FUNCTIONAL MRI USING STEADY-STATE ARTERIAL WATER LABELING

Flow-sensitive functional MRI (fMRI) was performed using steady-state arterial water labeling (SS-AWL). Arterial water labeling was accompli shed by flow induced adiabatic fast passage. The signal intensity of t he visual cortex in arterial water labeled images decreased by similar to 1.4% during visual stimulation of the brain. Acquisition of arteri al water unlabeled and labeled images allows measurement of relative c erebral blood flow increase during brain activation. During visual sti mulation, cerebral blood flow in the visual cortex increased by 17 to 35% as measured by SS-AWL. Quantitation of brain activation in terms o f a physiological parameter using SS-AWL will facilitate comparative f MRI studies under different conditions.