Kirillin Mikhail, Khilov Aleksandr, Kurakina Daria, Orlova Anna, Perekatova Valeriya, Shishkova Veronika, Malygina Alfia, Mironycheva Anna, Shlivko Irena, Gamayunov Sergey, Turchin Ilya, Sergeeva Ekaterina
Institute of Applied Physics RAS, 46 Ulyanov St., 603950 Nizhny Novgorod, Russia.
Institute of Information Technology, Mathematics and Mechanics, Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Avenue, 603022 Nizhny Novgorod, Russia.
Cancers (Basel). 2021 Nov 19;13(22):5807. doi: 10.3390/cancers13225807.
Fluorescence imaging modalities are currently a routine tool for the assessment of marker distribution within biological tissues, including monitoring of fluorescent photosensitizers (PSs) in photodynamic therapy (PDT). Conventional fluorescence imaging techniques provide en-face two-dimensional images, while depth-resolved techniques require complicated tomographic modalities. In this paper, we report on a cost-effective approach for the estimation of fluorophore localization depth based on dual-wavelength probing. Owing to significant difference in optical properties of superficial biotissues for red and blue ranges of optical spectra, simultaneous detection of fluorescence excited at different wavelengths provides complementary information from different measurement volumes. Here, we report analytical and numerical models of the dual-wavelength fluorescence imaging of PS-containing biotissues considering topical and intravenous PS administration, and demonstrate the feasibility of this approach for evaluation of the PS localization depth based on the fluorescence signal ratio. The results of analytical and numerical simulations, as well as phantom experiments, were translated to the in vivo imaging to interpret experimental observations in animal experiments, human volunteers, and clinical studies. The proposed approach allowed us to estimate typical accumulation depths of PS localization which are consistent with the morphologically expected values for both topical PS administration and intravenous injection.
荧光成像方式目前是评估生物组织内标记物分布的常规工具，包括在光动力疗法（PDT）中监测荧光光敏剂（PSs）。传统的荧光成像技术提供二维表面图像，而深度分辨技术则需要复杂的断层成像方式。在本文中，我们报告了一种基于双波长探测估计荧光团定位深度的经济有效方法。由于浅表生物组织在光谱的红色和蓝色范围内光学特性存在显著差异，同时检测不同波长激发的荧光可从不同测量体积提供互补信息。在此，我们报告了考虑局部和静脉注射PS给药的含PS生物组织双波长荧光成像的分析和数值模型，并证明了基于荧光信号比评估PS定位深度这种方法的可行性。分析和数值模拟结果以及模型实验结果被转化为体内成像，以解释动物实验、人体志愿者和临床研究中的实验观察结果。所提出的方法使我们能够估计PS定位的典型积累深度，这与局部PS给药及静脉注射在形态学上预期的值一致。
