【Objective】 To investigate the anatomical and clinical significance of 320-detector row CT angiography of the abnormal origin ophthalmic artery. 【Methods】 66 patients underwent 320-detector row CT angiography. The obtained thin-slice images were reformatted by using maximum intensity projection

curved planar reformation and volume rendering to evaluate ophthalmic artery. The origin and variation of the ophthalmic arteries were assessed. 【Results】 The ophthalmic artery of 120 sides arose from internal carotid artery

and respectively originated from the terminal

supraclinoid

siphonate

cavemous

petrous segment of internal carotid artery. 4 sides originated from the middle meningeal artery. The ability in detecting the ophthalmic artery origin by MPR

CPR

MIP and VR was near same

and the relation of the root of the ophthalmic artery and internal carotid arteries were shown well. 【Conclusion】 320-detector row CT angiography could accurately demonstrate the origin and variation of the ophthalmic artery

therefore it is helpful to provide anatomic basis for imaging diagnosis

interventional therapy and surgery by studying the anatomy of ophthalmic artery.