Anatomical variations of anterior communicating artery

The Circle of Willis is a vascular network formed at the base of skull in the interpeduncular fossa. Its anterior part is formed by the anterior cerebral artery, from either side. Anterior communicating artery connects the right and left anterior cerebral arteries. Posteriorly, the basilar artery divides into right and left posterior cerebral arteries and each joins to ipsilateral internal carotid artery through a posterior communicating artery. Anterior communicating artery, an important component of circle of Willis, acts as collateral channel to stabilize blood flow. In the present study, anatomical variations in the anterior communicating artery were noted.

One hundred apparently normal formalin fixed brain specimens were collected from human cadavers. Normal anatomical pattern and variations of anterior communicating artery were studied. The anterior communicating arteries were then coloured, photographed, numbered and the abnormalities, if any, were noted.

Thity eight variant anterior communicating arteries were noted. The most common variation observed in the anterior communicating artery was its duplication in 10 subjects, followed by its absence in 8 subjects. Some variations like plexus formation, median artery were found in adults, because of persistence of embryonic pattern.

Knowledge on variations in the anterior communicating artery is of clinical significance, as it is one of the components of circle of Willis which stabilizes cerebral blood flow when principle conduits fail.