Pericoronary adipose tissue (PCAT) is the deposition of fat in the vicinity of the coronary arteries. It is an indicator of coronary inflammation and associated with coronary artery disease. Non-invasive coronary CT angiography (CCTA) is presently used to obtain measures of the thickness, volume, and attenuation of fat deposition. However, prior works solely focus on measuring PCAT using semi-automated approaches at the right coronary artery (RCA) over the left coronary artery (LCA). In this pilot work, we developed a fully automated approach for the measurement of PCAT mean attenuation and volume in the region around both coronary arteries. First, we used a large subset of patients from the public ImageCAS dataset (n = 735) to train a 3D full resolution nnUNet to segment LCA and RCA. Then, we automatically measured PCAT in the surrounding arterial regions. We evaluated our method on a held-out test set of patients (n = 183) from the same dataset. A mean Dice score of 83% and PCAT attenuation of -73.81 $\pm$ 12.69 HU was calculated for the RCA, while a mean Dice score of 81% and PCAT attenuation of -77.51 $\pm$ 7.94 HU was computed for the LCA. To the best of our knowledge, we are the first to develop a fully automated method to measure PCAT attenuation and volume at both the RCA and LCA. Our work underscores how automated PCAT measurement holds promise as a biomarker for identification of inflammation and cardiac disease.

翻译：冠状动脉周围脂肪组织（PCAT）是冠状动脉附近的脂肪沉积物，它是冠状动脉炎症的标志物，并与冠状动脉疾病相关。目前，无创冠状动脉CT血管造影（CCTA）可用于获取脂肪沉积的厚度、体积及衰减值。然而，既往研究仅通过半自动方法测量右冠状动脉（RCA）周围的PCAT，而忽略了左冠状动脉（LCA）。本项初步研究开发了一种全自动方法，用于测量双冠状动脉周围区域的PCAT平均衰减值和体积。首先，我们利用公开的ImageCAS数据集中大量患者（n=735）训练了一个三维全分辨率的nnUNet模型，以分割LCA和RCA。随后，自动测量动脉周围区域的PCAT。我们在同一数据集的独立测试集（n=183）上评估了该方法。结果显示，RCA的平均Dice得分为83%，PCAT衰减值为-73.81±12.69 HU；LCA的平均Dice得分为81%，PCAT衰减值为-77.51±7.94 HU。据我们所知，这是首个实现RCA和LCA双动脉PCAT衰减值及体积全自动测量方法的研究。我们的工作表明，自动PCAT测量有望成为识别炎症和心脏疾病的生物标志物。