Original Research Noninvasive Magnetic Resonance Imaging Evaluation of Cerebral Blood Flow With Acetazolamide Challenge in Patients With

To evaluate the utility of using magnetic resonance imag-ing (MRI) of cerebral blood flow (CBF) in conjunction with pharmacologic flow augmentation, the authors imaged 14 patients with ischemic symptoms referable to large artery cerebrovascular stenosis of the anterior circulation. CBF was measured by using continuous arterial spin labeling (CASL) both at rest and 10 minutes after 1 g intravenous acetazolamide on a commercial 1.5 Tesla scanner. Quanti-tative CBF images were calculated along with augmenta-tion images showing the effects of acetazolamide. Interpret-able studies were obtained from all patients. Based on the image data as well as a region of interest analysis of CBF changes in middle cerebral artery distributions, varying patterns of augmentation were observed that suggested differing mechanisms of ischemic symptomatology. The ability to obtain this information in conjunction with a structural MRI examination extends the diagnostic poten-tial for MRI in cerebrovascular disease and allows the value of augmentation testing in clinical management to be assessed more widely. J. Magn. Reson. Imaging 1999;10