The CT findings in 19 cases of ruptured anterior communicating artery aneurysms are analyzed and compared to the angiographic appearance. Observations from this series and literature review include (a) occasional negative scans, (b) visualization of non-giant aneurysms on infused axial scans, (c) common asymmetric subarachnoid hemorrhage, (d) involvement of the anterior interhemispheric fissure whenever subarachnoid hemorrhage is visualized, (e) "typical" septal hematoma in a minority of cases, (f) frequent infarction, particularly in the anterior cerebral artery distribution, (g) "meningeal hyperemia" seen on post-contrast scans, and (h) little correlation between angiographic aneurysm orientation and the location of hemorrhage on CT scan.