Figure 5. Digital subtraction angiography demonstrating an azygous variant of the ACA (red arrow) with a single midline ACA vessel distal to the anterior communicating artery (left). An aneurysm (red star) is arising proximal to the origin of the pericallosal artery. MRA demonstrating the Azygous ACA variant (red arrow) (right). An aneurysm is seen at the origin of the pericallosal arteries (red star).
