Clinic for Radiology and Nuclear Medicine, Cantonal Hospital Saint-Gallen, 9007 Saint-Gallen, Switzerland.
Institute of Forensic Medicine, Virtopsy, University of Zurich, 8057 Zurich, Switzerland.
Diagn Interv Imaging. 2020 Jul-Aug;101(7-8):489-497. doi: 10.1016/j.diii.2020.01.009. Epub 2020 Jan 29.
The purpose of this study was to compare an established postmortem contrast medium mixture based on polyethylene glycol (PEG) to an isotonic crystalloid with acetated Ringer solution (AR) as the base, both mixed with water-soluble iodinated contrast medium for postmortem computed tomography angiography (PMCTA) with the aim to avoid alterations of the corpse during autopsy.
The study included 20 cadavers; 10 had PMCTA with AR and 10 with PEG. PMCTA images were analyzed with respect to image quality, vascular contrast patterns and artifacts. Autopsy was evaluated for visual, organ, vessel and haptic alterations. The Wilcoxon rank sum test was used to search for differences in image quality between the two groups. Statistical significance was set at P<0.05.
AR provided excellent contrast within the right coronary artery (P<0.001) but a lack of contrast within the left coronary artery (P=0.008) whereas PEG showed the opposite. A better image quality was observed in the PEG group by comparison with the AR group for right common carotid artery (P=0.03), left common carotid artery (P=0.01) and left coronary artery (P=0.008). No differences were found for ascending aorta (P=0.65), aortic arch (P=0.09), right circle of Willis (P=0.17), left circle of Willis (P=0.08), inferior vena cava (P=0.07) and abdominal aorta (P=0.08). Severe extravasation occurred in all (10/10; 100%) cadavers in the AR group but in none (0/10; 0%) in the PEG group (P<0.001). At autopsy, visual alteration with lilac discoloration of the face was observed in 4/10 cadavers (40%) in the AR group and in 9/10 cadavers (90%) in the PEG group (P=0.057). Haptic alterations were observed in 3/10 cadavers (30%) in the AR group and 10/10 cadavers (100%) in the PEG group (P=0.003).
AR results in contrast medium mixture extravasation in all cadavers, but PEG altered the autopsy more severely. Both carrier substances result in specific substance-related artifacts and dependent opacification of the coronary arteries, but PEG is recommended for PMCTA exclusively with regard to diagnostic imaging.
本研究旨在比较一种基于聚乙二醇（PEG）的已建立的死后对比剂混合物与以醋酸林格溶液（AR）为基础的等渗晶体的混合物，两者均与水溶性碘对比剂混合用于死后 CT 血管造影（PMCTA），目的是避免尸检过程中尸体发生变化。
本研究纳入 20 具尸体；10 具进行 AR 的 PMCTA，10 具进行 PEG 的 PMCTA。对 PMCTA 图像进行分析，评估图像质量、血管对比模式和伪影。尸检评估肉眼、器官、血管和触觉改变。使用 Wilcoxon 秩和检验搜索两组间图像质量的差异。P<0.05 为差异有统计学意义。
AR 在右冠状动脉（P<0.001）内提供了极好的对比，但在左冠状动脉（P=0.008）内缺乏对比，而 PEG 则相反。与 AR 组相比，PEG 组右颈总动脉（P=0.03）、左颈总动脉（P=0.01）和左冠状动脉（P=0.008）的图像质量更好。升主动脉（P=0.65）、主动脉弓（P=0.09）、右大脑前动脉（P=0.17）、左大脑前动脉（P=0.08）、下腔静脉（P=0.07）和腹主动脉（P=0.08）之间无差异。AR 组所有 10/10（100%）例尸体均发生严重的外渗，但 PEG 组无一例发生（0/10；0%）（P<0.001）。尸检时，AR 组 10/10（100%）例尸体面部呈淡紫色变色，4/10（40%）例出现视觉改变，PEG 组 9/10（90%）例出现视觉改变（P=0.057）。AR 组 3/10（30%）例尸体触觉改变，PEG 组 10/10（100%）例尸体触觉改变（P=0.003）。
AR 导致所有尸体的对比剂混合物外渗，但 PEG 使尸检改变更严重。两种载体物质都会导致特定物质相关的伪影和冠状动脉的依赖性显影，但就诊断成像而言，推荐仅使用 PEG 进行 PMCTA。
