TY - JOUR
T1 - Precision estimates of relative and absolute cerebral blood flow in Alzheimer’s disease and cognitively normal individuals
AU - Heeman, Fiona
AU - Visser, Denise
AU - Yaqub, Maqsood
AU - Verfaillie, Sander
AU - Timmers, Tessa
AU - Pijnenburg, Yolande A. L.
AU - van der Flier, Wiesje M.
AU - van Berckel, Bart N. M.
AU - Boellaard, Ronald
AU - Lammertsma, Adriaan A.
AU - Golla, Sandeep S. V.
N1 - Funding Information: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The acquisitions mentioned in the Acknowledgements section are supported by grants from ZonMW and from the Nuts-Ohra Foundation (Amsterdam, The Netherlands): 0903-044 and 1002-03. Acknowledgements Publisher Copyright: © The Author(s) 2022.
PY - 2022
Y1 - 2022
N2 - Alzheimer’s disease is characterized by regional reductions in cerebral blood flow (CBF). Although the gold standard for measuring CBF is [15O]H2O PET, proxies of relative CBF, derived from the early distribution phase of amyloid and tau tracers, have gained attention. The present study assessed precision of [15O]H2O derived relative and absolute CBF, and compared precision of these measures with that of (relative) CBF proxies. Dynamic [15O]H2O, [18F]florbetapir and [18F]flortaucipir PET test-retest (TrT) datasets with eleven, nine and fourteen subjects, respectively, were included. Analyses were performed using an arterial input model and/or a simplified reference tissue model, depending on the data available. Relative CBF values (i.e. K1/K1′ and/or R1) were obtained using cerebellar cortex as reference tissue and TrT repeatability (i.e. precision) was calculated and compared between tracers, parameters and clinical groups. Relative CBF had significantly better TrT repeatability than absolute CBF derived from [15O]H2O (r = −0.53), while best TrT repeatability was observed for [18F]florbetapir and [18F]flortaucipir R1 (r = −0.23, r = −0.33). Furthermore, only R1 showed, better TrT repeatability for cognitively normal individuals. High precision of CBF proxies could be due to a compensatory effect of the extraction fraction, although changes in extraction fraction could also bias these proxies, but not the gold standard.
AB - Alzheimer’s disease is characterized by regional reductions in cerebral blood flow (CBF). Although the gold standard for measuring CBF is [15O]H2O PET, proxies of relative CBF, derived from the early distribution phase of amyloid and tau tracers, have gained attention. The present study assessed precision of [15O]H2O derived relative and absolute CBF, and compared precision of these measures with that of (relative) CBF proxies. Dynamic [15O]H2O, [18F]florbetapir and [18F]flortaucipir PET test-retest (TrT) datasets with eleven, nine and fourteen subjects, respectively, were included. Analyses were performed using an arterial input model and/or a simplified reference tissue model, depending on the data available. Relative CBF values (i.e. K1/K1′ and/or R1) were obtained using cerebellar cortex as reference tissue and TrT repeatability (i.e. precision) was calculated and compared between tracers, parameters and clinical groups. Relative CBF had significantly better TrT repeatability than absolute CBF derived from [15O]H2O (r = −0.53), while best TrT repeatability was observed for [18F]florbetapir and [18F]flortaucipir R1 (r = −0.23, r = −0.33). Furthermore, only R1 showed, better TrT repeatability for cognitively normal individuals. High precision of CBF proxies could be due to a compensatory effect of the extraction fraction, although changes in extraction fraction could also bias these proxies, but not the gold standard.
KW - Alzheimer’s disease
KW - Cerebral blood flow
KW - PET
KW - healthy controls
KW - precision
UR - http://www.scopus.com/inward/record.url?scp=85140614952&partnerID=8YFLogxK
U2 - https://doi.org/10.1177/0271678X221135270
DO - https://doi.org/10.1177/0271678X221135270
M3 - Article
C2 - 36271598
SN - 0271-678X
JO - Journal of Cerebral Blood Flow and Metabolism
JF - Journal of Cerebral Blood Flow and Metabolism
ER -