Background and importance: Some variations of the cerebral arterial circle of Willis, such as an inter-optic course of the anterior cerebral artery are exceedingly rare. Imaging of very rare anatomical features may be of interest.
Clinical presentation: In a 67-year-old male individual, the unique precommunicating part of the left anterior cerebral artery was found to course between both optic nerves. There was an agenesis of the right precommunicating cerebral artery. This variation was associated with an aberrant origin of the ophthalmic artery, arising from the anterior cerebral artery. The anatomic features, the possible high prevalence of associated aneurysms of the anterior communicating artery complex as well as implications for surgical planning or endovascular treatments are outlined and embryologic considerations are discussed.
Conclusion: To the best of our knowledge, this is a very rare illustrated case of an inter-optic course of a unique precommunicating anterior cerebral artery with aberrant origin of an ophthalmic artery.