Detection and assessment of intracranial aneurysms: value of CT angiography with shaded-surface display.

Abstract

We were able to detect aneurysms of the circle of Willis as small as 2 mm in size. Using conventional angiography as the reference standard, CT angiography has a sensitivity of 88% and a specificity of 89% for the detection of aneurysms in the circle of Willis. In almost all cases, CT angiography was equal or superior to conventional angiography in characterizing the aneurysms for surgical planning.