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Journal of the Korean Physical Society

, Volume 72, Issue 4, pp 539–544 | Cite as

Enhancement in the kV Portal Image Contrast Using Depth Normalization for Accurate Patient Localization

  • Hosang Jeon
  • Hanbean Youn
  • Jiho NamEmail author
  • Jayoung Lee
  • Juhye Lee
  • Dahl Park
  • Wontaek Kim
  • Yongkan Ki
  • Donghyun Kim
  • Ho Kyung Kim
Article

Abstract

The X-ray imaging modality has played an important role in the daily verification of a patient’s position for accurate radiation treatment (RT), especially in modern RT techniques that require highly precise patient localization. Although cone-beam computer tomography (CBCT) has already been introduced to the RT field, two-dimensional (2D) X-ray portal imagers have been more widely used than CBCT for the daily check of patient localization owing to the lower patient exposure and time consumption. However, the 2D imager practically provide a lower bone-tissue contrast than CBCT. Thus, we propose a method that enhances the image contrast of daily acquired 2D images by using just one CBCT scan during an entire RT course. This method operates on the basis of the depth normalization (DN) technique and requires no artificial data manipulation such as image post-processing filters. We implemented the algorithm for the portal images of a cylindrical phantom and three patients. From DN results, the image contrast for the phantom and the patients increased by factors of 26.3 and 13.4 on average, and their contrast-to-noise ratios were maintained at differences of 8.6% and 7.7% on average, respectively. Moreover, the DN method provided a stronger contrast enhancement at lower doses that could suppress the imaging exposure and thus improve the patient’s safety. Therefore, the verification of RT patient localization is expected to be performed more efficiently and accurately by using the DN method.

Keywords

kV image contrast Patient localization Radiotherapy Depth normalization 

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References

  1. [1]
    P. Kallman, B. Lind, A. Eklof and A. Brahme, Phys. Med. Biol. 33, 1291 (1988).CrossRefGoogle Scholar
  2. [2]
    C. X. Yu, Phys. Med. Biol. 40, 1435 (1995).CrossRefGoogle Scholar
  3. [3]
    C. X. Yu, M. J. Symons, M. N. Du, A. A. Martinez and J. W. Wong, Phys. Med. Biol. 40, 769 (1995).CrossRefGoogle Scholar
  4. [4]
    D. A. Jaffray, J. H. Siewerdsen, J. W. Wong and A. A. Martinez, Int. J. Radiat. Oncol. Biol. Phys. 53, 1337 (2002).CrossRefGoogle Scholar
  5. [5]
    D. Gur, M. Deutsch, C. R. Fuhrman, P. A. Clayton, J. C. Weiser, M. S. Rosenthal and A. G. Bukovitz, Med. Phys. 16, 132 (1989).CrossRefGoogle Scholar
  6. [6]
    E. Meyer, R. Raupach, M. Lell, B. Schmidt and M. Kachelriess, Med. Phys. 37, 5482 (2010).CrossRefGoogle Scholar
  7. [7]
    M. R. Paudel, M. Mackenzie, B. G. Fallone and S. Rathee, Med. Phys. 40, 081701 (2013).CrossRefGoogle Scholar
  8. [8]
    R. L. Siddon, Med. Phys. 12, 252 (1985).CrossRefGoogle Scholar

Copyright information

© The Korean Physical Society 2018

Authors and Affiliations

  • Hosang Jeon
    • 1
  • Hanbean Youn
    • 1
  • Jiho Nam
    • 1
    Email author
  • Jayoung Lee
    • 1
  • Juhye Lee
    • 1
  • Dahl Park
    • 2
  • Wontaek Kim
    • 2
  • Yongkan Ki
    • 2
  • Donghyun Kim
    • 2
  • Ho Kyung Kim
    • 3
  1. 1.Department of Radiation Oncology and Research Institute for Convergence of Biomedical Science and TechnologyPusan National University Yangsan HospitalYangsanKorea
  2. 2.Department of Radiation OncologyPusan National University HospitalBusanKorea
  3. 3.School of Mechanical Engineering and Center for Advanced Medical Engineering ResearchPusan National UniversityBusanKorea

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