Values of 16-slice CTA and DSA in diagnosis of intracranial aneurysm

Objective To assess the values of 16-slice CTA and DSA in the diagnosis of intracranial aneurysms. Methods Eighty-two patients with SAH,suspected having aneurysms and admitted to our hospital from July 2007 to July 2008,received DSA and CTA;the clinical data of these patients were analyzed;CTA images were compared blindly with the DSA findings,including the presence,location,and size of aneurysms.With SPSS 11.5 statistical software,the sensitivity,specificity and accuracy of CTA and DSA were compared. Results Eighty-one aneurysms were detected by DSA and 74 aneurysms by CTA;no significant difirences on the positive detected rate were noted(x2=1.897,P=0.163).The sensitivity of CTA for detection of all aneurysms versus that of DSA was 91.4%,the specificity of CTA 91.7%.and the accuracy of CTA 91.4%.Sixty-five patients underwent surgery (clipping)and 73 aneurysms were confirmed by this surgery;CTA had a sensitivity of 89.0%,specificity of 100%and accuracy of 90.5%:DSA had a sensitivity of 98.6%,specificity of 84.6%and accuracy of 98.8%;significant statistical diference on sensitivity (x2=5.625,P 0.05)were found between them.As compared with the sizes of aneurysms and the diameters of aneurysm necks measured during the operation,these results detected by CTA were significantly larger(P<0.05).CTA had different detection sensitivities to aneurysms at different locations and with different sizes,while DSA had high sensitivity.Conclusion CTA is a noninvasive, quick, sensitive and efficient tool to diagnose inrtacranial aneurysms.It can be specially used to screen aneurysms in SAH patients.In some cases,CTA can guide the surgery. Key words: Subarachnoid-hemorrhage; Intracranial aneurysm;  CTA; DSA