烟雾病颅脑磁共振影像学诊断特征分析

Magnetic resonance imaging characteristics of moyamoya disease

目的探讨烟雾病患者颅脑磁共振成像(MRI)平扫及磁共振血管造影(MRA)影像学特点。方法回顾性分析2014年10月至2019年3月丰县人民医院神经内外科及儿科收治的资料完整的25例烟雾病患者的临床及影像学资料。所有患者均行常规1.5T轴位T1WI、T2WI、液体衰减反转恢复(FLAIR)、弥散加权(DWI)及矢状位T2WI序列扫描,同时行三维—时间飞跃(3D-TOF)法MRA扫描;病程中患者均有CT平扫资料,15例有CT血管造影(CTA)资料,12例有数字减影血管造影(DSA)资料。结果MRI平扫均可显示双侧颈内动脉末端、大脑中动脉及大脑前动脉变细、流空差,颅底中线两旁区域出现烟雾状流空信号影,以轴位T2WI显示最佳;FLAIR见两侧大脑半球沿软脑膜分布的点状或条状高信号(“常春藤征”),以额顶叶为多;21例患者的T2WI及FLAIR还可见放射冠、半卵圆中心白质区呈现垂直于侧脑室壁的刷子状高信号(“刷子征”),20例T2WI可见基底节区血管流空信号影。MRI诊断25例脑梗死(伴新鲜梗死灶6例),陈旧性出血9例。MRA可显示双侧颈内动脉末端、大脑中动脉及大脑前动脉不同程度狭窄或闭塞、颅底异常血管网形成,TOF源图像均可见两侧基底节区高信号强度区域。结论MRI及MRA可显示烟雾病特征性的血管狭窄、侧支循环征象及所造成的卒中等不良结果,值得应用。

Objective To explore the characteristics of brain magnetic resonance imaging(MRI)and magnetic resonance angiography(MRA)in moyamoya disease.Methods The clinical and imaging data of 25 patients with moyamoya disease(MMD)from October 2014 to March 2019 in the Department of Pediatric,Neurology and Neurosurgery in Fengxian People's Hospital were retrospectively analyzed.These patients underwent conventional 1.5 T MR with axial T1WI,T2WI,FLAIR,DWI,sagittal T2WI and 3D-TOF MRA.During the course of disease,all patients underwent CT plain scan,15 patients underwent CT angiography(CTA)and 12 patients underwent digital subtraction angiography(DSA).Results MRI plain scan showed that the bilateral internal carotid artery ends,middle cerebral artery and anterior cerebral artery were thinned and the flow void was poor.The flow void signal of moyamoya vessels appeared on both sides of the skull base midline,which showed the best on axial T2WI.Point or strip-like high signal(ivy sign)distributed along the pia mater in both sides of the cerebral hemisphere on FLAIR images,mostly in the frontal and parietal lobes.Brush-like hyperintense signal(brush sign)on T2WI and FLAIR images could be seen in the radiation crown and semi-oval in 21 patients.Flow void of the basal ganglia could be seen on T2WI in 20 patients.Twenty-five patients with cerebral infarction(6 cases with fresh infarction)and 9 cases with old hemorrhage were diagnosed by MRI.MRA clearly showed different degrees of stenosis or occlusion in the end of bilateral internal carotid artery,anterior-middle cerebral artery and the abnormal vascular network at the skull base and high signal intensity areas of the bilateral basal ganglia on TOF source images.Conclusion MRI and MRA can show the characteristic vascular stenosis of moyamoya disease,its collateral circulation signs and the adverse results of stroke caused by moyamoya disease,which are worthy of application.