Modelling of thermal damage in laser irradiated tissue

Abstract

Abstract. In the paper the numerical analysis of thermal processes proceeding in the 2D homogeneous biological tissue subjected to laser irradiation is presented. In particular, the influence of necrotic changes in tissue on the values of the perfusion coefficient and effective scattering coefficient are discussed. The transient heat transfer is described by the bioheat transfer equation in the Pennes formulation. As a model of light distribution in tissue, the first-order scattering approach has been used. At the stage of numerical realization the 1 st scheme of the boundary element method has been applied.

Modelling of biological tissue damage process with application of interval arithmetic

“…The modelling of the tissue thermal damage process also includes a number of other problems, e.g. methods of taking into account changes in parameter values caused by the degree of tissue damage (Jasiński, 2015(Jasiński, , 2018. Further work related to the application of directed interval arithmetic in this area could concern these issues or the problems related with the use of interval numbers in other algorithms related to thermal damage (Jasiński, 2015;Mochnacki and Piasecka, 2013).…”

“…methods of taking into account changes in parameter values caused by the degree of tissue damage (Jasiński, 2015(Jasiński, , 2018. Further work related to the application of directed interval arithmetic in this area could concern these issues or the problems related with the use of interval numbers in other algorithms related to thermal damage (Jasiński, 2015;Mochnacki and Piasecka, 2013). Because the interval arithmetic is a method developed by mathematicians in order to put bounds on rounding errors and measurement errors in mathematical computation, it could also be a useful approach to the modelling of various problems of bioheat transfer.…”

“…It is also worth noting that tissue parameters may have different values depending on their degree of thermal damage. For example, the value of the scattering coefficient of tissue during the tissue damage process increases several times, what could be observed as "whitening" of the tissue (Jasiński, 2015).…”

Modelling of thermal damage process in soft tissue subjected to laser irradiation

“…where c B [Jm -3 K -1 ] is the volumetric specific heat of blood, T B corresponds to the arterial temperature while w(Ψ) [s -1 ] is the perfusion coefficient defined as [8,9,17] Modelling of thermal damage process in soft tissue subjected to laser irradiation 31 ( )…”

“…The most popular model of the tissue damage process is the Arrhenius injury integral [12][13][14][15][16]. This approach basically refers only to the irreversible tissue damage, however, there are models that allow one to take into account the withdrawal of tissue injury in the case of temporary, small local increasing of temperature [17].…”