Estes J M, Quist W C, Lo Gerfo F W, Costello P
Department of Surgery, New England Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA.
J Cardiovasc Surg (Torino). 1998 Oct;39(5):527-34.
Evidence suggests that atherosclerotic plaque composition and morphology are more important predictors of plaque stability and clinical behavior than the degree of vessel stenosis. Unfortunately, noninvasive methods of plaque characterization in situ using duplex ultrasound have been largely unsuccessful. We investigated the accuracy of helical computed tomography (HCT) in defining plaque morphology in patients undergoing carotid endarterectomy.
Candidates for endarterectomy were enrolled prospectively and underwent HCT with intravenous contrast injection. The attenuation values (in Hounsfield Units) of plaque features such as calcium, fibrous tissue, and lipid were measured and correlated with the tissue types seen on microscopic examination. Percent luminal stenosis derived from transverse HCT images was also compared to values obtained from duplex ultrasound.
Ambulatory patients referred to a tertiary, metropolitan medical center.
A total of 21 out of 22 cases were suitable for comparison. Qualitatively, HCT accurately defined plaque features containing calcium, fibrous stroma, and lipid. Using tissue attenuation values (Hounsfield Units - H), HCT distinguished between lipid and fibrous stroma (means 39+/-12 H and 90+/-24 H, respectively, p<0.001). HCT-derived calculations of percent stenosis also correlated with the ultrasound data (p<0.001).
HCT is an accurate, noninvasive means for studying detailed plaque morphology and composition. This technique provides the basis for further studies correlating plaque anatomy with clinical behavior.
有证据表明，与血管狭窄程度相比，动脉粥样硬化斑块的成分和形态是斑块稳定性及临床行为更重要的预测指标。遗憾的是，利用双功超声对斑块进行原位无创特征分析的方法大多未获成功。我们研究了螺旋计算机断层扫描（HCT）在确定接受颈动脉内膜切除术患者的斑块形态方面的准确性。
前瞻性纳入内膜切除术候选患者，并在静脉注射造影剂后对其进行HCT检查。测量斑块特征（如钙、纤维组织和脂质）的衰减值（以亨氏单位计），并将其与显微镜检查所见的组织类型进行关联分析。还将横断位HCT图像得出的管腔狭窄百分比与双功超声获得的值进行比较。
转诊至一家大型都市三级医疗中心的门诊患者。
22例中有21例适合进行比较。定性分析显示，HCT能准确界定含有钙、纤维基质和脂质的斑块特征。利用组织衰减值（亨氏单位 - H），HCT能够区分脂质和纤维基质（均值分别为39±12 H和90±24 H，p<0.001）。HCT得出的狭窄百分比计算结果也与超声数据相关（p<0.001）。
HCT是研究斑块详细形态和成分的一种准确、无创的手段。该技术为进一步研究斑块解剖结构与临床行为之间的关系提供了基础。
