Department of Life Sciences and Health, Oslo Metropolitan University, Box 4, St. Olavs plass, 0130, Oslo, Norway.
The Department of Diagnostic Physics, Oslo University Hospital, Bygg 20, Gaustad Sykehus, Box 4959 Nydalen, 0424, Oslo, Norway.
Eur Radiol Exp. 2021 Jun 23;5(1):24. doi: 10.1186/s41747-021-00224-2.
The aim of this study was to quantitatively benchmark iodine imaging across specific virtual monoenergetic energy levels, iodine maps and virtual non-contrast images with different phantom sizes and iodine concentrations, using a rapid switching dual-energy CT (DECT) and a dual source DECT, in order to investigate accuracy and potential differences between the technologies.
Solutions of iodine contrast (10, 20, 30, 50, and 100 mg/mL), sterile water and saline were scanned in a phantom on a rapid switching single-source and dual-source DECT scanners from two different vendors. The phantom was equipped with polyurethane rings simulating three body sizes. The datasets were reconstructed in virtual monoenergetic energy levels (70, 80, 90, 100, 110, 120, 130, and 140 keV), virtual non-contrast images and iodine maps. HU and iodine concentrations were measured by placing ROIs in the iodine solutions.
The iodine concentrations were reproduced with a high degree of accuracy for the single-source DECT (1.8-9.0%), showing a slight dependence on phantom size. The dual source DECT technique showed deviant values (error -33.8 to 12.0%) for high concentrations. In relation to the virtual non-contrast measurements, the images from both vendors were affected by the iodine concentration and phantom size (-127.8 to 539.1 HU). Phantom size did not affect the calculated monoenergetic attenuation values, but the attenuation values varied between the scanners.
Quantitative measurements of post-processed images are dependent on the concentration of iodine, the phantom size and different technologies. However, our study indicates that the iodine maps are reliable for quantification of iodine.
本研究旨在使用快速切换双能 CT（DECT）和双源 DECT，针对不同的体模大小和碘浓度，对特定虚拟单能量水平、碘图和虚拟非对比图像进行碘成像定量基准测试，以探究两种技术的准确性和潜在差异。
在来自两个不同供应商的快速切换单源和双源 DECT 扫描仪上的体模中扫描碘对比剂（10、20、30、50 和 100mg/mL）、无菌水和生理盐水溶液。该体模配备了模拟三种体型的聚氨酯环。数据集以虚拟单能量水平（70、80、90、100、110、120、130 和 140keV）、虚拟非对比图像和碘图进行重建。通过在碘溶液中放置 ROI 来测量 HU 和碘浓度。
单源 DECT 可高度准确地再现碘浓度（1.8-9.0%），表现出对体模大小的轻微依赖性。双源 DECT 技术对于高浓度显示出偏差值（误差为-33.8 至 12.0%）。与虚拟非对比测量相比，来自两个供应商的图像均受到碘浓度和体模大小的影响（-127.8 至 539.1HU）。体模大小不影响计算的单能量衰减值，但衰减值在扫描仪之间有所差异。
后处理图像的定量测量取决于碘浓度、体模大小和不同的技术。然而，我们的研究表明碘图可用于碘的定量。
