三维动态对比增强磁共振血管造影技术在胸腹部大血管疾病诊断中的影像学特征分析

Analysis on the imaging characteristics of 3D dynamic contrast-enhanced MRA technique in the diagnosis of thoracic and abdominal macro vascular diseases

目的:探讨三维对比增强磁共振血管造影(3DCE-MRA)技术在胸腹部大血管疾病诊断中的影像学特征及应用价值。方法:选取28例患有胸腹部主动脉病变的患者,所有患者均行3DCE-MRA检查,行平扫轴位常规T_(1)加权成像(T_(1)WI)和T_(2)加权成像(T_(2)WI);再采用小剂量对比剂行轴位单层动态扫描,获得扫描延迟时间,平扫后采集靶血管冠状位图像作为后期减影的蒙片。利用获得的延迟时间行3DCE-MRA血管造影技术。注射对比剂后采集2次靶血管冠状位图像与增强前蒙片减影,分别为动脉期和静脉期。采集增强后的轴位快速自旋回波(FSE)序列T_(1)WI,观察胸腹部主动脉血管病变的信号表现。结果:28例患者中,大动脉炎5例(占17.9%),髂动脉瘤1例(占3.6%),动脉粥样硬化3例(占10.7%),肾动脉狭窄6例(占21.4%),主动脉瘤13例(占46.4%),3DCE-MRA血管造影技术对28例患者胸腹部主动脉血管及分支血管的病变显示效果良好。结论:3DCE-MRA技术诊断明确,且具有准确、快速及无创伤的优点。

Objective:To investigate the application value of three-dimensional contrast-enhanced magnetic resonance angiography(3DCE-MRA)in thoracic and abdominal macro vascular diseases.Methods:A total of twenty-eight patients with thoracic and abdominal aortic disease were selected to undergo 3DCE-MRA examination with conventional T_(1)-weighted image(T_(1)WI)and T_(2)-weighted image(T_(2)WI)of plain scanning axis position.Low-dose contrast agent was adopted to undergo single layer dynamic scanning of axial position so as to obtain the delay time of scan.And then,the plain scan collected coronary images of target blood vessels as the mask of post subtraction.The obtained delay time in the last step was used to undergo 3DCE-MRA.After contrast agent was injected,the coronary images of target blood vessels and the subtraction of mask pre enhancement were respectively collected at arterial and venous phases.At the last,the axial fast spin echo(FSE)T_(1)WI post enhancement was collected,and the signal performances of vascular lesions of thoracic and abdominal aorta were observed.Results:In the 28 patients,5 cases were aorto-arteritis(17.90%),and 1 case was lilac artery aneurysm(3.6%),and 3 cases were atherosclerosis(10.7%),and 6 cases were renal artery stenosis(21.4%)and 13 cases were aortic aneurysm(46.4%).The display effect of 3DCEMRA technique was favorable for the aortic vessels and branches of chest and abdomen of 28 patients.Conclusion:The diagnosis of 3DCE-MRA technique is definite,which has the advantages of accurate,rapid and non-invasive diagnosis.