Accuracy of evaluate coronary soft plaque by multi-slice CT / 中华放射学杂志

ABSTRACT

Objective To evaluate accuracy of density measurements within coronary plaque by multi-slice spiral CT and factors that influence measurements. Methods Four adult cadaver hearts were used. Thrombus and pericardial fat which acquired from specimen (size 2.0, 1.5, 1.0 and 0.5 mm respectively) were placed into coronary artery to simulate coronary plaques. The contrast medium (three different concentrations 1: 30, 1:40, and 1:50) were injected into coronary artery. The raw date were reconstructed with two slice width ( 1. 00 and 0. 75 mm). Results When contrast medium concentrations was 1: 30, the CT values of thrombus were 109 HU ( slice width 1. 00 mm, size 2. 0 mm) , 115 HU ( slice width 1.00 mm, size 1.5 mm), 101 HU (slice width 0.75 mm, size 2.0 mm), 113 HU ( slice width 0. 75 mm,size 1. 5 mm) ; the CT values of fat were - 23 HU ( slice width 1. 00 mm, size 2. 0 mm) , -17 HU(slice width 1.00 mm, size 1.5 mm) , -9 HU(slice width 1.00 mm, size 1.0 nun), -27 HU ( slice width 0.75 mm, size 2. 0 mm) , - 19 HU (slice width 0.75 mm, size 1. 5 mm) , - 13 HU (slice width 0. 75 mm,size 1. 0 mm). When contrast medium concentrations was 1: 40, the CT values of thrombus were 79 HU( slice width 1.00 mm,size 2.0 mm) , 87 HU( slice width 1.00 mm, size 1. 5 mm) , 115 HU( slice width 1. 00 mm,size 1. 0 mm) , 73 HU(slice width 0. 75 mm,size 2. 0 mm) , 80 HU(slice width 0. 75 mm, size 1. 5 mm) , 110 HU( slice width 0. 75 mm, size 1. 0 mm) ; the CT values of fat were - 31 HU ( slice width 1. 00 mm, size 2. 0 mm) , - 22 HU ( slice width 1. 00 mm, size 1. 5 mm) , - 10 HU ( slice width 1.00 mm,size 1.0 mm) , -35 HU(slice width 0. 75 mm,size 2.0 mm) , -25 HU(slice width 0. 75 mm, size 1. 5 mm) , - 19 HU ( slice width 0. 75 mm, size 1. 0 mm). When contrast medium concentrations was 1:50, the CT values of thrombus were 53 HU ( slice width 1. 00 mm, size 2. 0 mm) , 60 HU ( slice width 1.00 mm,size 1.5 mm) ,63 HU(slice width 1.00 mm,size 1.0 mm) ,51 HU(slice width 0.75 mm,size 2. 0 mm) ,64 HU( slice width 0. 75 mm,size 1. 5 mm) ,67 HU( slice width 0. 75 mm,size 1. 0 mm) ,145 HU (slice width 0. 75 mm, size 0. 5 mm) ; the CT values of fat were - 39 HU ( slice width 1. 00 mm, size 2. 0 mm) , -28 HU( slice width 1. 00 mm,size 1. 5 mm) , - 22 HU( slice width 1. 00 mm,size 1. 0 mm) , 17 HU(slice width 1. 00 mm,size 0. 5 mm) , -41 HU(slice width 0. 75 mm,size 2. 0 mm), -36 HU(slice width 0. 75 mm, size 1. 5 mm ) , - 27 HU ( slice width 0. 75 mm, size 1. 0 mm ) , 3 HU ( slice width 0. 75 mm, size 0. 5 mm ) . The density values of thrombus were correlated with size ( t = - 6. 624, P 0. 05) not found statistically significant may be caused by both too close slice width (1.0 mm and 0. 75 mm) and few samples. The slice width(t= -2. 595,P