CEREBRAL CT ANGIOGRAPHY IN THE DIAGNOSIS OF ACUTE SUBARACHNOID HEMORRHAGE

Purpose: To evaluate the usefulness of CT angiography (CTA) in the det ection of intracranial aneurysms in patients with acute subarachnoid h emorrhage (SAH).Material and Methods: In 53 patients with nontraumatic SAH a helical contrast-enhanced CTA was performed. CTA data were reco nstructed with maximum intensity projection (MIP). Each patient underw ent selective arteriography of the cerebral vessels (as the gold stand ard). CTA (axial images and MIP reconstructions) and arteriography wer e 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 demo nstrated a total of 51 aneurysms ranging in size from 3 mm to 16 mm. C TA missed one of these aneurysms, which was located at the internal ca rotid artery. 3-D CT reconstruction was slightly superior to arteriogr aphy in the demonstration of the neck, shape and direction of the aneu rysms. Partial thrombosis of 3 aneurysms was demonstrated only by CTA. Conclusion: Although CTA cannot replace cerebral arteriography in the diagnostic work-up of acute SAH, it proved to be helpful in demonstra ting the topographic anatomy of cerebral aneurysms and surrounding str uctures.