Three-dimensional CT angiography and surgical correlation in the evaluation of intracranial aneurysms.

OBJECTIVE: To evaluate the diagnostic accuracy of three-dimensional CT angiography in the surgical treatment of intracranial aneurysms. METHODS: Twenty-four patients suspected of intracranial aneurysms underwent routine catheter four-vessel angiography, three dimensional CT angiography (3D-CTA), magnetic resonance angiography (MRA) or conventional digital subtraction angiography (DSA). RESULTS: A total of 28 aneurysms were detected by CT angiography in this study. Twenty-one patients each had a single aneurysm, two patients each had two aneurysms, and one had three aneurysms. The shapes of aneurysms revealed by 3D-CTA were round in 20 lesions, elliptical in 5, and 1 obulated in 3. Of the 24 lesions which were completely disclosed during surgery, the shapes correlated well with the 3D-CT angiograms. The mean diameter of the aneurysmal neck was 5.9 mm in 3D-CTA images, with the smallest being 1.6 mm and the largest 13.7 mm. The size was very close to the actual size measured at surgery (P < 0.001), revealing that 3D-CT angiograms correlated well with surgical findings. Compared with images obtained by routine catheter four-vessel angiography, MRA and DSA, 3D-CTA images depicted the relationship of aneurysms to parent vessels and other branches more clearly. CONCLUSION: 3D-CTA enables surgeons to understand the 3D structure of intracranial aneurysms and is very useful in planning the surgical treatment of cerebral aneurysms.