QUANTITATIVE MAGNETIC-RESONANCE-IMAGING OF HUMAN BRAIN PERFUSION AT 1.5-T USING STEADY-STATE INVERSION OF ARTERIAL WATER

We report our experience using a noninvasive magnetic resonance techni que for quantitative imaging of human brain perfusion at 1.5 T. This t echnique uses magnetically inverted arterial water as a freely diffusi ble blood flow tracer. A perfusion image is calculated from magnetic r esonance images acquired with and without arterial blood inversion and from an image of the apparent spin-lattice relaxation time. Single-sl ice perfusion maps were obtained from nine volunteers with approximate ly 1 x 2 x 5-mm resolution in an acquisition time of 15 min. Analysis yielded average perfusion rates of 93 +/- 16 ml.100 g-1.min-1 for gray matter, 38 +/- 10 ml.100 g-1.min-1 for white matter, and 52 +/- 8 ml. 100 g-1.min-1 for whole brain. Significant changes in perfusion were o bserved during hyperventilation and breath holding. This technique may be used for quantitative measurement of perfusion in human brain with out the risks and expense of methods which use exogenous tracers.