3.0T HRMRI头颈联合技术对症状性MCA狭窄患者颅内外动脉管壁病变的诊断价值

摘要

Objective To investigate the intra-and extracranial arterial wall abnormality in patients with symptomatic middle cerebral arterial(MCA)stenosis and clinical value of 3.0T High-resolution magnetic resonance imaging(HRMRI)of simultaneous carotid and intracranial vessel wall.Method Eleven patients with symptomatic MCA stenosis underwent three dimensional contrast-enhanced MRA(3D ce-MRA)and 3.0T HRMRI.3.0T HRMRI included precontrast and post-contrast T1-db SPACE,and was combined with simultaneous carotid and intracranial vessel wall imaging.Result Eighty-eight vessel walls of 11 patients indicated:one patient had central nervous system vasculitis with concentric thickening and enhancement of left MCA and internal carotid artery(ICA)on T1-db SPACE;one had intracranial arterial dissection with long-striped hyper-intensity of left MCA on T1-db SPACE and iso-intensity and hypo-intensity of left MCA on T2-db SPACE;nine had atherosclerosis with bilateral MCA atherosclerotic plaques manifested as eccentric thickened wall,eight out of 9 patients had both intra-and extracranial atherosclerotic plaques,and 6(67%)patients' intra-and extracranial atherosclerotic plaques were enhanced simultaneously.Comparison of 3D ce-MRA and HRMRI showed 23 vessel walls were normal on both series;Thir1 vessel walls were abnormal on both series,in which 3D ce-MRA showed stenosis or dilation while HRMRI showed the arterial wall thickened or loaded with plaques.In other 34 vessel walls,different findings between 3D ce-MRA and HRMRI were detected:26 abnormal vessel walls(5 with thickened wall and 21 with plaques)shown on HRMRI were normal on 3D ce-MRA,while 6 stenotic and 2 dilated vessel walls on 3D ce-MRA were relatively normal on HRMRI.Inter-observer reproducibility was good for identifying intra-and extracranial arterial wall abnormality on 3D ce-MRA and HRMRI(Kappa was 0.67,0.69,both P<0.001).Conclusion 3.0T HRMRI of simultaneous carotid and intracranial vessel wall can help to clearly visualize the anatomy and pathological changes of intra-and extracranial arterial wall,identify the stenosis missed on 3D ce-MRA,distinguish causes of arterial stenosis,and is valuable to diagnose intra-and extracranial arterial wall abnormality.%目的 探讨症状性大脑中动脉(MCA)狭窄患者颅内外动脉管壁病变特点和3.0T高分辨磁共振成像(High-resolution magnetic resonance imaging,HRMRI)头颈联合技术的临床应用价值.方法 11例症状性MCA狭窄患者接受三维增强磁共振血管成像(3D ce-MRA)与3.0T HRMRI的T1 w-db SPACE平扫和T1 w-db SPACE增强扫描,并结合头颈部颅内外动脉管壁不间断联合扫描新技术.结果 共扫描11例患者的88处颅内外动脉管壁,其结果发现:1例中枢神经系统血管炎,其左侧MCA及左侧颈内动脉(ICA)颅内段在T1 w-db SPACE像上表现为管壁环形增厚及环形强化;1例颅内动脉夹层,其左侧MCA在T1 w-db SPACE像呈长条状高信号,相应高信号在T2 w-db SPACE像上为等低信号;9例动脉粥样硬化患者均合并双侧MCA粥样硬化斑块,表现为管壁偏心性增厚,其中8例(88.9%)合并颅内外动脉粥样硬化,增强扫描见6例(67%)颅内外动脉粥样硬化斑块均有强化.比较3D ce-MRA与HRMRI结果发现,88处血管中,23处血管的3D ce-MRA与HRMRI均未见明显异常;31处血管的3D ce-MRA与HRMRI显示相对一致,即3D ce-MRA显示狭窄或者扩张、HRMRI显示管壁呈不同程度的增厚或附壁斑块;34处血管的3D ce-MRA与HRMRI显示欠一致,其中,26处血管的3D ce-MRA大致正常而HRMRI显示管壁增厚(5处)或斑块(21处),8处血管的3D ce-MRA显示轻度狭窄(6处)或扩张(2处)而HRMRI显示管腔外径及管壁均大致正常.判断颅内外动脉异常的组间一致性可(3D ce-MRA、HRMRI的 Kappa值分别为0.67、0.69,P<0.001).结论 3.0T HRMRI头颈联合技术可清晰地显示颅内外动脉的管壁结构和病变特点,识别3D ce-MRA未能发现的狭窄,甄别动脉狭窄的病因,对颅内外动脉管壁病变的诊断具有较高的临床应用价值.