| The first advantage of X-ray is its ability of penetration. Therefore, it is used in internal observation of human body. X-ray uses the principle of the shadowgraph using the different absorption of each tissue. However, absorption difference between the cancer tissue and the normal tissue is very small. When the cancer tissue is not big enough, the absorption contrast does not rise. Thus, cancer in early stage is hard to be detected. To develop a method to detect the cancer tissue in early stage, using the other properties of x-ray like phase, refraction, scattering, fluorescence and so on should be good. In this 5, 6 years of research, the principle used in this research is the refraction. The amount of はずれin x-ray refraction rate is very small(10e-6~10e-7). As a result, confirmation of refraction is not easy compare to visible light. However, by using x-ray optical system (double-crystal arrangement which uses silicon monocrystal) the refraction is distinguishable.。
1 or 2 pieces of roentgenograms or CT 3-D images are taken when we have a medical checkup. Therefore the development of CT algorithm corresponding to refraction principle which replaces the old CT base on the absorption principle is required because CT image is also desired in the medical site. Furthermore, we are challenging to develop an algorithm on reducing radiation exposure dose which is requested in clinical site.
Tomographic Reconstruction Based on X-Ray Refraction
Masami Ando, Hiroshi Sugiyama, Tetsuya Yuasa
Phys. Lett. 86 (2005) 124105-1~124105-3.
of Computed Tomographic Reconstruction of Cracks from the X-ray Refraction
Masami Ando, Hiroshi Sugiyama, Eiko Hashimoto
Appl. Phys. 44, Part 2, No.3A,
application of x-ray refraction based computed tomography to a biomedical
Eiko Hashimoto, Anton
Maksimenko, Hiroshi Sugiyama, Kazuyuki Hyodo, Daisuke Shimao, Yoshinori Nishino,
Tetsuya Ishikawa, Tetsuya Yuasa, Koichi Mori and Masami Ando
Science 23 (2006) 1-5.
Filtered Diffraction Micro-Tomography by Coherent Hard X-rays for Cell Imaging:
Theoretical and Numerical Studies of the Imaging and Reconstruction
Tetsuya Yuasa, Hiroshi Sugiyama, Zhong Zhong, Anton Maksimenko, F. Avraham
Dilmanian, Takao Akatsuka, Masami Ando
JOSA 22 (2005) 2622-2634.
2D and 3D
Visualization of Ductal Carcinoma in situ (DCIS) due to X-Ray Refraction
Masami Ando, Anton Maksimenko, Tetsuya Yuasa, Eiko Hashimoto, Katsuhito
Yamasaki, Chiho Ohbayashi, Hiroshi Sugiyama, Kazuyuki Hyodo, Tatsuro Kimura,
Hiroyasu Esumi, Takao Akatsuka, Gang Li,
Ei Ueno, Hiroko Bando, Shu Ichihara,
Tokiko Endo, Noriyuki Moriyama and Hisahide NishinoBioimages
14 (2006) 1-8.
Region Tomographic Reconstruction of the Refractive-index Gradient Vector Field:
Imaging Principles and Comparisons with Diffraction-Enhanced-Imaging-Based
Tetsuya Yuasa, Anton Maksimenko, Eiko Hashimoto, Hiroshi Sugiyama, Kazuyuki
Hyodo, Takao Akatsuka, Masami Ando
Letters 31 No.12 (2006) 1818-1820.