Photobleaching Characteristics during the Photodynamic Therapy

Based on the distribution of photons in tumor during photodynamic therapy,effection of photobleaching caused by optical properties of tumor and the distribution of photons is researched.It showed that effection of photobleaching is inversed to absorption coefficient and scattering coefficient.And effective depth of photobleaching is 4.5 mm, the maximum depth of photobleaching is 33 mm.The results,which has important reference value for clinic to design an optimal scheme for photodynamic therapy,showed that it is effective for studying photobleaching characteristics.