颈内动脉发育不良的CT诊断

MDCT Detection of Hypoplasia of the Internal Carotid Artery

目的探讨颈内动脉发育不良的CT特点。方法搜集经影像学诊断的4例颈内动脉发育不良患者,复习相关文献,分析其CT特点。结果 4例颈内动脉发育不良均为单侧,左、右侧各2例;均显示患侧相对纤细的颈总动脉、线样狭窄的颈内动脉部分节段及细小的颈动脉管。1例颈内动脉全程线样狭窄,止于眼动脉,另3例颈内动脉呈节段性线样狭窄;其中1例颈内动脉起始部至C6线样狭窄,C7正常; 2例为颈内动脉起始部相对正常,分叉以上约10 mm以远管腔呈线样弥漫狭窄,其中1例C4～7段管腔正常; 2例显示明确的侧支血管,1例同时合并颅内多发动脉瘤;另2例侧支血管显示不明显,患侧大脑中动脉纤细或闭塞,其中1例颅脑CT灌注未见异常灌注区。4例颈外动脉及分支、椎-基底动脉均未见异常。结论颈内动脉先天发育不良累及颈内动脉的部分节段或全程,诊断需要结合颈内动脉管壁、管腔及颈动脉管的形态,CT可以满足诊断要求,为首选影像学检查。

Objective To analyze CT manifestations of congenital hypoplasia of the internal carotid artery( ICA) in order to highlight the awareness of this disease. Methods The CT manifestations were retrospectively analyzed in 4 cases of congenital hypoplasia of the ICA. The related literatures were reviewed. Results 4 cases presented with unilateral ICA anomalies,showing slightly diminutive common carotid artery( CCA),significantly uniform narrowing ICA without intraluminal lesions and homolateral diminutive bony carotid canal in the base of skull on the affected side. One case showed ICA hypoplasia along its entire course terminating as the ophthalmic artery with no contribution to cerebral vasculature. 2 cases showed ICA hypoplastic from 10 mm above the carotid bifurcation,among which one terminating at C4 portion. In the fourth case,the hypoplastic ICA terminated at the C6 portion. However,the external carotid arteries and their branches of the 4 cases were normal. The collateral vessels were well established in 2 cases,multiple intracranial aneurysms were detected in one patient. Perfusion CT was done in 1 case without significant collateral vessels,revealing no evident defect in cerebral perfusion. Conclusion Diagnosis of ICA hypoplasia was based on the morphology of CCA,ICA and bony carotid canal. CT imaging can depict the characteristic findings,which is of great value to establish the diagnosis.