Chapter 9
Study of Optical Properties of Biotissues
by the Intracavity Laser Spectroscopy
Method
Abstract We describe a mathematic model for predicting the absorption spectrum
and dispersion of a section of a biological structure consisting of epidermis, upper
layer of the derma, blood, and lower layer of the derma and placed in the cavity of
an optical resonator. It should be noted that the biological structure was represented
by layers with different optical and geometrical parameters illuminated by a laser
beam.
9.1 Introduction
Optical methods (including traditional optical spectroscopy) based on analysis of
reflection, transmission, and fluorescence spectra of biological tissues play an important role among modern physical methods of analysis in biology and medicine. The
most effective methods that make it possible to study processes in complex biological systems are optical intracavity techniques. The application of intracavity laser
spectroscopy makes it possible to obtain more exact estimates of optical parameters
of the medium, which cannot be detected by conventional methods. Optical methods
make it possible to analyze processes without violating (modifying) living structures in complex biosystems. However, the application of these methods requires
the development of appropriate mathematical models for better understanding the
process of interaction of a laser beam with a biological object and for extending
potentialities, reliability, and availability of optical technologies, which would make
it possible to theoretically predict electrophysical parameters as characteristics of the
structural state of biological tissues (including human derma). The determination of
optical indices of a biological tissue is a complicated problem due to the complex
and heterogeneous structure of the tissue itself. Modern techniques for determining
optical parameters of biosystems involve the solution of the inverse scattering problem for various theoretical models such as the Monte Carlo method [1, 8], diffusion
approximation [2–4], and KubelkaMunk method of flow models [5–7].
In this study, mathematical model is constructed, which makes it possible to
vary electrophysical and geometrical parameters (layer thickness) of the section of
a biological tissue being modeled and to represent the result in the form of a graph
© Springer International Publishing AG, part of Springer Nature 2018
K. Kulikov and T. Koshlan, Laser Interaction with Heterogeneous
Biological Tissue, Biological and Medical Physics, Biomedical Engineering,
https://doi.org/10.1007/978-3-319-94114-1_9
153
Study of Optical Properties of Biotissues
by the Intracavity Laser Spectroscopy
Method
Abstract We describe a mathematic model for predicting the absorption spectrum
and dispersion of a section of a biological structure consisting of epidermis, upper
layer of the derma, blood, and lower layer of the derma and placed in the cavity of
an optical resonator. It should be noted that the biological structure was represented
by layers with different optical and geometrical parameters illuminated by a laser
beam.
9.1 Introduction
Optical methods (including traditional optical spectroscopy) based on analysis of
reflection, transmission, and fluorescence spectra of biological tissues play an important role among modern physical methods of analysis in biology and medicine. The
most effective methods that make it possible to study processes in complex biological systems are optical intracavity techniques. The application of intracavity laser
spectroscopy makes it possible to obtain more exact estimates of optical parameters
of the medium, which cannot be detected by conventional methods. Optical methods
make it possible to analyze processes without violating (modifying) living structures in complex biosystems. However, the application of these methods requires
the development of appropriate mathematical models for better understanding the
process of interaction of a laser beam with a biological object and for extending
potentialities, reliability, and availability of optical technologies, which would make
it possible to theoretically predict electrophysical parameters as characteristics of the
structural state of biological tissues (including human derma). The determination of
optical indices of a biological tissue is a complicated problem due to the complex
and heterogeneous structure of the tissue itself. Modern techniques for determining
optical parameters of biosystems involve the solution of the inverse scattering problem for various theoretical models such as the Monte Carlo method [1, 8], diffusion
approximation [2–4], and KubelkaMunk method of flow models [5–7].
In this study, mathematical model is constructed, which makes it possible to
vary electrophysical and geometrical parameters (layer thickness) of the section of
a biological tissue being modeled and to represent the result in the form of a graph
© Springer International Publishing AG, part of Springer Nature 2018
K. Kulikov and T. Koshlan, Laser Interaction with Heterogeneous
Biological Tissue, Biological and Medical Physics, Biomedical Engineering,
https://doi.org/10.1007/978-3-319-94114-1_9
153