Fig. 1. Common aneurysm sites in lateral (A) and basal (B) views. Numbers indicate percentage of aneurysms in each location. ACoA, anterior communicating artery; MCA, middle cerebral artery; ICA, internal carotid artery; PCoA, posterior communicating artery; PCA, posterior cerebral artery; VA, vertebral artery; BA, basilar artery. (Data from Krayenbuhl O: Kassifikation and Klinische Symptomatologie der zerebralen Aneurysmen. Ophthalmologica 167:122, 1973).