ABSTRACT
Objective To investigate the diagnostic value of sharp kernel reconstructed images for calcified plaque coronary artery stenosis with a dual-source CT.Methods 42 patients with suspected coronary disease underwent dual-source coronary computed tomography angiography (CCTA) and coronary angiography (CAG).The CCTA images were respectively reconstructed by smooth kernel (I26f) and sharp kernel (I46f) reconstruction.The image noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured,and then the calcified plaque noise of two groups reconstructed image was scored subjectively.A total of 56 vascular stenoses that caused by calcification were taken as the research object,according to the results of CAG as a golden standard.The ROC curves of two groups were drawn with moderate stenosis (more than or equal to 50%) and severe stenosis (more than or equal to 75%), and the corresponding sensitivity, specificity, and optimal threshold were obtained.Results The images of I46f group had higher noise [I46f:(45.43±9.00) HU;I26f:(31.43±5.55) HU;t=-8.58,P=0.000],lower SNR [I46f:(10.26±2.09) HU;I26f:(14.86±3.53) HU;t=7.28,P=0.000] and lower CNR[I46f:(14.04±4.51) HU;I26f:(20.80±7.18) HU;t=5.17,P=0.000],but the subjective scoring of calcified plaque of I46f group was better than that of I26f group(I46f:2.33±0.75;I26f:1.64±0.70,Z=-4.61,P=0.000).The ROC curves of two groups: with moderate stenosis(≥50%),area under the I46f curve(0.946) was larger than that of I26f group (0.935);to diagnose with the reconstructed image of group I46f,the optimal threshold was 55%,the specificity was 95.0%,and sensitivity was 88.9%;and for I26f group,the optimal threshold was 65%, the specificity was 90%, and sensitivity was 88.9%.With severe stenosis(≥75%), area under the I46f curve (0.927) was slightly larger than that of I26f group (0.924);to diagnose with the reconstructed image of group I46f,the optimal threshold was 77.5%,the specificity was 79.1%,and sensitivity was 92.3%;for I26f group, the optimal threshold was 85%, the specificity was 74.4%,and the sensitivity was 100%.Conclusion The I46f reconstruction image of dual-source CT has more advantageous than the I26f reconstruction image,and it is a better way to diagnosethe calcified coronary stenosis.