Bucher Andreas M, Joseph Schoepf U, Krazinski Aleksander W, Silverman Justin, Spearman James V, De Cecco Carlo N, Meinel Felix G, Vogl Thomas J, Geyer Lucas L
Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA; Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Frankfurt, Germany.
Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA; Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA.
Eur J Radiol. 2015 Jun;84(6):1062-7. doi: 10.1016/j.ejrad.2015.03.018. Epub 2015 Mar 25.
To systematically analyze the influence of technical parameters on quantification of epicardial fat volume (EATV) at cardiac CT.
153 routine cardiac CT data sets were analyzed using three-dimensional pericardial border delineation. Three image series were reconstructed per patient: (a) CTAD: coronary CT angiography (CTA), diastolic phase; (b) CTAS: coronary CTA, systolic phase; (c) CaScD: non-contrast CT, diastolic phase. EATV was calculated using three different upper thresholds (-15HU, -30 HU, -45HU). Repeated measures ANOVA, Spearman's rho, and Bland Altman plots were used.
Mean EATV differed between all three image series at a -30HU threshold (CTAD 87.2 ± 38.5 ml, CTAS 90.9 ± 37.7 ml, CaScD 130.7 ± 49.5 ml, P<0.001). EATV of diastolic and systolic CTA reconstructions did not differ significantly (P=0.225). Mean EATV for contrast enhanced CTA at a -15HU threshold (CTAD15 102.4 ± 43.6 ml, CTAS15 105.3 ± 42.3 ml) could be approximated most closely by non-contrast CT at -45HU threshold (CaScD45 105.3 ± 40.8 ml). The correlation was excellent: CTAS15-CTAD15, rho=0.943; CTAD15-CaScD45, rho=0.905; CTAS15-CaScD45, rho=0.924; each P<0.001). Bias values from Bland Altman Analysis were: CTAS15-CTAD15, 4.9%; CTAD15-CaScD45, -4.3%; CTAS15-CaScD45, 0.6%.
Measured EATV can differ substantially between contrast enhanced and non-contrast CT studies, which can be reconciled by threshold modification. Heart cycle phase does not significantly influence EATV measurements.
系统分析心脏CT技术参数对心外膜脂肪体积（EATV）定量的影响。
采用三维心包边界描绘法分析153例常规心脏CT数据集。每位患者重建三个图像系列：（a）CTAD：冠状动脉CT血管造影（CTA），舒张期；（b）CTAS：冠状动脉CTA，收缩期；（c）CaScD：非增强CT，舒张期。使用三种不同的上限阈值（-15HU、-30HU、-45HU）计算EATV。采用重复测量方差分析、Spearman秩相关分析和Bland Altman图分析。
在-30HU阈值下，所有三个图像系列的平均EATV存在差异（CTAD 87.2±38.5ml，CTAS 90.9±37.7ml，CaScD 130.7±49.5ml，P<0.001）。舒张期和收缩期CTA重建的EATV差异无统计学意义（P=0.225）。在-15HU阈值下，对比增强CTA的平均EATV（CTAD15 102.4±43.6ml，CTAS15 105.3±42.3ml）与-45HU阈值下的非增强CT（CaScD45 105.3±40.8ml）最接近。相关性极佳：CTAS15-CTAD15，rho=0.943；CTAD15-CaScD45，rho=0.905；CTAS15-CaScD45，rho=0.924；各P<0.001）。Bland Altman分析的偏差值为：CTAS15-CTAD15，4.9%；CTAD15-CaScD45，-4.3%；CTAS15-CaScD45，0.6%。
对比增强CT和非增强CT研究中测量的EATV可能存在显著差异，可通过阈值调整来协调。心动周期阶段对EATV测量无显著影响。
