Basilar artery formed by persistent primitive trigeminal artery: a case report

Area of Science:

• Neurology
• Vascular Anatomy
• Embryology

Background:

• Persistent primitive trigeminal artery (PPTA) is an embryological variation with a prevalence of 0.1-0.6%.
• Typically, PPTA connects to the proximal basilar artery (BA), supplying cerebellar arteries.
• Variations in PPTA's role in cerebral circulation are infrequently reported.

Observation:

• A unique case diagnosed via digital subtraction angiography (DSA) is presented.
• The vertebral artery (VA) terminated in the posterior inferior cerebellar artery (PICA).
• The PPTA exclusively formed the basilar artery (BA), supplying the entire posterior circulation.

Findings:

• This is the first reported instance of PPTA being the sole source for the basilar artery.
• The anatomical configuration demonstrated a complete absence of typical BA formation from vertebral arteries.
• The PPTA provided comprehensive blood supply to the posterior cerebral circulation.

Implications:

• This case expands the understanding of PPTA's anatomical variations and its potential role in cerebrovascular development.
• Highlights the importance of advanced imaging like DSA in diagnosing rare vascular anomalies.
• Contributes to the literature on atypical posterior circulation anatomy, crucial for neurosurgical and interventional procedures.