UNASSIGNED: A total of 330 patients with suspicious coronary atherosclerosis were enrolled and underwent coronary CT angiography with dual-layer spectral detector CT (SDCT). Proximal and peri-plaque fat attenuation index (FAI) of stenosis coronary arteries were measured using both conventional images (CIs) and virtual monoenergetic images (VMIs) ranging from 40 keV to 100 keV. The slopes of the spectral attenuation curve (λ) of proximal and peri-plaque PCAT at three different monoenergetic intervals were calculated. Additionally, peri-plaque FAI on CI and virtual non-contrast images, and effective atomic number were measured manually.
UNASSIGNED: A total of 231 coronary arteries with plaques and lumen stenosis were finally enrolled. Peri-plaque FAICI and FAIVMI were significantly higher in severe stenosis than in mild and moderate stenosis (p < 0.05), while peri-plaque λ, proximal FAI, and proximal λ were not statistically different. Proximal FAI, peri-plaque FAI, and peri-plaque λ were significantly higher in low-density non-calcified plaque (LD-NCP) and non-calcified plaque (NCP) than in calcified plaque (p < 0.01). Peri-plaque FAI was the highest in the LD-NCP group, while proximal FAI was the highest in the NCP group. In severe stenosis and in LD-NCP, peri-plaque FAI was significantly higher than proximal FAI (p < 0.05). The manually measured parameters related to peri-plaque PCAT attenuation had a positive correlation with the results of peri-plaque FAI measured automatically.
UNASSIGNED: Peri-plaque PCAT has more value in assessing coronary atherosclerosis than proximal PCAT. Peri-plaque PCAT attenuation is expected to be used as a standard biomarker for evaluating plaque vulnerability and hemodynamic characteristics.
■共纳入330例可疑冠状动脉粥样硬化患者,并使用双层能谱探测器CT(SDCT)进行冠状动脉CT血管造影。使用常规图像(CI)和虚拟单能量图像(VMI)测量狭窄冠状动脉的近端和斑块周围脂肪衰减指数(FAI),范围为40keV至100keV。计算了在三个不同的单能量间隔下近端和斑块周围PCAT的光谱衰减曲线(λ)的斜率。此外,斑块周围FAIonCI和虚拟非造影图像,并手动测量有效原子序数。
■最终纳入了231条有斑块和管腔狭窄的冠状动脉。重度狭窄患者斑块周围FAICI和FAIVMI明显高于轻度和中度狭窄患者(p<0.05),而斑块周围的λ,近端FAI,和近端λ没有统计学差异。近端FAI,周边FAI,低密度非钙化斑块(LD-NCP)和非钙化斑块(NCP)的斑块周围λ明显高于钙化斑块(p<0.01)。LD-NCP组斑块周围FAI最高,而NCP组的近端FAI最高。在重度狭窄和LD-NCP中,斑块周围FAI显著高于近端FAI(p<0.05)。与斑块周围PCAT衰减相关的手动测量参数与自动测量的斑块周围FAI结果呈正相关。
■斑块周围的PCAT在评估冠状动脉粥样硬化方面比近端PCAT更有价值。斑块周围PCAT衰减有望用作评估斑块易损性和血液动力学特征的标准生物标志物。