Value of CT angiography in detection of cerebral artery aneurysms

Objective To evaluate the use of computed tomographic angiography (CTA) in the screening of cerebral aneurysms. Methods Twenty patients with unruptured cerebral aneurysms were examined by CT angiography and/or digital subtraction angiography (DSA). CTA was obtained using maximum intensity projection (MIP) reconstruction. 18 cases underwent surgery. The results were evaluated by DSA and the intraoperative findings. Results Of the 20 patients, a total of 21 aneurysms were detected by DSA and operation, and 20 aneurysms by CTA. 19 patients had 1 aneurysm, 1 patient had 2 (aneurysm of the posterior communicating artery were detected by DSA but not by CTA). The true positive diagnosis of aneurysms using CTA was 95% (20/21). Superselective MIP (or target reconstruction) and combined use of MIP image and source image were necessary for exact diagnosis. Conclusion We can diagnose unruptured cerebral aneurysm over 3.0 mm in size using CT angiography. CTA can be used in diagnosing, detecting , and following up of intracranial aneurysms. The sensitivity of three dimensional CTA is comparable with that of DSA, and it is simple, quick, noninvasive, reliable,and suitable for screening and diagnostic purposes.