Simultaneous Imaging of Absolute CBF Change and BOLD with Saturation-Recovery-T1 MRI Approach Under Ischemia and Hypercapnia

Xiao Wang¹, Xiao hong Zhu¹, Yi Zhang¹, Wei Chen¹

Apparent T1 is sensitive to cerebral perfusion, thus, CBF can be imaged by MR-based arterial spin labeling techniques. In this study, we proposed an alternative approach based on the saturation-recovery T1 imaging method for simultaneously measuring absolute CBF change (∆CBF) and BOLD. This perfusion approach was validated by examining the relationship between the simultaneously-measured CBF using the MRI approach and relative percent CBF change using LDF in the rat brain under ischemia and hypercapnia conditions. The results suggest that the measured change in apparent T1 was tightly correlated to the absolute CBF increase during hypercapnia and decrease during ischemia. This perfusion approach, thus, should provide a useful, robust MRI tool for noninvasively imaging absolute CBF change and BOLD associated with brain physiology, function and viability.