A comparison of OEF mapping in aging by using different arterial spin labeling method based on QSM+qBOLD

Motivation: Age-related changes in hemodynamic parameters may influence the accuracy of the oxygen extraction fraction (OEF) mapping by the original QSM+qBOLD (QQ) model. Goal(s): We aimed to apply multi-delay ASL in the QQ model to improve the accuracy of OEF quantification during aging. Approach: The impact of using single- and multi-delay ASL methods across age groups was investigated in 65 healthy volunteers aged 18-75 years. Results: The OEF estimate with multi-delay ASL was significantly higher than with single-delay ASL in the older group (P<0.05). The whole brain bias of OEF (r = 0.310, P = 0.013) also showed a positive correlation with age. Impact: The QQ with multi-delay ASL method may improve OEF quantification caused by haemodynamic variations with ageing, such as arterial transit time (ATT), and may be useful for studying oxygen metabolism in patients with cerebrovascular disease.