Experimental investigation and simultaneous modeling of the effect of methylene blue addition to cancer tumors in photodynamic therapy by digital holography

Background: Although many types of cancers can be treated with surgery, alternatives such as photodynamic therapy with simultaneous use of photosensitive materials and illumination can also be used. Knowing the dose of absorbed energy from the light beam in the photo-sensitized tumors and tissues has an important role in designing the optimal irradiation method with the aim of investigating the amount of received damage to the healthy and tumor tissues.Methods: In this study, the effect of the presence of methylene blue sensitizer on the amount of dose received in tissue-equivalent material has been investigated experimentally by Mach-Zehnder interferometry and digital holography. The Monte Carlo method and the ValoMC code have been used to confirm the results obtained in the experimental phase.Results: The results indicate the positive role of methylene blue in increasing the absorbed dose of tumor -equivalent material. The amount of light dose increase and the two-dimensional profile of the dose absorbed in tissue and tumor equivalent materials have been measured by digital holography.Conclusions: The method presented in this work can be used in treatment design and real time measuring of the spatially resolved distribution of the absorbed dose in the tissues containing tumors.