Mathematical modeling of radiation fields in biological tissues: the definition of the brightness temperature for the diagnosis

The article contains the results of modeling of temperature fields and radiation fields in biological tissues. Experiments aimed at improving the efficiency of medical diagnosis of cancer. Diagnosis is made by microwave radiometry. The antenna is located at various points in the measurement. Joint integration of unsteady heat transfer equations and the Maxwell equation is the basis of the model. Our computer models take into account a realistic geometric structure of the breast. The mammary gland consists of lobules, outlet streams, adipose tissue blood flow. Each biological tissue is characterized by different values of the physical parameters. The temperature is calculated in the time of adaptation modeling object to the external environment. The time for establishing a quasi-stationary temperature field is equal to 30 minutes. Time depends weakly on the internal structure of healthy tissue. This work aims to study the features of the dynamics of the temperature inside the breast on the basis of computational experiments simulating the temperature measurement process during medical diagnosis. The temperature distribution in the biological tissue is formed by complex heat transfer processes in a highly inhomogeneous medium in the presence of heat sources associated with blood flow as a result of heat generation of physiological processes. The presence of malignant tumors leads to a substantial transfer of heat within the tissue restructuring. The basis of microwave radiometry method is the measurement of the socalled brightness temperature using a special antenna that detects the electric field distribution in biological tissues. And the resulting temperature is the result of a certain averaging temperature in a certain volume. In this paper, the results of calculations of temperature are discussed for the different volume values.