Analysis of light propagation in neonatal head model by finite difference method

The light propagation in a simple layered ellipse model and more complex neonatal head model are calculated by the finite-difference method. The finite-difference method has advantage of simple algorithm and fast calculation time however has been successful under restricted condition for a heterogeneous medium. The light propagation in the both models is predicted by Monte Carlo simulation to validate the results of the finite-difference method. The detected intensity and partial optical path length calculated by the finite-difference method agree with those by Monte Carlo simulation. The boundary of the grey and white matter in the neonatal head model is more complex than the simple ellipse model. However, the tendency of spatial sensitivity profiles in the neonatal head model is scarcely affected by the effect of heterogeneity of the brain tissue.