Dual-energy computed tomography of the head: A phantom study assessing axial dose distribution, eye lens dose, and image noise level

Kosuke Matsubara, Hiroki Kawashima, Takashi Hamaguchi, Tadanori Takata, Masanao Kobayashi, Katsuhiro Ichikawa, Kichiro Koshida

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The aim of this study was to propose a calibration method for small dosimeters to measure absorbed doses during dual- source dual-energy computed tomography (DECT) and to compare the axial dose distribution, eye lens dose, and image noise level between DE and standard, single-energy (SE) head CT angiography. Three DE (100/Sn140 kVp 80/Sn140 kVp, and 140/80 kVp) and one SE (120 kVp) acquisitions were performed using a second-generation dual-source CT device and a female head phantom, with an equivalent volumetric CT dose index. The axial absorbed dose distribution at the orbital level and the absorbed doses for the eye lens were measured using radiophotoluminescent glass dosimeters. CT attenuation numbers were obtained in the DE composite images and the SE images of the phantom at the orbital level. The doses absorbed at the orbital level and in the eye lens were lower and standard deviations for the CT attenuation numbers were slightly higher in the DE acquisitions than those in the SE acquisition. The anterior surface dose was especially higher in the SE acquisition than that in the DE acquisitions. Thus, DE head CT angiography can be performed with a radiation dose lower than that required for a standard SE head CT angiography, with a slight increase in the image noise level. The 100/Sn140 kVp acquisition revealed the most balanced axial dose distribution. In addition, our proposed method was effective for calibrating small dosimeters to measure absorbed doses in DECT.

Original languageEnglish
Title of host publicationMedical Imaging 2016
Subtitle of host publicationPhysics of Medical Imaging
EditorsDespina Kontos, Joseph Y. Lo, Thomas G. Flohr
PublisherSPIE
ISBN (Electronic)9781510600188
DOIs
Publication statusPublished - 01-01-2016
EventMedical Imaging 2016: Physics of Medical Imaging - San Diego, United States
Duration: 28-02-201602-03-2016

Publication series

NameProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume9783
ISSN (Print)1605-7422

Other

OtherMedical Imaging 2016: Physics of Medical Imaging
CountryUnited States
CitySan Diego
Period28-02-1602-03-16

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All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Atomic and Molecular Physics, and Optics
  • Radiology Nuclear Medicine and imaging

Cite this

Matsubara, K., Kawashima, H., Hamaguchi, T., Takata, T., Kobayashi, M., Ichikawa, K., & Koshida, K. (2016). Dual-energy computed tomography of the head: A phantom study assessing axial dose distribution, eye lens dose, and image noise level. In D. Kontos, J. Y. Lo, & T. G. Flohr (Eds.), Medical Imaging 2016: Physics of Medical Imaging [978347] (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. 9783). SPIE. https://doi.org/10.1117/12.2216650