单倍剂量对比剂结合快速成像技术在下肢动脉3D CE-MRA中的应用简

目的探讨使用单倍剂量对比剂结合快速成像技术行下肢动脉三维动态磁共振增强血管成像（3DDCE-MRA）的检查方法及临床应用。资料与方法56例临床怀疑下肢血管病变的患者，以2m1／s速度，一次注射单倍剂量（0．1mmol／kg）对比剂，行下肢动脉3DDCE-MRA检查。采用小剂量团注试验法（Test-bolus）测试延迟时间，应用小角度快速激发梯度回波序列（3D-FLASH）结合各种决速成像技术，获得各段靶血管最大密度投影图像（MIP）并进一步后处理重建。图像质量分为3个等级，同时观察下肢动脉的病变情况。结暴所有患者均能完成检查，56例下肢动脉血管显示清晰，静脉污染轻，达到Ⅰ或Ⅱ级标准，无Ⅲ级图像。5例结果未见异常，51例发现血管病变。结论采用1．5T磁共振仪结合各种快速成像技术，使用单倍剂量（0．1mmol／kg）对比剂一次性注射，行下肢动脉3DDCE-MRA成像，可以满足临床诊断需求。

Application of Single-dose Contrast Agent Combined with Fast Imaging on Lower Extremity Artery 3D CE-MRA

Objective To explore the method and its clinical application of single-dose contrast agent combined with fast imaging on lower extremity arteries 3D DCE-MRA. Materials and Methods 56 cases with suspected lower extremity arterial disease were injected with single dose contrast agent（0.1mmol/kg, 2ml/s） , and then underwent lower extremity arterial 3D DCE-MRA. Low dose testing method were adopted to test delay times. Small-angle stirred 3D-FLASH combined with various fast imaging techniques were used to get maximum intensity projection （MIP） of target vessels, and further reconstruction were performed. Image quality was classified into 3 levels, and lesions of lower extremity arteries were evaluated. Results All the patients finished the examination, and lower extremity arteries of 56 cases could show clearly with slight pollution of vein. The quality of all images could reach class Ⅰ or Ⅱ, and with no image of class Ⅲ. 5 cases showed no obvious abnormality, and 51 cases showed vascular lesions. Conclusion 1.5T MR. scanner combined with various fast imaging techniques and single-dose contrast agent one-time injection on lower extremity arteries 3D DCE-MR.A can meet the demand for clinical diagnosis.