Transfer function analysis assesses resting cerebral perfusion metrics using hypoxia-induced deoxyhemoglobin as a contrast agent

Frontiers in Physiology

Physiology

James Duffin¹  Ece Su Sayin¹  Joseph A. Fisher²  Olivia Sobczyk³  David J. Mikulis⁴  Julien Poublanc⁴ 

[1] Department of Physiology, University of Toronto, Toronto, ON, Canada;Departments of Anaesthesia and Pain Management, University Health Network, Toronto, ON, Canada;Department of Physiology, University of Toronto, Toronto, ON, Canada;Departments of Anaesthesia and Pain Management, University Health Network, Toronto, ON, Canada;Toronto General Hospital Research Institute, University Health Network, University of Toronto, Toronto, ON, Canada;Departments of Anaesthesia and Pain Management, University Health Network, Toronto, ON, Canada;Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, ON, Canada;Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory, University Health Network, Toronto, ON, Canada;

关键词: transfer function analysis;    transient hypoxia;    MRI;    BOLD = blood oxygen level dependent;    contrast agents;    brain;    perfusion imaging;   

DOI  :  10.3389/fphys.2023.1167857

 received in 2023-02-16, accepted in 2023-04-07,  发布年份 2023

来源: Frontiers

【 摘 要 】

Introduction: Use of contrast in determining hemodynamic measures requires the deconvolution of an arterial input function (AIF) selected over a voxel in the middle cerebral artery to calculate voxel wise perfusion metrics. Transfer function analysis (TFA) offers an alternative analytic approach that does not require identifying an AIF. We hypothesised that TFA metrics Gain, Lag, and their ratio, Gain/Lag, correspond to conventional AIF resting perfusion metrics relative cerebral blood volume (rCBV), mean transit time (MTT) and relative cerebral blood flow (rCBF), respectively.Methods: 24 healthy participants (17 M) and 1 patient with steno-occlusive disease were recruited. We used non-invasive transient hypoxia-induced deoxyhemoglobin as an MRI contrast. TFA and conventional AIF analyses were used to calculate averages of whole brain and smaller regions of interest.Results: Maps of these average metrics had colour scales adjusted to enhance contrast and identify areas of high congruence. Regional gray matter/white matter (GM/WM) ratios for MTT and Lag, rCBF and Gain/Lag, and rCBV and Gain were compared. The GM/WM ratios were greater for TFA metrics compared to those from AIF analysis indicating an improved regional discrimination.Discussion: Resting perfusion measures generated by The BOLD analysis resulting from a transient hypoxia induced variations in deoxyhemoglobin analyzed by TFA are congruent with those analyzed by conventional AIF analysis.

【 授权许可】

Unknown   
Copyright © 2023 Sayin, Sobczyk, Poublanc, Mikulis, Fisher and Duffin.