Department of Radiology and Cardiology, Erasmus Medical Center, Rotterdam, The Netherlands.
J Cardiovasc Med (Hagerstown). 2010 May;11(5):337-44. doi: 10.2459/JCM.0b013e3283312400.
The purpose of this study was to define the in-vitro and in-vivo effects of intracoronary enhancement on the absolute density values of coronary plaques during multislice computed tomography.
We studied seven ex-vivo left coronary artery specimens surrounded by olive oil and filled with isotonic saline and four solutions with decreasing dilutions of contrast material: control (isotonic saline), 1/200, 1/80, 1/50, and 1/20. The multislice computed tomography protocol was: slice/collimation 32 x 2 x 0.6 mm and rotation time 330 ms. The attenuation (Hounsfield units) value of atherosclerotic plaques was measured for each dilution in lumen, plaque (noncalcified coronary wall thickening), calcium, and surrounding oil. In-vivo assessment was performed in 12 patients (nine men; mean age 58.7 +/- 9.9 years) who underwent two subsequent multislice computed tomography scans (arterial and delayed) after intravenous administration of a single bolus of contrast material. The attenuation values of lumen and plaques during arterial and delayed computed tomography were compared. The results were compared with one-way analysis of variance and correlated with Pearson's test.
Mean lumen (45 +/- 38-669 +/- 151 HU) and plaque (11 +/- 35-101 +/- 72 HU) attenuation differed significantly (P < 0.001) among the different dilutions. The attenuation of lumen and plaque of coronary plaques showed moderate correlation (r = 0.54, P < 0.001). The mean attenuation value in vivo for the arterial and delayed phase scans differed significantly (P < 0.001) for lumen (325 +/- 70 and 174 +/- 46 HU, respectively) and plaque (138 +/- 71 and 100 +/- 52 HU, respectively).
Coronary plaque attenuation values are significantly modified by differences in lumen contrast densities both ex vivo and in vivo. This should be taken into account when considering the distinction between lipid and fibrous plaques.
本研究旨在确定冠状动脉内增强对多层螺旋 CT 冠状动脉斑块绝对密度值的体外和体内影响。
我们研究了七个用橄榄油包围并充满等渗盐水的左冠状动脉标本，以及四种浓度递减的对比剂溶液：对照（等渗盐水）、1/200、1/80、1/50 和 1/20。多层螺旋 CT 方案为：层厚/准直 32 x 2 x 0.6mm，旋转时间 330ms。对每种稀释液在管腔、斑块（非钙化冠状动脉壁增厚）、钙和周围油中的粥样斑块的衰减（亨氏单位）值进行了测量。体内评估在 12 名患者（9 名男性；平均年龄 58.7 +/- 9.9 岁）中进行，这些患者在静脉注射单次对比剂后进行了两次连续的多层螺旋 CT 扫描（动脉期和延迟期）。比较了动脉期和延迟期多层螺旋 CT 时管腔和斑块的衰减值。结果与单因素方差分析进行比较，并与 Pearson 检验相关。
不同稀释液之间管腔（45 +/- 38-669 +/- 151HU）和斑块（11 +/- 35-101 +/- 72HU）的衰减值差异有统计学意义（P < 0.001）。冠状动脉斑块的管腔和斑块的衰减值呈中度相关（r = 0.54，P < 0.001）。动脉期和延迟期扫描的体内平均衰减值在管腔（分别为 325 +/- 70 和 174 +/- 46HU）和斑块（分别为 138 +/- 71 和 100 +/- 52HU）方面差异有统计学意义（P < 0.001）。
管腔对比密度的差异显著改变了冠状动脉斑块的衰减值，无论是在体外还是体内。在考虑脂质和纤维斑块的区别时，应考虑到这一点。
