Proceedings of the Korean Society of Medical Physics Conference (한국의학물리학회:학술대회논문집)

Korean Society of Medical Physics (한국의학물리학회)
권호 표지

Development of a Brain Phantom for Multimodal Image Registration in Radiotherapy Treatment Planning

  • H. S. Jin (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • T. S. Suh (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • R. H. Juh (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • J. Y. Song (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • C. B. Y. Choe (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • Lee, H .G. (Dept. of Biomedical Engineering, The Catholic University of Korea) ;
  • C. Kwark (Dept. of Biomedical Engineering, The Catholic University of Korea)
  • Published : 2002.09.01
Download PDF
⟨ Previous Next ⟩

Abstract

In radiotherapy treatment planning, it is critical to deliver the radiation dose to tumor and protect surrounding normal tissue. Recent developments in functional imaging and radiotherapy treatment technology have been raising chances to control tumor saving normal tissues. A brain phantom which could be used for image registration technique of CT-MR and CT-SPECT images using surface matching was developed. The brain phantom was specially designed to obtain imaging dataset of CT, MR, and SPECT. The phantom had an external frame with 4 N-shaped pipes filled with acryl rods, Pb rods for CT, MR, and SPECT imaging, respectively. 8 acrylic pipes were inserted into the empty space of the brain phantom to be imaged for geometric evaluation of the matching. For an optimization algorithm of image registration, we used Downhill simplex algorithm suggested as a fast surface matching algorithm. Accuracy of image fusion was assessed by the comparison between the center points of the section of N-shaped bars in the external frame and the inserted pipes of the phantom and minimized cost functions of the optimization algorithm. Technique with partially transparent, mixed images using color on gray was used for visual assessment of the image registration process. The errors of image registration of CT-MR and CT-SPECT were within 2mm and 4mm, respectively. Since these errors were considered within a reasonable margin from the phantom study, the phantom is expected to be used for conventional image registration between multimodal image datasets..

Keywords