The acetazolamide challenge: imaging techniques designed to evaluate cerebral blood flow reserve

AJR Am J Roentgenol. 1989 Sep;153(3):605-12. doi: 10.2214/ajr.153.3.605.


Cerebral blood flow was analyzed by the stable xenon (Xe)/CT scanning technique in 29 patients with significant vascular lesions before and after administration of an acetazolamide (Diamox) vasodilatory challenge. Three response types were identified: I, normal flow before Diamox with flow augmentation after Diamox; II, low flow before Diamox with flow augmentation after Diamox; and III, low or normal flow before Diamox with no augmentation or decreased flow after Diamox. Twenty-four percent of the patients studied qualified for category III. We believe that patients in this category represent a group of individuals without blood flow reserve whose clinical management should include careful consideration of their hemodynamic status. The Xe/CT scanning technique with the addition of Diamox flow challenge is a clinically accessible and effective method for assessing cerebral blood flow and blood flow reserve.

Publication types

  • Case Reports

MeSH terms

  • Acetazolamide*
  • Adult
  • Aged
  • Cerebrovascular Circulation*
  • Cerebrovascular Disorders / diagnostic imaging*
  • Cerebrovascular Disorders / physiopathology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Tomography, X-Ray Computed / methods
  • Xenon


  • Xenon
  • Acetazolamide