三维增强磁共振血管成像诊断下肢动脉狭窄闭塞性疾病

Arterial stenosal and occlusive diseases of lower limb:Applicable study of three dimension contrast-enhanced magnetic resonance angiography

目的探讨三维增强磁共振血管成像技术(3DCE-MRA)诊断和评价下肢动脉狭窄闭塞性疾病的临床应用价值。方法对临床疑诊患有下肢动脉狭窄闭塞性疾病的38例患者,进行3DCE-MRA检查。选择FLASH3D冠状位压脂序列。快速注射大剂量顺磁性对比剂后,根据计算出的延迟扫描时间,采集下肢相应部位的增强图像。增强图像与其相应阶段非增强图像经减影处理和最大强度投影法处理后,得到下肢动脉血管三维图像。对28例经数字减影血管造影(DSA)证实的下肢动脉血管造影图像与3DCE-MRA图像进行比较。结果图像经减影及最大强度摄影(MIP)后处理均得到清晰的下肢动脉三维MRI,发现下肢动脉狭窄闭塞性疾病32例,共检测出在11个血管阶段中发现狭窄病变237处。在同时具有DSA与3DCE-MRA图像资料的28例中,3DCE-MRA发现狭窄病变201处,DSA检查发现狭窄病变218处,两项检查诊断结果经统计学处理,无显著性差异(P>0.05)。结论3DCE-MRA技术在观察和测量下肢动脉血管分级、狭窄部位、程度等方面,具有与下肢动脉DSA相同的检查效果。

Objective To evaluate the clinical application value of a three-dimension contrast enhanced MR angiographic technique for diagnosis and assessment of the arterials stenosis disease of lower limb.Methods Thirty-eight patients with suspected stenosed and occlusive disease of arterials underwent three-dimension contrast enhanced MR angiography (3D CE-MRA). 3D FLASH with fatty-suppressed sequences in coronary position were planned to cover the lower limb to acquire the pre-enhanced imaging. After fast injection of Gd-DTPA, acquisition was applied with the delayed time to acquire the enhanced imaging. Further post-processing including subtraction and MIP reconstruction were performed with the pre- and post- enhancement imaging of the same anatomic position in order to acquire the 3D MRA.Results Distinct imaging of 3D CE-MRA could be obtained on a workstation through subtraction and MIP post-processing on the basis of source in the 38 patients who underwent 3D CE-MRA examination. The arterials stenosis disease of lower limb were found in 32 cases. The 237 stenosis were found in 11 of arterials segments; 28 cases underwent 3D CE-MRA and DSA were compared; 201 stenosis were found in 3D CE-MRA and 218 stenosis were found in DSA (P>0.05).Conclusion In comparing with intra-arterial DSA, 3D CE-MRA has the same effect in demonstrating and detecting the position and degree of arterial stenosis of lower limb, and in grading the blood vessels.