A new mathematical approach to the diffusion approximation theory for selective photothermolysis modeling and its implication in laser treatment of port‐wine stains

To study laser treatments of PWS with the diffusion approximation, FEM is an effective method to calculate the coagulation patterns within specific blood vessels. To improve coagulation efficacy at 585 and 595-nm wavelengths, the radiant exposure should be increased without increasing the irradiance.