Presentation
Acute dizziness: to rule out an acute stroke
Patient Data
Age: 40 years
Gender: Male
From the case:
A1 segment hypoplasia
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Hypoplastic A1 segment of the left anterior cerebral artery.
Both posterior communicating arteries are hypoplastic.
Otherwise, the circle of Willis appears unremarkable.
From the case:
A1 segment hypoplasia
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Hypoplastic A1 segment of the left anterior cerebral artery (yellow arrow).
Both posterior communicating arteries are hypoplastic.
Otherwise, the circle of Willis appears unremarkable.
Case Discussion
Anterior cerebral artery A1 segment hypoplasia is an uncommon fetal variant of the circle of Willis. The frequency of this congenital variation is 1–13% as derived from angiograms and autopsy reports 1.
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