Energetic analysis of composite of filter for the low contrast improvement of IVR

IVR低对比度改善滤波器组合的能量分析

• 批准号: 11670876
• 负责人: KOSHIDA Kichiro
• 金额: $ 2.11万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11670876/
• 关键词: IVR; low contrast improvement; multi-filter; K吸収端; 付加フィルタ

To image the human tissue in noninvasion, X-rays, ultrasonic waves and MRI are used. The radiological diagnosis using the difference between linear attenuation coefficients which differs by the property of the organization is the most general. The recogntition of the change and deformation of the aspect are easy, when it was imaged, because the linear attenuation coefficient is greatly different on it in bones and soft tissue and air inclusion organ solution muscular tissue. In the human tissue, the exposure condition is examined, because the difference of linear attenuation coefficient lowers on the delicate change of muscular tissue and soft tissue as subjective contrast small. The difference of the linear attenuation coefficient increases if the effective energy is lowered in order to improve the subjective contrast. Then it is possible that the diagnosis is improved in large change. Then, the tube voltage is set high, and the low energy with many exposures using added filter is rem … More oved, and in addition, high energy component which does the contrast bad is absorbed. On this, it was reported that the filters of K absorption edues (around 20KeV) such as niobium, molybdenum, rhodium compared with the filters of aluminum, copper, and that the permeability of the high energy region is high, and that the decrease of the low energy region is large. Therefore, the optimum thickness analysis and the multiple filter of aluminum and copper seem to be necessity in the analysis in the high energy region. The results of these analysis are followed.1) Mix-Dp which is the most similar for the human tissue composition to the evaluation of the test object contrast when an X-ray spectrum from diagnostic X-ray apparatus is considered, should be used.2) The thickness of 0.001cm is adequate for the tungsten added filter in which the energy of the K absorption edge is high.3) The material of the atomic number which is lower than atomic number of the niobium is adequate, when the material in which the energy of the K absorption edge is low is used.4) The thickness is different by the scattered radiation content rate and γ of the film, when the material of the energy in which the K absorption edge is low is used. Less

为了对人体组织进行无创成像，X射线、超声波和MRI被使用。利用线性衰减系数之间的差异进行放射学诊断是最普遍的，其中线性衰减系数因组织的性质而异。由于骨、软组织与含气器官、溶解肌肉组织的线性衰减系数有很大差异，因此在成像时，很容易识别其形态的变化和变形。在人体组织中，由于主观对比度小，线性衰减系数的差异在肌肉组织和软组织的微妙变化上降低，因此检查曝光条件。如果为了改善主观对比度而降低有效能量，则线性衰减系数的差增大。因此，有可能在大的变化中提高诊断。然后，管电压设置高，低能量与许多曝光使用添加过滤器是rem ...更多信息 此外，吸收了影响对比度的高能量成分。关于这一点，据报道，与铝、铜的过滤器相比，铌、钼、铑等K吸收损耗（约20 KeV）的过滤器，高能区的磁导率高，低能区的磁导率下降大。因此，在高能区的分析中，铝和铜的最佳厚度分析和多重滤波器是必要的。这些分析的结果如下。1）当考虑来自诊断X射线设备的X射线光谱时，对于人体组织组成来说，Mix-Dp与测试对象对比度的评价最相似，0.001cm的厚度对于K吸收边能量较高的加钨滤光片是合适的当使用K吸收边的能量低的材料时，原子序数低于铌的原子序数的材料是合适的。4）膜的厚度因膜的散射辐射含量率和γ而不同，当使用K吸收边缘低的能量材料时，少

项目成果

Kichiro Koshida: "Correction of Measurement by Hy-Ge Detector for Incident Diagnostic X-ray Photons."Proceedings of the Second International Workship on EGS. Vol.1. 253-241 (2000)

Kichiro Koshida：“Hy-Ge 探测器对事件诊断 X 射线光子的测量校正。”第二届 EGS 国际研讨会论文集。

越田吉郎: "人体組織および人体組織等価物質における吸収線量変換係数の評価"金沢大学医学部保健学科紀要. 23・2. 57-64 (1999)

越田义郎：“人体组织和人体组织等效材料的吸收剂量转换系数的评估”金泽大学医学院健康科学系通报23・2（1999）。

Kichiro Koshida: "Correction of Measurement by HP-GE Detector for Incident Diagnostic X-ray PhotonS"Proceedings of the Second International Workshop on EGS. Vol.1. 235-241 (2000)

Kichiro Koshida：“HP-GE 探测器对事故诊断 X 射线光子的测量校正”第二届 EGS 国际研讨会论文集。