64层双源螺旋CT与血管内超声对冠状动脉粥样硬化斑块性质的对比研究

目的对比冠状动脉血管内超声(IVUS)与64层双源螺旋CT(64-sCT)检查对冠状动脉粥样硬化斑块特征判定的准确性。方法选择35例不稳定性心绞痛患者行64-sCT与IVUS检查,分别测定同一病变同一位置的血管横截面积、管腔横截面积、斑块负荷;采用IVUS判定斑块性质,64-sCT测定其CT值。结果 45支血管(左前降支23支;左回旋支15支;右冠状动脉7支)的72个不同截面行IVUS与64-sCT检查,在可用于评估的68个截面中,64-sCT对51个存在斑块的截面,正确显示49个存在斑块(敏感性96%),对提示17个无斑块的截面,正确显示16个无斑块存在(特异性94%)。脂质斑块(25±14)HU、纤维斑块(90±20)HU、钙化斑块(530±185)HU;混合斑块中,钙化-脂质斑块(540±175)HU、钙化-纤维斑块(540±195)HU、纤维-脂质斑块(91±22)HU。纤维-脂质斑块与纤维斑块差异无统计学意义;钙化-脂质斑块、钙化-纤维斑块与钙化斑块差异无统计学意义。靶血管外弹力膜截面积、管腔截面积、斑块负荷、狭窄程度之间差异无统计学意义。结论对比IVUS与64-sCT检查能够定性及定量分析冠状动脉粥样硬化斑块,但其精确度仍有一定的限制。

Coronary plaque characterization by 64-slice dual-source spiral computed tomography and IVUS

Objective To compare the accuracy of 64-slice dual-source spiral computed tomography (64-sCT) and intravascular ultrasound(IVUS) in characterizing the coronary plaque. Methods 64-sCT and IVUS (motorized pullback) were performed in thirty-five patients with unstable angina pectoris. Vascular cross-sectional area (CSA), luminal CSA and plaque burden were measured in same lesion at same position. Plaque component was also evaluated by IVUS and Hounsfield unit(HU) was calculated according to 64-sCT. Results A total of 72 segments in 45 vessels (left anterior descending 23, left circumflex 15, and right coronary artery 7) were investigated by both IVUS and 64-slice CT. Among 68 assessable segments, 64-sCT correctly detected 49 of the 51 segments with plaques (sensitivity: 96%), and correctly evaluated 16 of 17 segments without plaques (specificity: 94%). Plaque analysis software was used to predetermine the Hounsfield unit ranges for different components of plaque. 64-sCT was able to differentiate fibrous(90±20) HU,soft(25±14) HU and calcified plaques(530±185)HU. However, Hounsfield unit was less reliable in differentiating between fibrous and fibrous-soft plaque, and between calcification and cal-fibrous plaque and cal-soft plaque. External elastic membrane cross section area,luminal cross section area, plaque burden and vessel stenosis were not significantly different between CT and IVUS. Conclusion Compared with IVUS, 64-sCT is reliable in identifying and quantifying coronary atherosclerotic plaques. However, plaque characterization is less accurate.