Approaches to estimate the mean path length of photons for tissue oxygenation measurement

The mean path length (MPL) of photons is a key parameter for calculation of blood oxygenation using near-infrared light. With Monte Carlo simulation of photons in the leg tissue, this study compares four approaches to estimate MPL. The results demonstrate that the MPL could be accurately estimated by a combination of the direct average and weighted average over the detected photon path lengths.