Studying the interaction between light and biological tissues is extremely important for the development of new optical diagnostic and therapeutic techniques. In order to accelerate and improve the development of the latter, there is an increasing need to develop tissue phantoms that sufficiently mimic the optical, thermal and mechanical properties of the target biological tissues. A number of such tissue phantoms are presented in the literature, from liquid to solid, where each of them has advantages and disadvantages for selected applications. The advantage of solid phantoms is the temporal stability of physical properties, easy storage and design. Silicone phantoms based on SiliGlass polymer are used in the medical physics group for optimization and validation of new optical imaging techniques.
As part of the master's thesis, we compare the optical (reflectivity, transmittance) and thermal properties (specific heat, thermal conductivity) of solid SiliGlass phantoms. The optical properties are measured with hyperspectral imaging and spatially resolved spectroscopy and the Fourier transform infrared spectroscopy (FTIR) method, while the thermal properties are compared with the differential scanning calorimetry (DSC) technique and through thermal excitation of a sample with known optical properties with laser pulses. We develop appropriate tools for analyzing measurements and comparing results obtained with different techniques.
The final result of the master's thesis is the optical and thermal characterization of different SiliGlass tissue phantoms according to the amount of absorber and scatterer in the substance. This kind of knowledge will enable the use of such phantoms for the development and optimization of various laser therapeutic interventions.
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