techniques such as amyloid PET. The current study, a longitudinal analysis of amyloid-sensitive PET data, investigated the effect on the shape of the β-amyloid curve in AD when PVE correction (PVEC) is applied. Methods: We analyzed baseline and 2-y follow-up data for 216 symptomatic individuals on the AD continuum (positive amyloid status) enrolled in the Alzheimer’s Disease Neuroimaging Initiative (17 with AD dementia and 199 with mild cognitive impairment), including 18F-florbetapir PET, MRI, and Mini Mental State Examination scores. For PVEC, the modified Müller–Gärtner method was performed. Results: Compared with non–PVE-corrected data, PVE-corrected data yielded significantly higher changes in regional and composite SUV ratio (SUVR) over time (P = 0.0002 for composite SUVRs). Longitudinal SUVR changes in relation to Mini Mental State Examination decreases showed a significantly higher slope for the regression line in the PVE-corrected than in the non–PVE-corrected PET data (F1 = 7.1, P = 0.008). Conclusion: These PVEC results indicate that the β-amyloid buildup curve does not plateau at an early symptomatic disease stage. A further evaluation of the impact of PVEC on the in vivo characterization of time-dependent AD pathology, including the reliable assessment and comparison of other amyloid tracers, is warranted.