Abstract:Aim To explore the correlation between the initial origin stenotic segment of internal carotid artery and calcification score at siphon segment of internal carotid artery. Methods The CTA images of 216 patients were analyzed retrospectively. Calcification score at siphon segment in internal carotid artery was calculated using agatston’s method, all the cases were divided into calcification 0 score group, calcification 1~199 score group, calcification 200~399 score group, calcification 400~599 score group and calcification ≥600 score group. The initial origin stenotic segment of internal carotid artery was assessed based on North American Symptomatic Carotid Endarterectomy Trial. The relationship of calcification score at siphon segment of internal carotid artery were analyzed with initial origin stenotic segment of internal carotid artery. Results Two hundred and sixteen patients with 432 vascular were examined by CTA. Calcification at the siphon segment in internal carotid arteries had been found in 382. There were 70 vascular in calcification 1~199 score group, 100 vascular in calcification 200~399 score group, 112 vascular in calcification 400~599 score group and 100 vascular in calcification ≥600 score group. There were 18(25.7%), 78(78.0%), 106(94.6), 98(98.0%)vascular stenotic respectively in calcification 1~199 score group, in calcification 200~399 score group, in calcification 400~ 599 score group and in calcification ≥600 score group. Chi-square test statistical analysis showed that calcification score was significantly associated with initial origin stenotic segment of internal carotid artery stenotic (P<0.05). The initial origin stenotic segment of internal carotid artery was mild in calcification 0 score group and calcification 1~199 score group, mild-moderate in calcification 200~399 score group and mainly severe in calcification 400~599 score group and calcification ≥600 score group (P<0.05) . Spearman rank correlation analysis showed that the extent of internal origin stenotic segment of internal carotid artery were positively correlated with the calcification score at siphon segment of internal carotid artery (r=0.721, P<0.01). Conclusion With the growth of calcification score at the siphon segment in internal carotid arteries the probability of initial origin stenotic segment of internal carotid artery has increased. Detection of calcification score at the siphon segment in internal carotid arteries can be used as the effective basis of head and neck vascular stenosis lesions.