Simulation Study for the Penetration Depth of Red and Near Infrared Light in Muscle Tissue

Light dosimetry is an important procedure in photodynamic therapy for tumor kill without harming the healthy tissue. For correct dosimetry, the penetration depth of the light into the tissue is one of the important parameters. In this study, fluence and penetration depth for the wavelengths of 650 nm and 830 nm in the muscle tissue have been investigated using Monte Carlo simulations. It is found that the decrease in the fluence of the 650 nm with the increase in depth is sharper than that of 830 nm. In addition, the penetration depth of muscle tissue for the wavelengths of 650 nm and 830 nm are found to be 1.57 and 3.23, respectively, which are reasonably agree with the experimental ones (1.47 and 3.72) reported in the literature.