Clinical Value Of Diagnosing Intracrnial Aneurysmswith Fly-around Of Multislice Helical

Objective: To evaluate the application value of the multislice CT(MSCT)fly-around technique in the diagnosings of intracranial aneurysms.Methods : MSCT three dimensional angiography (MS-3D-CTA) were performed in 30 patients with suspected intracranial aneurysms. Fly-around shaded volume remdering(SVR) and maximal intensity projection(MIP) were used in 3D post-processing technique. The post-processing images were compared with digital substraction angiography (DSA) and surgery. The post-processing images and DSA were analyzed and evaluated by 2 radiologists at double blinded. The parameters of scanning and images reconstructing were: slice thickness 2.0mm, helical pitch 3.5mm, interval of reconstruction was 1.0mm, delay time was 12-20s; Nonionic contrast medium was injected intravenously (total 60~100ml) at speed of 3.0ml/s. Of 30patients 17 patients accepted the DSA examination, 9patients were proved by surgery. Results: (1)16 intracranial aneurysms were proved at DSA and surgery , all patients presented as a solitary lesion, the largest aneurysm was12.0mm in diameter and the smallest aneurysm was 3.0mm in diameter. Fly-around s SVR> MIP and DSA all found out 16 aneurysms, positive findings 100%. The neck of fifteen aneurysms could be clear shown in fly-around, the neck of ten aneurysms could be clear shown in DSA. The original artery of fourteen aneurysms could be clear revealed, the original artery of eleven aneurysms could be clear revealed.(2)SVR is superior to DSA in observing throughout willis and the vessels around willis, and it is useful to select a target vessel to perfusion.(3)MIP is superior to DSA in finding the calification of vessel wall.Conclusion: MSCT angiography is a rapids simples safe and no-injured graphic method of blood pipe. It can reach as same results as DSA in finding aneurysms around the willis over 3.0mm in diameter, fly-around is superior to DSA in finding the neck of aneurysm and original artery of aneurysm. Fly-around in combination with SVR and MIP technique are very helpful to diagnose intracranial aneurysms, and can provide important for surgery in operative paths.