Comparison of cerebral blood flow measurement with [¹⁵O]-water positron emission tomography and arterial spin labeling magnetic resonance imaging: A systematic review

Abstract

Noninvasive imaging of cerebral blood flow provides critical information to understand normal brain physiology as well as to identify and manage patients with neurological disorders. To date, the reference standard for cerebral blood flow measurements is considered to be positron emission tomography using injection of the [(15)O]-water radiotracer. Although [(15)O]-water has been used to study brain perfusion under normal and pathological conditions, it is not widely used in clinical settings due to the need for an on-site cyclotron, the invasive nature of arterial blood sampling, and experimental complexity. As an alternative, arterial spin labeling is a promising magnetic resonance imaging technique that magnetically labels arterial blood as it flows into the brain to map cerebral blood flow. As arterial spin labeling becomes more widely adopted in research and clinical settings, efforts have sought to standardize the method and validate its cerebral blood flow values against positron emission tomography-based cerebral blood flow measurements. The purpose of this work is to critically review studies that performed both [(15)O]-water positron emission tomography and arterial spin labeling to measure brain perfusion, with the aim of better understanding the accuracy and reproducibility of arterial spin labeling relative to the positron emission tomography reference standard.

Higher Aortic Stiffness Is Associated With Lower Global Cerebrovascular Reserve Among Older Humans

“…45,49,50 In addition, the present study induced maximal dilation using the carbonic anhydrase inhibitor, ACZ, to determine CVR. This is important because recent studies demonstrated that the reactivity to a hypercapnic stimulus may be altered in individuals with higher fitness 51 while ACZ reliably produces maximal dilation in humans.…”

“…15 O]water PET imaging 49 along with regional and brain matter differences in the CBF estimates between methods. 45,49,50 In addition, the present study induced maximal dilation using the carbonic anhydrase inhibitor, ACZ, to determine CVR.…”

Pseudo continuous arterial spin labeling quantification in anemic subjects with hyperemic cerebral blood flow

“…Greater than 75% of variance in the PC CBF could be explained by inter-patient variations in oxygen content, grey matter volume and patient age, which are all known CBF determinants(6,24). While some studies suggest excellent agreement between PCASL CBF and O-15 H 2 O positron emission tomography CBF measurements in normal adults(49,50), comparable studies have not been performed in patients with chronic anemia syndromes.…”

Test-retest reliability of cerebral blood flow in healthy individuals using arterial spin labeling: Findings from the EMBARC study

“…Unlike positron emission tomography (PET) and single-photon emission computed tomography (SPECT), which require radioligands, ASL uses an endogenous marker that allows repeated use without radiation exposure [1]. Importantly, ASL shows high concordance with these more invasive neuroimaging techniques [2–4]. For example, resting CBF measures in cortical regions acquired with ASL and H 2 O PET were similar in healthy subjects [3].…”