The Clinical Usefulness of Water/Iodine Material Density Measured by DE-CT

Abstract

Dual energy-computed tomography (DE-CT) can discriminate between materials using the material density obtained by two types of X-ray energies. This study investigated the characteristics of the water density value (WDV) used as a prognostic indicator. WDV with any contrast medium concentration was measured using a bottled diluted contrast medium. In addition, we studied retrospective reviews of 117 patients who underwent DE-CT between 2013 and 2018 and compared them with WDVs before and after contrast enhancement (CE). The WDVs were obtained from the abdominal aorta and superior vena cava. In the ex-vivo study, the WDV decreased slightly by of 0-10% contrast medium concentration, however, it increased gradually above 10%. The number of patients whose WDV of the CT image increased after CE-CT were 28 in the arteries and 50 in the veins. The results suggested that the concentration of the contrast medium was over 10% in arteries and veins. The differences between WDVs in arteries and veins obtained from CT images were very small, with or without CE. Therefore, it was revealed that WDV was less affected by the difference in arteries and veins, or by using contrast medium.