目的探讨256层CT容积扫描在 头颈部CTA烟雾病诊断中的应用价值。方 法 21例患者行256层螺旋CT容积扫描诊断 为烟雾病，分析其CTA原始图像、后处理 重建图像特征。结果 21例烟雾病为单或 双侧颈内动脉终末段狭窄或闭塞，颅底均 有异常血管网，均发生在颅底Willis环附 近，17例丰富，4例较稀少；合并动脉瘤 发生率为14％(3/21)，其中1例为多发动 脉瘤。结论 256层CT容积扫描可清楚显示 颅底血管闭塞、狭窄、异常细血管网、动 脉瘤及侧支血管形成，可为烟雾病的诊断 和治疗提供重要资料。

Objective To evaluate the diagnostic value of 256-row volume CT in Moyamoya disease. Methods Twenty-one cases with Moyamoya disease were all scanned by 256-row volume CT, the original and reconstructed data was also evaluated. Results It was stenosis at the apices of the single or intracranial internal carotid arteries (ICA), including the proximal anterior cerebral arteries and middle cerebral arteries in all cases. Abnormal vascular net-work near Wills'circular at skull base, 17 cases of all had extensive abnormal basicranial vascular network, 4 cases fewer. 14%（3/21）accompanied by aneurysm, a case was multi-aneurysm. Conclusion 256-row volume CT can clearly show stenosis or occlusion of ICA, abnormal vascular network, aneurysm and collateral vessel of Moyamoya disease, and provid importantly information for the diagnosis and therapy．