Abstract: To evaluate the 3D-digital subtraction angiography (DSA) and 2D-DSA in diagnosis of intracranial aneurysms. Method Both 3D-DSA and 2D-DSA were performed on 53 patients with subarachnoid hemorrhage(SAH) suspected as cerebra1 aneurysms by CT. Results In the 2D-DSA group, the accurate rate, positive rate, sensitivity and specificity were respectively 84.5% (49/58), 86.8%(46/53), 92%, and 81.8%. In the 3D-DSA group, the accurate rate and positive rate were 100%(58/58) and 94.3%(50/53), and the sensitivity and specificity were both 100%. By 2D-DSA, 23 cases of neck of aneurysm were clearly showed, and 22 cases were surely displayed the source vessel, however, by 3D-DSA, 58 cases of neck of aneurysm and 56 cases of source vessels were clearly showed, the difference between 2D- and 3D-DSA was significant（P＜0.05）. The mean radiation dose and contrastmedium of 2D-DSA were (178.32±17.39) mGy and (74.57±11.95)mL, while those of 3DDSA were (99.81±9.48) mGy and (54.15±7.05) mL, the difference between the two groups was also significant（P＜0.05）. Conclusions The neck of aneurysm and source vessel are more clearly in 3DDSA than in 2D-DSA,also the radiation and contrastmedium dose are much lower in 3D-DSA than in 2D-DSA.

Key words: Intracranial aneurysm, Imaging, threedimensional, Cerebral angiography