# Concomitance of Persistent Primitive Olfactory Artery and Basilar Artery Fenestration

## TL;DR

A 64-year-old woman was found to have two rare brain artery variations that could affect blood flow and surgical procedures.

## Contribution

This paper reports the first documented case of a persistent primitive olfactory artery coexisting with basilar artery fenestration.

## Key findings

- A persistent primitive olfactory artery was identified originating from the left anterior cerebral artery.
- A basilar artery fenestration was found with an anteroinferior cerebellar artery branching from the fenestrated segment.
- The coexistence of these two vascular anomalies is a unique observation with implications for diagnosis and treatment.

## Abstract

The cerebral arterial circle exhibits substantial morphological variability, occasionally encompassing rare congenital vascular variants. We report a unique case of a 64-year-old woman in whom computed tomography angiography (CTA) revealed the coexistence of a persistent primitive olfactory artery (PPOA) and basilar artery (BA) fenestration. The PPOA originated from the left anterior cerebral artery (ACA) and coursed anteroinferior toward the cribriform plate, where it formed a characteristic hairpin turn before resuming the typical A2 trajectory. Concurrently, a BA fenestration was identified, with the right anteroinferior cerebellar artery arising from the right limb of the fenestrated segment. The simultaneous occurrence of these two vascular morphological variants is a unique phenomenon. The recognition of such variations is critical, as both may alter cerebral hemodynamics, predispose to aneurysm formation, and complicate surgical or endovascular interventions. The awareness of these vascular variants is essential for accurate diagnosis and surgical planning. CTA and magnetic resonance angiography (MRA) remain reliable, non-invasive imaging modalities for the identification and characterization of these conditions.