title: Cerebral CT angiography in the diagnosis of acute subarachnoid hemorrhage.
abstract: OBJECTIVE
  To evaluate the usefulness of CT angiography (CTA) in the detection of intracranial aneurysms in patients with acute subarachnoid hemorrhage (SAH).
  
  
  METHODS
  In 53 patients with nontraumatic SAH a helical contrast-enhanced CTA was performed. CTA data were reconstructed with maximum intensity projection (MIP). Each patient underwent selective arteriography of the cerebral vessels (as the gold standard). CTA (axial images and MIP reconstructions) and arteriography were evaluated separately and their diagnostic information was compared.
  
  
  RESULTS
  In 14 of the 53 patients neither CTA nor angiography showed a vascular malformation. In the remaining 39 patients, angiography demonstrated a total of 51 aneurysms ranging in size from 3 mm to 16 mm. CTA missed one of these aneurysms, which was located at the internal carotid artery. 3-D CT reconstruction was slightly superior to arteriography in the demonstration of the neck, shape and direction of the aneurysms. Partial thrombosis of 3 aneurysms was demonstrated only by CTA.
  
  
  CONCLUSIONS
  Although CTA cannot replace cerebral arteriography in the diagnostic work-up of acute SAH, it proved to be helpful in demonstrating the topographic anatomy of cerebral aneurysms and surrounding structures.
authors.affiliation: Department of Radiology, University of Regensburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Lenhart
authors.forename: T
authors.initials: T
authors.lastname: Bretschneider
authors.forename: J
authors.initials: J
authors.lastname: Gmeinwieser
authors.forename: O W
authors.initials: OW
authors.lastname: Ullrich
authors.forename: J
authors.initials: J
authors.lastname: Schlaier
authors.forename: S
authors.initials: S
authors.lastname: Feuerbach
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000150:complications / Q000000981:diagnostic imaging; D015901:Angiography, Digital Subtraction / Q000295:instrumentation / Q000379:methods; D001921:Brain / Q000000981:diagnostic imaging*; D002533:Cerebral Angiography / Q000295:instrumentation / Q000379:methods*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012422:Rupture, Spontaneous; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*