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PT  - JOURNAL ARTICLE
AU  - Vagal, A.S.
AU  - Leach, J.L.
AU  - Fernandez-Ulloa, M.
AU  - Zuccarello, M.
TI  - The Acetazolamide Challenge: Techniques and Applications in the Evaluation of Chronic Cerebral Ischemia
AID  - 10.3174/ajnr.A1538
DP  - 2009 May 01
TA  - American Journal of Neuroradiology
PG  - 876--884
VI  - 30
IP  - 5
4099  - http://www.ajnr.org/content/30/5/876.short
4100  - http://www.ajnr.org/content/30/5/876.full
SO  - Am. J. Neuroradiol.2009 May 01; 30
AB  - SUMMARY: The acetazolamide (ACZ) challenge test is a useful clinical tool and a reliable predictor of critically reduced perfusion. In patients with chronic steno-occlusive disease, the ability to maintain normal cerebral blood flow by reducing vascular resistance secondary to autoregulatory vasodilation is compromised. Identification of the presence and degree of autoregulatory vasodilation (reflecting the cerebrovascular reserve) is a significant prognostic factor in patients with chronic cerebrovascular disease. The pharmacologic challenge of a vasodilatory stimulus such as ACZ can also be used to optimize the treatment strategies for these patients. The pathophysiology, methods, and clinical applications of the ACZ challenge test are discussed in this article.