title: Computerized tomography in subarachnoid hemorrhage: difference between patients with and without an aneurysm on angiography.
abstract: Fifty patients with spontaneous subarachnoid hemorrhage were investigated by both computerized tomography (CT), within 5 days of onset, and complete cerebral angiography. CT showed blood in the basal cisterns in 38 of the 42 patients with a demonstrable aneurysm, but in only 1 of 8 patients with a negative angiogram (p less than 0.001). This means that: (1) blood in the basal cisterns on CT almost certainly indicates a ruptured aneurysm, and (2) unexplained subarachnoid hemorrhages are unlikely to be caused by occult basal aneurysms.
mesh_terms: D002533:Cerebral Angiography; D003937:Diagnosis, Differential; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D012422:Rupture, Spontaneous; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed