Artery of percheron: anatomical variations, clinical relevance, and neurosurgical applications

Abstract

The artery of Percheron (AOP) is a rare anatomical variant where a single perforating arterial trunk originates from the P1 segment of the posterior cerebral artery and supplies the bilateral paramedian thalami and rostral midbrain. Its variability and underrepresentation in canonical anatomical texts are clinically relevant to neurosurgical and neurovascular practice. This review aims to summarize the current evidence regarding its anatomical variants, imaging features, clinical significance and neurosurgical implications. We conducted a narrative review of the literature in PubMed, Scopus, and Google Scholar (2000–2024). This narrative review employed a transparent and structured literature search strategy; however, no formal risk-of-bias assessment, PRISMA-based protocol, or meta-analytic statistical synthesis was undertaken, consistent with the narrative design of this work. The most common origin of AOP is the P1 segment (corresponds to the Type IIB perforator pattern) supplying bilateral paramedian thalami and often the midbrain. Isolated bilateral thalamic and combined thalamic–midbrain infarction patterns have been described using MRI diffusion-weighted imaging, which has nearly complete diagnostic sensitivity. A characteristic midbrain “V sign” was observed in half of the cases with midbrain involvement. Clinically, AOP occlusion is characterized by altered consciousness, vertical gaze palsy, and memory impairment. Etiologies included small-vessel disease, large-vessel disease, cardioembolism (0–22%), and idiopathic causes. The AOP is also important in skull base, endoscopic, and vascular neurosurgery where accidental injury can lead to bilateral thalamic infarction. AOP occlusion is a rare but significant cause of bilateral thalamic stroke. Improved outcome and avoidance of iatrogenic injury in neurosurgical practice depend on the early recognition of MRI and its anatomic variability.