Evaluation Mechanical Properties of Artificial Skin Induced by Ionized Radiation Using Optical Polarized Heterodyne Laser Scanning Microscope

• Main Authors: Tung-Sheng Hsieh, 謝東昇
• Other Authors: Chien Chou
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/66852714083369145147

碩士 === 國立陽明大學 === 放射醫學科學研究所 === 91 === Quantitative measurement of tissue radiation damage in radiation therapy is important while optimizing the therapeutic treatment. Ionized radiation induces homogenization of the extracellular matrix that is synthesized by fibroblast and the randomization of the orientation of the collagen fibers in dermis. If the dermis were exposed under ionized radiation, a thermal elastic shear wave (TESW), which propagates in dermis, would become harmonic wave. Otherwise, an anharmonic wave is expected because of inhomogeneous and anisotropic properties, which include rigid modulus and density of dermis. In this study, a polarized optical heterodyne Michelson interferometer was setup in order to measure the transverse displacement of TESW in dermis. In the mean time, the propagation mode of the TESW in dermis was analyzed. The detected sensitivity of the displacement was 1 nm, and the dynamic range was 150 nm in this arrangement. The lowest dose that able to be detected usingγandχ-ray on treat artificial skin was 1 cGy. In experiment, the linearity between absorbed dose and oscillation frequency of TESW in the range of 1 cGy to 500 cGy was discovered. Then a novel method to determine the absorbed dose has been observed quantitatively in terms of the mechanical properties from changes of skin structures. In addition, the linearity of absolute dose using this method can provide the preferential data in clinical radiation therapy. Also, we have demonstrated that the artificial skin can be developed potentially to be a biological dosimeter.