Assessment of Epicardial Fat Volume With Threshold-Based 3-Dimensional Segmentation in CT: Comparison With the 2-Dimensional Short Axis-Based Method

Background and Objectives: We aimed to assess the usefulness of a threshold-based, 3-dimensional (3D) segmentation in comparison with the traditional 2-dimensional (2D) short axis-based method for measurement of epicardial fat volume with 64-slice multidetector computed tomography (MDCT). Subjects and Methods: One hundred patients (52 males; mean age, 58.36${\pm}$11.0 years) who underwent coronary CT angiography were enrolled in this study. The epicardial fat volume was measured using the two methods. The existing method was the 2D short axis-based method and the new method was the threshold-based 3D segmentation. Pearson's correlation was used to compare the two measurement methods. We also assessed the relationship between the epicardial fat volume and coronary artery disease (CAD). Results: There were a strong correlation between the epicardial fat volumes determined using the two methods (r=0.956, p<0.001). The mean overestimation of epicardial fat volume by the threshold-based 3D method was 59.89${\pm}$12.00% compared to the 2D short-axis based method. Using the 3D method, the epicardial fat volume was significantly higher in the CAD group than in the controls (165.07${\pm}$48.22 $m^3$ vs. 108.39${\pm}$48.03 $m^3$, p<0.001). Conclusion: Threshold-based 3D segmentation is another easy and useful tool for measuring the epicardial fat volume.