A 34-year-old man with severe headache and blurry vision was diagnosed with Moyamoya disease. A 34-year-old man with severe headache and blurry vision was diagnosed with Moyamoya disease. CT perfusion maps. A, Baseline. B, After ACZ administration. CBF (measured in mL/100 g/min) is diminished in bilateral ACA, ACA-MCA watershed, and the MCA territories (depicted as blue to green). These areas show a very suboptimal increase in CBF after ACZ administration and thus exhibit limited CVR. Note the increased CBF secondary to vasodilatory capacity in the PCA and MCA-PCA distribution after ACZ administration. A.S. Vagal et al. AJNR Am J Neuroradiol 2009;30:876-884 ©2009 by American Society of Neuroradiology