Chapter 10
Photon-Tissue Interaction Modelled
by Monte Carlo Method for Optimizing
Optoelectronic Sensor Concepts
Markus Hülsbusch and Vladimir Blazek
Abstract The Monte Carlo method is a well-established tool for the evaluation of
photon tissue interaction. Based on statistical sampling it allows exact prediction
of photon distribution while only requiring basic parameters of bio tissue. Different
virtual skin models from literature are evaluated, implemented and are also validated
by experimental measurements. A simulation tool has been developed, which is
capable of tracing and visualizing photon paths in the tissue. Different simulation
results like penetration depths, measurement volume, etc. can be quantified. Due to
increased processing power also dynamic simulations could be run. Here not only
a static simulation scenario is calculated, but it can be parameterized to optimize
different properties of the sensor. When the skin model is parameterized to varying
blood contents also vital functions like the heartbeat can be simulated. As a result,
the DC component and also the AC component of the sensor signal can be predicted,
as well as the tissue transillumination and sensor sensitivity in relation to the skin
depth.
10.1 Introduction
Optoelectronic sensor concepts are gaining importance in modern medicine. They are
working non-invasively and—if needed, also contact-less, allow cheap and flexible
measurements and are widely accepted by the patients. For the design and optimization of these sensors, the knowledge of photon-tissue interaction is essential. Monte
Carlo simulations are based on the method of statistical sampling for the solution of
quantitative problems. They were first introduced by Metropolis and Ulam in 1949 for
the prediction of neutron distributions in uranium [1]. In the presented optical domain
the interaction between photons and tissue is simulated by distribution functions of
the interaction processes and generation of random numbers. Light is considered as
M. Hülsbusch (B) · V. Blazek
Medical Information Technology, Helmholtz Institute for Biomedical Engineering, RWTH
Aachen University, Aachen, Germany
e-mail: perfusion.group@hia.rwth-aachen.de
© Springer Nature Singapore Pte Ltd. 2021
V. Blazek et al. (eds.), Studies in Skin Perfusion Dynamics,
Biological and Medical Physics, Biomedical Engineering,
https://doi.org/10.1007/978-981-15-5449-0_10
163
Photon-Tissue Interaction Modelled
by Monte Carlo Method for Optimizing
Optoelectronic Sensor Concepts
Markus Hülsbusch and Vladimir Blazek
Abstract The Monte Carlo method is a well-established tool for the evaluation of
photon tissue interaction. Based on statistical sampling it allows exact prediction
of photon distribution while only requiring basic parameters of bio tissue. Different
virtual skin models from literature are evaluated, implemented and are also validated
by experimental measurements. A simulation tool has been developed, which is
capable of tracing and visualizing photon paths in the tissue. Different simulation
results like penetration depths, measurement volume, etc. can be quantified. Due to
increased processing power also dynamic simulations could be run. Here not only
a static simulation scenario is calculated, but it can be parameterized to optimize
different properties of the sensor. When the skin model is parameterized to varying
blood contents also vital functions like the heartbeat can be simulated. As a result,
the DC component and also the AC component of the sensor signal can be predicted,
as well as the tissue transillumination and sensor sensitivity in relation to the skin
depth.
10.1 Introduction
Optoelectronic sensor concepts are gaining importance in modern medicine. They are
working non-invasively and—if needed, also contact-less, allow cheap and flexible
measurements and are widely accepted by the patients. For the design and optimization of these sensors, the knowledge of photon-tissue interaction is essential. Monte
Carlo simulations are based on the method of statistical sampling for the solution of
quantitative problems. They were first introduced by Metropolis and Ulam in 1949 for
the prediction of neutron distributions in uranium [1]. In the presented optical domain
the interaction between photons and tissue is simulated by distribution functions of
the interaction processes and generation of random numbers. Light is considered as
M. Hülsbusch (B) · V. Blazek
Medical Information Technology, Helmholtz Institute for Biomedical Engineering, RWTH
Aachen University, Aachen, Germany
e-mail: perfusion.group@hia.rwth-aachen.de
© Springer Nature Singapore Pte Ltd. 2021
V. Blazek et al. (eds.), Studies in Skin Perfusion Dynamics,
Biological and Medical Physics, Biomedical Engineering,
https://doi.org/10.1007/978-981-15-5449-0_10
163