Abstract: Objective　To observe the origin、travel、and branch distribution of the anterior cerebral artery, which provides imaging basis for the diagnosis and treatment of cerebrovascular related diseases.　Methods　Brain Multilayer spiral CTA (MSCTA) imaging data of 100 patients without vascular disease were collected randomly, and the imaging anatomical structure of anterior cerebral artery was observed by using their own workstation for image post processing.　Results　(1) The values of each segment of the anterior cerebral artery were measured. There were statistical differences in length, inner diameter of segment A1 of the anterior cerebral artery, and the angle between A1 and A2 on the left and right sides. (2) The travel variation rate of the anterior cerebral artery was 20%,   in which the dominant sign of the left A1 segment was 9 %, while the right A1 segment was 5 %. The absence rate of A1 segment on the left side was 1 %, the dysplasia rate of bilateral anterior cerebral artery was 1 %, and the A4-A5 segment on the left side of compensatory blood supply was 1 %. The dominant sign of right A1 segment combined with ipsilateral A2-A5 segment stenosis (compensated blood supply by the left A2-A5 segment) was 1 %. 1 % of A4 segment and A5 segment joint stenosis, 1% of bilateral A1 segment malformation. (3) There were 71 % of the anterior cerebral artery with single trunk type, and 29 % with double trunk type.　Conclusions　MSCTA can display the full length and main branches of anterior cerebral artery and its anatomical variations in a clear and three-dimensional manner. The variation of anterior cerebral artery is complex and the difference between left and right sides is significant, which can provide a reliable basis for early detection and interventional treatment of clinical lesions.

Key words: Anterior cerebral artery, 　Spiral CT, 　3D reconstruction, 　Tomography anatomy