Infundibulum of Accessory Anterior Cerebral Artery: Rare, Likely Benign Malformation of Anterior Communicating Artery Complex to Keep in Mind.

Background: Infundibular dilations (IDs) are funnel-shaped enlargements located at the origin of cerebral arteries. Neuroradiologists and neurosurgeons are familiar with IDs of the posterior communicating artery, which are relatively common. Other locations, being unexpected sites of IDs, can pose diagnostic and therapeutic challenges.

Case Description: In this paper, we describe a case of infundibulum of the accessory anterior cerebral artery, diagnosed with 3-dimensional reconstructions of computed tomography angiography, which is to our knowledge the first report of an ID of this anatomic variant.

Conclusions: Anterior communicating artery represents a rare location for infundibular dilations. Differential diagnosis between them and true aneurysms can be sometimes challenging, especially when associated with anatomic variants; thus neurosurgeons and radiologists must be aware of these pathologic entities.