320排CT在冠状动脉钙化斑块与非钙化斑块狭窄对比研究中的应用

Calcified and Non-calcified Coronary Atherosclerotic Plaques and Stenosis Researched with 320-slices CT

目的按钙化斑块与非钙化斑块进行分类,对照冠状动脉造影(CAG),研究320排CT对冠状动脉粥样硬化斑块狭窄程度判断的准确性、影响因素及解决方法。方法 102名患者行320排CT冠状动脉血管成像(CTA)检查共发现396个冠状动脉斑块,同期行CAG检查,对斑块造成管腔狭窄程度按无、轻、中、重、闭塞5个级别计算两种方法的符合率。按钙化、非钙化斑块分类计算符合率。钙化斑块按钙化阈值>150 HU、>250 HU、>350 HU、>600 HU共4个方案进行计算。结果 CTA显示钙化斑块占68.2%,非钙化斑块占31.8%。6%的斑块为不稳定斑块。7.8%的斑块不导致狭窄。钙化阈值设定>150 HU、>250 HU、>350 HU的符合率测量无明显差异,但>600 HU时有减低。CTA显示冠状动脉斑块性狭窄与CAG符合率为88.4%(非钙化斑块94.4%,钙化斑块85.6%,二者差异显著)。不相符多表现于对钙化斑块狭窄程度的高估。结论与CAG对照,冠状动脉CTA显示斑块狭窄符合率较高(88.4%),其中非钙化斑块狭窄符合率(94.4%)明显高于钙化斑块(85.6%);少数病例存在对钙化斑块狭窄程度的高估。因此CTA在非钙化斑块诊断上具有明显优势,钙化阈值设为>350 HU较合适。

Aim To research the affect factors and the solutions for diagnosis of coronary stenosis with arterio- sclerosis plaques that were divided into two categories （the non-calcified plaques and calcified plaques） with 320-slices computed tomography angiography （CTA） compared with tocoronary angiography （CAG）. Methods 396 coronary arteriosclerosis plaque lesions were found in 102 patients examed by CTA and CAG. They were divided into five groups according to vascular stenosis degree ： normal, mild, moderate, severe and occlusion. The coincidence rate of vascular stenosis degree by CTA were calculated compared with CAG with lesions divided into two categories （the non-calcified plaques and calcified plaques）. The calcium threshold for calcified plaques is set in four different programmes： 〉 150 HU, 〉 250 HU, 〉350 HU, 〉600 HU. Results CTA shows the 396 arteriosclerosis plaques with 68.2% for calcified plaques and 31.8% for non-calcified plaques, and 6% is unstable plaques, 7.8% without vascular stenosis. It is the same as calcium threshold in groups of 〉 150 HU, 〉250 HU, 〉350 HU for the coincidence rate of vascular stenosis degree comparing CTA with CAG but lower in group of 〉 600 HU. The coincidence rate comparing CTA with CAG of is 88.4% （94.4% for non-calcified plaques and 85.6% for calcified piaques）. Stenosis degree is often overestimated in calcified plaques. Conclusions The coincidence rate of vascular stenosis degree comparing CTA with CAG is high （88.4%）. The coincidence rate of non-calcified plaques （94. 4% ） is higher than calcified plaques （85.6%）. The coronary stenosis degree is overestimated in calcified plaques. CTA has the advantage for non-calcified plaque valuation. It is reasonable for calcium threshold starting with 350 HU.