Phantom for optical imaging.

• Main Author: Khor, Bo Yang.
• Other Authors: Lee Kijoon
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Chemical engineering::Industrial photochemistry
• Online Access: http://hdl.handle.net/10356/16443
• Institution: Nanyang Technological University

In diagnostic and therapeutic applications of light in medicine, it is vital to evaluate the optical properties of biological tissue. The ultimate goal of this project is to develop a sample which closely mimics the human tissue. These so called “phantom” plays a crucial role in evaluating any new diagnostic or therapeutic modality. In order to do so, the optical properties for human tissue must be recognized. Firstly, human body have the refractive index, n = 1.33 ~ 1.55. The approximation value of absorption coefficient is 0.05 cm-1 while the reduced scattering coefficient is 8.0 cm-1 for human breast. Three solid phantoms will be developed in this project. They are RTV silicone phantom, polyester resin phantom and gel phantom. Room temperature vulcanizing (RTV) silicone has the refractive index of 1.4 which is quite similar to human tissue. Another consideration for phantoms main component is polyester resin. It has quite similar refractive index (1.50). Carbon black is used as absorber, contributes to the value of absorption coefficient while Titanium (IV) Oxide is used as scattering agent, will determine the value for reduced scattering coefficient. Ocean Optics USB-4000 is the device used to obtain the absorbance spectrum data and light intensity spectrum. Then by applying the Green Function of photon diffusion equation in semi-infinite space, the absorption coefficient can be easily determined by taking the assumption of scattering coefficient of phantom from the literature. In later part of experiment, silicone breast mold and phantom were developed.