Presentation
Presenting with new confusion, chest pain and visual changes.
Patient Data
Age: 70-80 years
Gender: Male
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A linear density involves the left PCA. There is no area of hypodensity to indicate established infarct.
Arterial phase CT head
From the case:
Ischemic stroke - dense posterior cerebral artery (PCA) sign
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The left PCA is not seen. The vessel is occluded at its origin.
Case Discussion
A dense vessel on unenhanced CT is an insensitive but specific sign in acute ischemic stroke.
It is important to evaulate the thin slices for a dense vessel, as this finding may be missed on 3 mm slices.
Complete absence of the left P1 on arterial phase imaging indicates that the thrombus extends to its origin.