Inokuchi Go, Kojima Masatoshi, Chiba Fumiko, Hoshioka Yumi, Yoshida Maiko, Tsuneya Shigeki, Iwase Hirotaro
Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan.
Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo- ku, Tokyo, 113-0033, Japan.
Int J Legal Med. 2025 Jan;139(1):119-130. doi: 10.1007/s00414-024-03321-0. Epub 2024 Sep 12.
Although coronary computed tomography (CT) angiography is a useful tool for evaluating coronary artery lesions both ante- and postmortem, accurate evaluation of the lumen is difficult when highly calcified lesions are present, owing to overestimation of stenosis caused by blooming and partial volume artifacts. In clinical practice, to overcome this diagnostic problem, a subtraction method has been devised to remove calcification by subtracting the precontrast image from the contrast image. In this report, we describe a calcification subtraction method using image analysis software for postmortem coronary CT angiography. This method was devised based on preliminary experimental results showing that the most accurate subtraction was achieved using images reconstructed with a narrower field of view and bone kernel, resulting in higher spatial resolution. This subtraction method allowed evaluation of lumen patency and the degree of stenosis on contrast-enhanced images in a verification using actual specimens where evaluation of the lumen had been difficult because of high calcification. The results were morphologically similar to the macroscopic findings. This method allows more rapid and reliable lesion retrieval and is expected to be useful for postmortem coronary angiography in forensic practice.
尽管冠状动脉计算机断层扫描（CT）血管造影术是评估生前和死后冠状动脉病变的有用工具，但当存在高度钙化病变时，由于 blooming 和部分容积伪影导致的狭窄高估，对管腔进行准确评估较为困难。在临床实践中，为克服这一诊断问题，已设计出一种减法方法，通过从对比图像中减去对比前图像来去除钙化。在本报告中，我们描述了一种使用图像分析软件进行死后冠状动脉CT血管造影钙化减法的方法。该方法是基于初步实验结果设计的，结果表明使用更窄视野和骨内核重建的图像可实现最准确的减法，从而获得更高的空间分辨率。这种减法方法能够在使用实际标本进行的验证中，评估对比增强图像上的管腔通畅性和狭窄程度，在实际标本中，由于高度钙化，管腔评估一直很困难。结果在形态上与宏观发现相似。该方法能够更快速、可靠地检索病变，有望在法医实践中的死后冠状动脉造影中发挥作用。
