Persistent Hypoglossal Artery

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Large Persistent Hypoglossal Artery (PHA) is seen traversing the hypoglossal canal.

Note origin of this large vessel (Persistent Hypoglossal Artery marked with arrow) that is from distal Internal Carotid Artery (ICA) (arrow head) and located posteriorly to it.

3D reconstructions with mandible partially removed show PHA (arrow) as a large vessel posterior to ICA. Also note how it feeds the basilar artery after exiting from the hypoglossal canal. This case is very interesting not only due to persistent vessel but also that PHA is the only feeding vessel for the basilar artery since both vertebral arteries are hypoplastic and there are no posterior communicating arteries.

Interesting article form RadioGraphics:
Normal Variants of the Cerebral Circulation at Multidetector CT Angiography - Simon J. Dimmick

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