The limitations of three-dimensional CT angiography (3D-CTA) in the diagnosis of cerebral aneurysms

Object: The purpose of this study is to show some limitations of 3D-CTA to diagnose cerebral aneurysms. Methods: Sixteen saccular aneurysms less than 10mm in diameter were included. Large and complicated aneurysms were excluded. Results: Although information about perforating arteries from the posterior cerebral artery is very important for sugery of basilar bifurcation aneurysms, 3D-CTA could not delineate the perforating arteries. A small posteior communicating artery (Pcom.A.) was not detected, and it was very difficult to differentiate infundibular dilatation of the Pcom. A. from an aneurysm. A small aneurysm of the distal middle cerebral artery could not be detected. Flow direction can not be determined by 3D-CTA, and nor could the side of the neck of the anterior communicating artery aneurysm be determined. Fenestration of the anterior communicating artery and the origin of the triple anterior cerebral artery were both misdiagnosed as anterior communicating artery aneurysms. Conclusion: It is premature to consider 3D-CTA as a replacement for conventional angiography.