Purpose : The purpose of this study was to assess the usefulness of CT angiography(CTA) with spiral CT in evaluation of intracranial vascular lesions.Materials and Methods : CTA and conventional angiography(CA) were performed in 22 patients with suspected intracranial vascualr lesion. Nine patients had 10 aneurysms and 2 patients had arteriovenous malformation(AVM)s, while the remaining 11 patients had no vascular lesion. Twenty seconds after beginning injection of contrast media(100mL with use of a power in jector at rate of 3mL/sec), CT scanning(30-second continuous exposure and 60-mm length) was performed with a table speed of 2mm/sec and a section thickness of 2mm. The starting point was selected at the floor of the sella turcica. The resulting data were reformatted by MIP and SSD after reconstruction of 1mm interval. For aneurysm, its size, shape, direction, neck and the relationship to adjacent vessels were compared to CA.Results : The aneurysm diameter was ranged between 3mm and 20mm and all aneurysmsa and the relationship between aneurysm and adjacent vessels were well correlated with CA. In one case of aneurysm, calcification of the aneurysm wall was demonstrated on CTA. In one case of AVM, the nidus and its arterial supply and venous drainage were well visualized. In the other case of AVM, however, the feeding artery of AVM was not demonstrated on CTA(it was also unclear on CA).Conclusion : CTA with CT may be useful in the evalustion of intracranial vascular lesion and valuable as a screening test for intracranial aneurysm.