Progress in Medical Physics

Indexed in /covered by CAS, KoreaScience & DOI/Crossref:eISSN 2508-4453   pISSN 2508-4445

Table. 3.

Table. 3.

RED and EAN for DL-DECT images with wide and narrow collimation for Arr1

Material RED EAN


Theoretical value Wide collimation Narrow collimation Theoretical value Wide collimation Narrow collimation




Mean R.D (%) Mean R.D (%) Mean R.D (%) Mean R.D (%)
Lung inhale 1 0.200 0.196 −2.1 0.205 2.5 6.685 5.417 −19.0 6.863 2.7
Lung inhale 2 0.209 4.5 0.205 2.5 5.000 −25.1 6.117 −8.5
Lung exhale 1 0.496 0.536 8.1 0.537 8.3 7.231 6.156 −14.9 7.322 1.3
Lung exhale 2 0.519 4.7 0.537 8.3 8.200 13.4 7.375 2.0
Adipose 1 0.949 0.977 2.9 0.955 0.6 6.301 5.092 −19.2 6.325 0.4
Adipose 2 0.967 1.9 0.955 0.6 6.051 −4.0 6.253 −0.8
Breast 1 0.976 0.999 2.3 0.983 0.7 6.651 6.146 −7.6 6.720 1.0
Breast 2 0.962 −1.4 0.982 0.6 8.022 20.6 6.788 2.1
Muscle 1 1.040 1.033 −0.7 1.042 0.2 7.249 7.905 9.1 7.411 2.2
Muscle 2 1.086 4.5 1.043 0.3 5.981 −17.5 7.309 0.8
Liver 1 1.052 1.028 −2.3 1.051 −0.1 7.258 8.120 11.9 7.373 1.6
Liver 2 1.054 0.1 1.049 −2.3 7.620 5.0 7.377 1.6
Trabecular bone 1 1.117 1.103 −1.2 1.094 −2.1 9.833 9.849 0.2 9.757 −0.8
Trabecular bone 2 1.086 −2.8 1.091 −2.3 10.540 7.2 9.851 0.2
Dense bone 1 1.456 1.396 −4.1 1.422 −2.3 12.963 13.418 3.5 12.773 −1.5
Dense bone 2 1.447 −0.7 1.427 −2.0 13.180 1.7 12.703 −2.0

RED, relative electron density; EAN, effective atomic number; DL-DECT, dual-layer dual-energy computed tomography; Arr, arrangement.

R.D indicates the relative difference between theoretical values and the measured values.

Progress in Medical Physics 2021;32:165-71 https://doi.org/10.14316/pmp.2021.32.4.165
© 2021 Progress in Medical Physics