Three-dimensional CT angiography in the evaluation of cerebral arteries in acute hemorrhage.

OBJECTIVE: We conducted this study to demonstrate the value of non-invasive three-dimensional CT angiography (3D CTA) in the detection of a cerebral aneurysm. MATERIAL AND METHODS: A helical CT acquisition was obtained using non-ionic contrast media in 50 patients with 1 mm per second table speed, 1 mm collimation, and pitch 1:1. Axial source images were transferred into a workstation console (Advantage windows GE) and CTA was obtained using MIP (Maximum Intensity Projection) reconstruction. Fourteen patients underwent conventional digital subtraction angiography (DSA) after 3D CTA prior to surgery. RESULTS: A total of 39 aneurysms were detected in 50 patients. All patients with an aneurysm were operated and the presence of aneurysms was confirmed. 3D CTA detected 38 of these 39 aneurysms. In 37 aneurysms, the origin of the aneurysm and aneurysm neck was adequately visualized. 3D CTA was found to be 100% specific and 97.2% sensitive in picking up cerebral aneurysms. 3D CTA was 97% specific in demonstrating the exact origin and showing the neck of the aneurysm. CONCLUSIONS: CT angiography is a simple, quick, and non-invasive technique and can replace DSA in most patients with acute subarachnoid hemorrhage aneurysm for the detection and characterization of aneurysms of the circle of Willis. The relation of the aneurysm with bony landmarks was clearly depicted.