| Project/Area Number |
13670949
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Radiation science
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| Research Institution | Nagasaki university |
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Principal Investigator |
ITO Masako Department of Radiology, Nagasaki University School of Medicine, Assistant Professor, 医学部附属病院, 講師 (10193517)
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| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Kuniaki Graduate School of Biomedical Sciences, Nagasaki University, Professor, 大学院・医歯薬学総合研究科, 教授 (80039536)
KOGA Aoi. Research and Development Center for Higher Education, Nagasaki University, Assistant Professor, 大学教育機能開発センター, 講師 (60284709)
YAMAGUCHI Akira Graduate School of Biomedical Sciences, Nagasaki University, Professor, 大学院・医歯薬学総合研究科, 教授 (00142430)
古賀 揚維 長崎大学, 工学部, 助手
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| Project Period (FY) |
2001 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2002: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2001: ¥3,300,000 (Direct Cost: ¥3,300,000)
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| Keywords | bone microarchitecture / mechanical property / synchrotron radiation CT / synchrotron X-ray CT / micro-CT / osteoporosis |
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| Research Abstract |
1) There are two different types of anti-osteoporotic agents ; anti-resorptive agent and bone-formative agent. The effect of the former agent was shown to preserve trabecular connectivity, while that of the latter was to thicken trabeculae in the ovariectomized rats.
2) According to the meta-analysis from several clinical trials of antiresorptive agents looking at the relative risk of vertebral fractures against the average change in bone mineral density (BMD) for each trial, most of the effect of treatment was explained by an 8% increase in spinal BMD, which produced a 41% risk reduction. However, there is no proofs nor explanations. Finite element analysis (FEA) demonstrated that this effect of anti-resorptive agent to preserve connectivity seemed to increase bone strength with small increase in BMD.
3) Our micro-FEA system was validated to assess the mechanical properties of bone, including the individual properties of the spongiosa and cortex, in the osteoporotic rat model. We found that the mechanical property of each component had a significant relationship with the respective bone mass, volume or structure. While trabecular microstructure has a significant relationship with bone strength, in the OVX bone with deteriorated trabecular microstructure, the strength mainly depended on the cortical component.
4) SR-CT seems to be a useful tool for delineating trabecular surfaces, evaluating bone mineralization, and for revealing precise trabecular structure. We could visualize and quantify the calcium density using the different mass attenuation coefficients depending on energy between calcium and carbon. We calculated the calcium density according to the formula : CT value= mca/ro x rca+mc/ro x rc
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