高分辨磁共振成像与超声检查对颈动脉粥样硬化评价的对比研究

目的比较高分辨MRI与超声检查对颈动脉粥样硬化的评价。方法选择经超声诊断为颈动脉狭窄≥50%的患者100例,进行主动脉弓上血管对比增强磁共振血管造影(CEMRA),对狭窄侧颈动脉做高分辨颈动脉斑块MRI,判断颈动脉斑块类型。比较MRI对血管腔狭窄及斑块形态诊断与超声的差异。结果与数字减影血管造影比较,CEMRA判断血管狭窄程度的准确性为100%,明显高于超声的准确性74%。超声显示,硬斑和均匀低回声的脂质型斑块相当于MRI的AHA标准Ⅲ和Ⅶ期,较大低回声和不均质混合型斑块相当于Ⅳ～V期和Ⅵ期。结论 MRI对斑块分期更准确,可充分显示硬化斑块的形态结构,判断血管管腔狭窄程度有较高的准确性。

The comparative study of high-resolution MRI and ultrasound in assessment of carotid atherosclerosis

Objective To compare the high-resolution MRI and ultrasound in evaluating carotid atherosclerosis.Methods 100 patients with carotid artery stenosis ≥50% were diagnosed by ultrasound. Contrast enhanced magnetic resonance angiography (CEMRA) of vessel above aortic arch was performed.The right carotid artery stenosis was selected to do high-resolution carotid artery plaque MRI for further determining the type of carotid artery plaque.The differences of vascular stenosis and plaque morphology detected by MRI and ultrasound were compared.Results Compared with the digital subtraction angiography,CEMRA had an accuracy of 100% in determining the degree of stenosis,while ultrasound showed an accuracy of 74%.The plaque of hard and low-echo type on ultrasound was equivalent to AHA standards Ⅲ and Ⅶ on MRI,while large low echo and non-homogeneous mixed plaque was equivalent to Ⅳ-Ⅴ and Ⅵ stage.Conclusion MRI is more accurate for staging the plaque and can fully demonstrate the morphology of plaques and determine the narrowness of lumen with high degree of accuracy.