Non-invasive optical monitoring of human lungs: Monte Carlo modeling of photon migration in Visible Chinese Human and an experimental test on a human

The human lung was quantified and visualized by photon transport in this paper. A Monte Carlo (MC) simulation of voxelized media was used with the visible Chinese human (VCH). This study theoretically explored the feasibility of non-invasive optical detection of pulmonary hemodynamics, and investigated the optimal location of the light source in the lung photon migration and optimized the source-detector distance. The light fluence intensity showed that the photon penetration depth was 6-8.4 mm in the human lung. The optimal distance from the light source to the detector was 2.7-2.9 cm, but the optimal distance of the superior lobe of right lung was 3.3-3.5 cm. We then conducted experiments on diffuse light reflectance using NIRS on 14 volunteers. These measurements agree well with the simulation results. All the results demonstrated the great potential of non-invasive monitoring of pulmonary hemodynamics and contribute to the study of human lungs in the biomedical optics community.