FIG 8.

Correlation between mCTA and CT perfusion imaging in a patient with left MCA M2 segment occlusion. A region of hypoattenuation in an arterial phase mCTA source image (A, circled area) closely correlates with a region of delayed Tmax in a CT perfusion image (B), suggestive of tissue at risk. Absence of hypoattenuation in a delayed venous phase mCTA source image (C) is matched by preservation of cerebral blood volume in a CT perfusion image (D), suggestive of no infarct core. The patient underwent endovascular intervention with restoration of TICI 2b antegrade flow. Subsequent diffusion-weighted MR imaging showed only small foci of acute ischemia in the frontoparietal region (not shown).