• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

1997 Fiscal Year Final Research Report Summary

Evaluation of scatter radiation and restoration of reconstructed images of 3D X-ray cone-beam CT scanner

Research Project

Project/Area Number 07650063
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Applied physics, general
Research InstitutionKyoto Institute of Technology

Principal Investigator

NAKAMORI Nobuyuki  Kyoto Institute of Technology, Faculty of Engineering and Design, Associate Professor, 工芸学部, 助教授 (20107353)

Project Period (FY) 1995 – 1997
Keywords3D CT / cone-beam CT / scattered radiation / image processing / wavelet transform / multiresolution analysis / antidiffusion equation
Research Abstract

Cone-beam computed tomography (CT) has some advantages that it can make a three-dimensional (3D) image in shorter time and with higher resolution in longitudinal direction of body than the helical CT scanner. However, because large amount of scatter radiation is included in 2D projection data, the quality of reconstructed image is worse and cupping artifacts appear in CT images. In this study, we have tried to improve the quality of reconstructed images and obtained the following results :
1.Using Monte Carlo simulation, we analyzed quantitatively the intensity distribution of scatter radiation on 2D projection data. From these simulation data, we have evaluated the dependence of scatter radiation on 3D reconstructed images.
2.Simulation results showed that intensity distribution of incident x-ray were controlled primary radiation on detector to be uniform, the scattered radiation included in projection data were decrease. Then, we reconstructed 3D CT images using a bow-tie flitter, which controlled the incident x-ray distribution and confirmed that the image quality of CT images improved.
3.We have improved the quality of CT images using image processing techniques, such as multiresolution analysis of wavelet transform, antidiffusion equation model and software correction with scattered distribution. These techniques were very useful to improve the quality of reconstructed image degraded by scatter radiation. Especially, usage of the weighting factors which were obtained from multiresolution analysis, we could reconstruct the CT images without any extra computing time and improve the image quality.
We Confirm our results are effective to make the cone-beam CT scanner in practical use.

  • Research Products

    (12 results)

All Other

All Publications (12 results)

  • [Publications] 中森 伸行: "コーンビーム型三次元CT装置の再構成画像への散乱線の影響" 医用画像情報学会雑誌. 12. 91-99 (1995)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] K.INOUE: "Software correction for scattered x-ray on cone-beam CT images" Journal of Imaging Science and Technology. 39. 319-323 (1995)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] 須藤 透: "3次元CTスキャナでの散乱X線の計算機シミュレーション" 医用画像情報学会雑誌. 13. 20-26 (1996)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] N.NAKAMORI: "Study on reconstructed image of 3D cone-beam CT scanner" SPIE Proceedings. 2708. 696-705 (1996)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Q.LI: "Antidiffusion and restoration for Gaussian blurred images" IEEE International Conference on Image Processing. 2. 238-241 (1997)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] N.NAKAMORI: "Image restoration of cone-beam CT images using wavelet transform" SPIE Proceedings. 3338(in press). (1998)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] N.NAKAMORI: "Effects of scattered x-ray on cone-beam 3-D CT images" Medical Imaging and Information Sciences. 12. 91-99 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] K.INOUE: "Software correction for scattered x-rays on cone-beam CT images" Jurnal of Imaging Science and Technology. 39. 319-323 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] T.SUDOU: "Computer simulation of scatter x-ray on 3-D CT scanner" Medical Imaging and Information Sciences. 13. 20-26 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] N.NAKAMORI: "Study on reconstructed image of 3D cone-beam CT scanner" SPIE Proceedings. 2707. 696-705 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Q.LI: "A multiscale antidiffusion aproach for Gaussian blurred images" IEEE International Conference on Image Processing. 2. 238-241 (1998)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] N.NAKAMORI: "Image restoration of cone-beam CT images using wavelet transform" SPIE Proceedings. 3338, (in press). (1998)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 1999-03-16  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi