Multipurpose Monte Carlo simulator for photon transport in turbid media

Proceeding of: 2009 IEEE Nuclear Science Symposium Conference Record (NSS/MIC), Orlando, Florida, 25-31 October 2009Monte Carlo methods provide a flexible and rigorous solution to the problem of light transport in turbid media, which enable approaching complex geometries for a closed analytical solution is not feasible. The simulator implements local rules of propagation in the form of probability density functions that depend on the local optical properties of the tissue. This work presents a flexible simulator that can be applied in multiple applications related to optical tomography. In particular, unlike previous codes, the simulator explicitly supports fluorescent-tissues and variance reduction and code parallelization techniques are implemented in order to speed up the execution with fluorochrome-labelled agents. The simulator is validated with simple geometries for which an analytical solution exists, as well as with an experimental polyester resin based optical phantom.This work was supported in part by the Ministry of Science and Innovation under projects TEC2008-06715 and TEC2007-64731/TCM and by the EU’s 7th Frame Programme under contract HEALTH-F5-2008-20179

Optical projection tomography as a tool for 3D imaging of hydrogels

An Optical Projection Tomography (OPT) system was developed and optimized to image 3D tissue engineered products based in hydrogels. We develop pre-reconstruction algorithms to get the best result from the reconstruction procedure, which include correction of the illumination and determination of sample center of rotation (CoR). Existing methods for CoR determination based on the detection of the maximum variance of reconstructed slices failed, so we develop a new CoR search method based in the detection of the variance sharpest local maximum. We show the capabilities of the system to give quantitative information of different types of hydrogels that may be useful in its characterization.The authors thank to Tekes, Finnish Cultural Foundation, CIMO, Jane and Aatos Erkko Foundation and EXTREMA COST Action MP1207 for supporting this work