한국의학물리학회지:의학물리 (Progress in Medical Physics)

  • 제30권4호
  • /
  • Pages.160-166
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  • 2019
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  • 2508-4445(pISSN)
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  • 2508-4453(eISSN)
한국의학물리학회 (Korean Society of Medical Physics)
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Acceptance Test and Clinical Commissioning of CT Simulator

  • An, Hyun Joon (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Son, Jaeman (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Jin, Hyeongmin (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Sung, Jiwon (Department of Radiation Oncology, Seoul National University Hospital) ;
  • Chun, Minsoo (Department of Radiation Oncology, Seoul National University Hospital)
  • 투고 : 2019.12.13
  • 심사 : 2019.12.18
  • 발행 : 2019.12.31
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초록

This study examined the clinical use of two newly installed computed tomography (CT) simulators in the Department of Radiation Oncology. The accreditation procedure was performed by the Korean Institute for Accreditation of Medical Imaging. An Xi R/F dosimeter was used to measure the CT dose index for each plug of the CT dose index phantom. Image qualities such as the Hounsfield unit (HU) value of water, noise level, homogeneity, existence of artifacts, spatial resolution, contrast, and slice thickness were evaluated by scanning a CT performance phantom. All test items were evaluated as to whether they were within the required tolerance level. CT calibration curves-the relationship between CT number and relative electron density-were obtained for dose calculations in the treatment planning system. The positional accuracy of the lasers was also evaluated. The volume CT dose indices for the head phantom were 22.26 mGy and 23.70 mGy, and those for body phantom were 12.30 mGy and 12.99 mGy for the first and second CT simulators, respectively. HU accuracy, noise, and homogeneity for the first CT simulator were -0.2 HU, 4.9 HU, and 0.69 HU, respectively, while those for second CT simulator were 1.9 HU, 4.9 HU, and 0.70 HU, respectively. Five air-filled holes with a diameter of 1.00 mm were used for assessment of spatial resolution and a low contrast object with a diameter of 6.4 mm was clearly discernible by both CT scanners. Both CT simulators exhibited comparable performance and are acceptable for clinical use.

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피인용 문헌

  1. Basic Physical Principles and Clinical Applications of Computed Tomography vol.32, pp.1, 2019, https://doi.org/10.14316/pmp.2021.32.1.1
  2. Gold coated contact lens-type ocular in vivo dosimeter (CLOD) for monitoring of low dose in computed tomography: A Monte Carlo study vol.92, 2019, https://doi.org/10.1016/j.ejmp.2021.10.016