Three Dimensional Computer Program for Simulating Light Transport in Complex Geometries

Friday, October 28, 2011
Hall 1-2 (San Jose Convention Center)
Sina Bigdeli , National Science Foundation (NSF), Center for Biophotonics Science and Technology (CBST), Sacramento, CA
Stephen Lane, PhD , NSF Center for Biophotonics Science and Technology (CBST), Sacramento, CA
Amy Gryshuk, PhD , NSF Center for Biophotonics (CBST), Sacramento, CA
Dennis Matthews, PhD , NSF Center for Biophotonics, Sacramento, CA
Ken Turtelaub, PhD , Lawrence Livermore National Laboratory (LLNL), Livermore , CA
Light is used as the basis for a wide variety of medical diagnostics and therapies. To best understand the details of these applications, it is important to know how light moves through tissues. We have developed a new computer code that is capable of tracking the movement of laser light through tissues having complex geometries using a method known as Monte Carlo transport. In this ongoing study, we have written a computer program using the MATLAB 7 language that uses measured values of the absorption coefficient and reduced scattering coefficient for each type of tissue present in the problem under investigation. The program is capable of simulating complex 3D geometries consisting of solid geometric objects. The geometric model is described in a simple way by defining these solids rather than using the more complex conventional approach of surface definitions. The geometry is divided into zones that each represent a different tissue type. The tissue model is illuminated by laser light from a fiber optic. The fluence and absorption of light in each cell of a square volumetric mesh in which the geometry is embedded is then calculated and displayed in a color coded fashion. We will show results of simulations for different example geometries.