CC BY
14B-I-6
Optical imaging for development and advancement of photodynamic therapy protocols
M. Kirillin1, D. Kurakina1, A. Khilov1, A. Orlova1, E. Sergeeva1, M. Shakhova2, A. Mironycheva3, A. Malygina3,I. Shlivko3, N. Orlinskaya4
institute of Applied Physics RAS, Laboratory of Biophotonics, Nizhny Novgorod, Russian Federation
2Privolzhsky Research Medical University, ENT Department, Nizhny Novgorod, Russian Federation
3Privolzhsky Research Medical University, Skin Diseases Department, Nizhny Novgorod, Russian Federation
4Privolzhsky Research Medical University, Pathomorphology Department, Nizhny Novgorod, Russian Federation
Photodynamic therapy (PDT) is a modern treatment technique efficient against a number of tumor and non-tumor pathologies. This technique is based on photoactivation of a photosensitizer (PS) accumulated in the treated area prior to the procedure. Target delivery of PS to the treatment area in combination with proper illumination configuration provides high treatment specificity with low impact to surrounding healthy tissues. Specific optical properties of various PSs provide additional opportunities in configuring PDT protocols. Current paper reports on studies with chlorine-based PSs exhibiting pronounced absorption maxima in the blue and red spectral ranges. Due to spectral dependence of biotissue optical properties employment of different light wavelengths efficiently absorbed by a PS allows to select between superficial and deep action. Development of novel efficient PDT protocols requires for accurate control of a PDT procedure. Optical imaging techniques have high potential in monitoring of a PDT procedure: fluorescence imaging allows to monitor PS accumulation and photobleaching in the course of irradiation, while optical coherence tomography (OCT) with angiographic modality provides structural and functional information about biotissue.
In this paper we report on application of optical imaging techniques for monitoring of PDT performance in both experimental animal studies and clinical practice. The animal study aimed at comparative analysis of anti-tumor PDT protocols with chlorine-based PS employing irradiation with red and blue light and their combination on model CT-26 tumors in mice. The outcomes were verified by a histological inspection. The clinical part of the work reports on development of PDT protocols assisted by optical imaging modalities for treatment of actinic keratosis and basal cell carcinoma. Non-invasive intra-procedural temperature control is proposed as an additional tool for treatment tactics personalization.
The study is supported by Russian Science Foundation (project 17-15-01264).
