腹部大血管病变的3D DCE-MRA诊断

目的 阐述3D动态增强磁共振血管造影（three-dimensional　dynamic contrast-enhanced magnetic resonance angiog-raphy,3D DCE-MRA）的原理及其在腹部大血管病变诊断中的价值。方法搜集32例腹部大血管3D DCE-MRA检查的影像资料,对其影像表现进行回顾性分析。结果（1）团注试验:对比剂通过肾动脉水平腹主动脉内的高峰时间为17-23s;（2）正常表现3例,清晰显示腹主动脉及其分支;（3）腹主动脉瘤7例,均显示主动脉受累段不规则增宽及实际的动脉腔;（4）腹主动脉夹层18例,均显示内膜片、真假两腔以及分支动脉起源的位置,显示破口12处、再破口16处;（5）动脉粥样硬化3例,均显示腹主动脉迂曲,管径粗细不均;（6）髂总静脉血栓形成1例,左髂总静脉未显影。结论3DDCE-MRA是一种非损伤性血管成像技术,对腹部大血管病变的诊断有重要意义。

Diagnosis of lesions in the major abdominal blood vessels by three-dimensional dynamic contrast-enhanced magnetic resonance angiography

Objective To elucidate the working principles of three-dimensional dynamic contrast-enhanced magnetic resonance angiography (3D DCE-MRA)and assess its value in the diagnosis of lesions in the major abdominal blood vessels. Methods The imaging data of 3D DCE-MRA and conventional MR examination in 32 cases of suspected major abdominal blood vessel diseases were obtained and analyzed retrospectively. Results The peak flow of contrast agents through the abdominal aorta at the level of renal artery occurred 17 to 23 s after the injections. Normal presentation was found in 3 cases, with clear images of the abdominal aorta and its branches. Abdominal aortic aneurysm was identified in 7 cases, where the involved segment of the aorta was irregularly broadened and the actual lumen of the abdominal aorta was displayed. Aortic dissection was found in 18 cases, and the intima, the double-lumen, and the position where the abdominal aortic branches originated could be seen with 12 entry sites and 16 re-entry sites. Atherosclerosis was found in 3 cases, with tortuous abdominal aorta whose lumen was morphologically irregular. One case was found with thrombosis in the left iliac vein which was not visualized. Conclusions 3D DCE-MRA is a non-invasive alternative for conventional angiography and has significant importance in the diagnosis of lesions in major abdominal blood vessels.