< Terug naar vorige pagina

Publicatie

Validation of the semi-quantitative static SUVR method for $^{18}F-AV45$ PET by pharmacokinetic modeling with an arterial input function

Tijdschriftbijdrage - Tijdschriftartikel

Increased brain uptake of [18F]-AV45 visualized by PET is a key biomarker for Alzheimers disease (AD). The standardized uptake value ratio (SUVR) is widely used for quantification, but is subject to variability based on choice of reference region and changes in cerebral blood flow. Here we validate the SUVR method against the gold standard volume of distribution (VT) to assess cross-sectional differences in plaque load. Methods: Dynamic 60-min [18F]-AV45 (291 ± 67 MBq) and 1-min [15O]-H2O (370 MBq) scans were obtained in 35 age-matched elderly subjects, including 10 probable AD dementia, 15 amnestic mild cognitive impairment (aMCI) and 10 cognitively healthy controls (HC). [18F]-AV45 VT was determined from two-tissue compartment modeling using a metabolite-corrected plasma input function. Static SUVR was calculated at 50-60 min p.i., using either cerebellar gray matter (SUVRCB) or whole subcortical white matter (SUVRWM) as reference. Additionally, whole cerebellum, pons, centrum semiovale and a composite region were examined as alternative references. Blood flow was quantified by [15O]-H2O SUV. Data are presented as mean ± standard error of the mean (SEM). Results: There was rapid metabolization of [18F]-AV45 with only 35% of unchanged parent remaining at 10 minutes. Compared to VT, differences in cortical Aβ-load between aMCI and AD were overestimated by SUVRWM (+4 ± 2%) and underestimated by SUVRCB (-10 ± 2%). VT correlated better with SUVRWM (Pearsons r: from 0.63 for posterior cingulate to 0.89 for precuneus, p < 0.0001) than with SUVRCB (Pearsons r: from 0.51 for temporal lobe (p = 0.002) to 0.82 for precuneus (p < 0.0001)) in all tested regions. Correlation results for the alternative references were in-between those for CB and WM. [15O]-H2O data showed that blood flow was decreased in AD compared to aMCI in cortical regions (-5 ± 1%) and in the reference regions (CB: -9 ± 8%, WM: -8 ± 8%). Conclusion: Increased brain uptake of [18F]-AV45 assessed by the simplified static SUVR protocol does not truly reflect Aβ load. However, SUVRWM is better correlated with VT and more closely reflects VT differences between aMCI and AD than SUVRCB.
Tijdschrift: The Journal of nuclear medicine
ISSN: 0161-5505
Volume: 58
Pagina's: 1483 - 1489
Jaar van publicatie:2017
Trefwoorden:A1 Journal article
BOF-keylabel:ja
BOF-publication weight:10
CSS-citation score:2
Authors from:Higher Education
Toegankelijkheid:Closed