Rapid quantitative CBF and CMRO2 measurements from a single PET scan with sequential administration of dual O-15-labeled tracers

: Kudomi N, Hirano Y, Koshino K, Hayashi T, Watabe H, Fukushima K, Moriwaki H, Teramoto N, Iihara K, Iida H

Publisher: NATURE PUBLISHING GROUP

: 2013

: Journal of Cerebral Blood Flow and Metabolism

: JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM

: J CEREBR BLOOD F MET

: 33

: 3

: 440

: 448

: 9

: 0271-678X

DOI: https://doi.org/10.1038/jcbfm.2012.188

Positron emission tomography (PET) with O-15 tracers provides essential information in patients with cerebral vascular disorders, such as cerebral blood flow (CBF), oxygen extraction fraction (OEF), and metabolic rate of oxygen (CMRO2). However, most of techniques require an additional (CO)-O-15 scan for compensating cerebral blood volume (CBV). We aimed to establish a technique to calculate all functional images only from a single dynamic PET scan, without losing accuracy or statistical certainties. The technique was an extension of previous dual-tracer autoradiography (DARG) approach, but based on the basis function method (DBFM), thus estimating all functional parametric images from a single session of dynamic scan acquired during the sequential administration of (H2O)-O-15 and O-15(2). Validity was tested on six monkeys by comparing global OEF by PET with those by arteriovenous blood sampling, and tested feasibility on young healthy subjects. The mean DBFM-derived global OEF was 0.57 +/- 0.06 in monkeys, in an agreement with that by the arteriovenous method (0.54 +/- 0.06). Image quality was similar and no significant differences were seen from DARG; 3.57%+/- 6.44% and 3.84%+/- 3.42% for CBF, and -2.79%+/- 11.2% and -6.68%+/- 10.5% for CMRO2. A simulation study demonstrated similar error propagation between DBFM and DARG. The DBFM method enables accurate assessment of CBF and CMRO2 without additional CBV scan within significantly shortened examination period, in clinical settings. Journal of Cerebral Blood Flow & Metabolism (2013) 33, 440-448; doi: 10.1038/jcbfm.2012.188; published online 12 December 2012