| Autor: |
Nick Jones, Thomas E. Milner, Moishe S. Kitai, Alexander P. Sviridov, Emil N. Sobol, Brian J. F. Wong |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
SPIE Proceedings. |
| ISSN: |
0277-786X |
| DOI: |
10.1117/12.308207 |
| Popis: |
We develop a theoretical model to calculate the temperature field and the size of modified structure area in cartilaginous tissue. The model incorporates both thermal and mass transfer in a tissue regarding bulk absorption of laser radiation, water evaporation from a surface and temperature dependence of diffusion coefficient. It is proposed that due to bound- to free-phase transition of water in cartilage heated to about 70 degrees Celsius, some parts of cartilage matrix (proteoglycan units) became more mobile. The movement of these units takes place only when temperature exceed 70 degrees Celsius and results in alteration of tissue structure (denaturation). It is shown that (1) the maximal temperature is reached not on the surface irradiated at some distance from the surface; (2) surface temperature reaches a plateau quicker that the maximal temperature; (3) the depth of denatured area strongly depends on laser fluence and wavelength, exposure time and thickness of cartilage. The model allows to predict and control temperature and depth of structure alterations in the course of laser reshaping and treatment of cartilage. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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