The Assessment Of The Usefulness Of 64 Detector Row Computed Tomographic Angiography(cta) In Identifyning And Evaluating Cerebral Anurysms Compared With Dsa

Objective:The aim of this study was to assess the usefulness of 64 detector row computed tomographic angiography(CTA) in identifyning and evaluating cerebral anurysms by comparing it with digital subtraction angiography(DSA) and partly with intraopreative findings.Methods:During a 27-month period(December 2007 and February 2010),54 patients with clinical suspected cerebral aneurysms were prospectively recruited to this study and underwent 64-detector CTA and DSA.47 of them who highly suspected cerebral aneurysms underwent cliping of anerurysms operation.We enrolled 54 consecutive patients (31 men,23 women), with a mean age of 54 years (rage 39-75),36 of them had subarachnoid haemorrhage,11 of them had worsening headache,6 of them had cerebral hemorrhage,1 of them had single oculomotor nerve palsy.64-detector CTA images analysis were performed interactively by the radiologist used various postprocessing techniques, mainly used volume rendering (VR) and maximum intensity projections (MIP). Using VR and MIP to show the shape, thrombus and calcification and parent vessel of aneurysm, comparing with DSA.Results:54 patients who were found 55 aneurysms by DSA, a total of 57 aneurysms were detected by CTA. The sensitivity, specificity and coincidence rate of CTA were 96.4%,70% and 92.4%. The positive predict value and negative predict value of MSCTA were 94.7% and 77.7%.7 patients who underwend DSA and CTA dected were negative. Two aneurysms located at the cavernous sinus of carotid artery and the vertebral artery were missing by CTA. Overall, CTA identified 57 aneurysms, the mean diameter was 6.4mm, the maximum was 18mm located at anterior communicating artery, the minimum was 1.7mm located at the left carotid artery. VR and MIP showed 6(10.5%) aneurysms whose diameter was under 2mm,4 (7%) aneurysms whose diameter was between 2mm and 3mm,39(68.4%) aneurysms whose diameter was between 3mm and 10mm,8(14%) aneurysms whose diameter was above 10mm. There is no difference in measuring aneurysms's neck and long diameter among VR, MIP and DSA (P>0.05). In addition, CTA was significantly superior to DSA in depicting aneurismal morphology and evaluating the branching pattern, neck geometry, and presence and extent of the aneurismal thrombus and clacification. The aneurysms and their surrounding structures were clearly demonstrated by MSCTA, and the finding of MSCTA was nearly coincidence with intraoperative observation.Conclusion:1. The sensitivity of the 64-CTA appears similar to DSA in detecting and evaluating intracranial aneurysms. To those aneurysms which are bigger than 2mm, the rate of VR, MIP and DSA had a great coincidence.There was no difference among VR and MIP and DSA in measuring aneurysms.2.The techniques of VR and MIP can better demonstrate the shape of aneurysms, the branching pattern, their surrounding structures and the calcification and thrombus of the aneurysms than DSA. To sum up,64 row-CTA has a highly sensitivity, accuracy and specificity in the assessment of the intracranial aneurysms.Compared to DSA, it also has an advantage of showing surrounding structures of aneurysms. MSCTA can be used as the first choice of screening and diagnosing intracranialan eurysms and it is very helpful in preoperative evaluation.