Gadolinium-DTPA has been shown to be a good probe for demonstrating defects in the blood-brain barrier, but it has a rapid rate of elimination so that peak circulating levels are short-lived. In this study ultrafast echo-planar imaging has been used in combination with a bolus injection of gadolinium-DTPA to evaluate perfusion within brain tumors and to assess the degree of disruption of the blood-brain barrier. The temporal profile of enhancement may allow discrimination between different tumor types.