Persistent primitive olfactory artery

A persistent primitive olfactory artery (PPOA) is a rare variant of the proximal anterior cerebral artery ^1,2. It is proposed to be more prone to aneurysms due to its sharp hairpin-like turn. Embryologically, the persistent primitive olfactory artery is the rostral division of the primitive internal carotid artery.

Gross anatomy

There are two variants of persistent primitive olfactory artery ¹:

• type 1
  • arises from the internal carotid artery
  • runs anteriorly along the olfactory tract
  • hairpin turn to supply the territory of the distal anterior cerebral artery
• type 2
  • arises from the anterior cerebral artery
  • passes through the cribriform plate to supply the nasal cavity as the ethmoidal artery