Spectral characterization of transparency mechanisms in cardiac
muscle
M. Pinheiro1, M. Carvalho1'2, V. Tuchin3'4'5, L. Oliveira1'6*
1-Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Campus da FEUP,
Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
2- Department of Electrical and Computer Engineering, Faculty of Engineering of Porto University (FEUP),
Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
3- Institute of Physics and Science Medical Center, Saratov State University, 83 Astrakhanskaya str., Saratov
410012, Russian Federation
4- Laboratory of Laser Diagnostics of Technical and Living Systems, Institute ofPrecision Mechanics and
Control of the FRC "Saratov Scientific Centre of the Russian Academy of Sciences", 24 Rabochaya, Saratov 410028, Russian Federation
5- Laboratory of Laser Molecular Imaging and Machine Learning, Tomsk State University, Tomsk 634050,
Russian Federation
6- Physics Department, School of Engineering, Polytechnic of Porto, Rua Dr. Antonio Bernardino de Almeida
n° 431, 4249-015 Porto, Portugal
The evaluation of the diffusion properties of drugs, chemicals and other agents in biological tissues has a great interest in various fields, such as diagnostic and treatment applications, pharmacology, and cosmetology. These properties are also fundamental for the characterization of the mechanisms that lead to transient transparency effects in tissues that are induced by optical clearing agents (OCAs) and therefore are of great importance for laser treatments of heart pathologies. Different optical methods have been used to evaluate the diffusion properties of various OCAs in different tissues [1]. With the purpose of characterizing the two fundamental optical clearing mechanisms in cardiac muscle, kinetic thickness and spectroscopy measurements were performed from tissue samples to evaluate the diffusion times and the diffusion coefficients of water and glycerol in this tissue, as well as the efficiency of transport of laser beams through cardiac muscle.
[1] V. Tuchin, D. Zhu, E. Genina, Handbook of Tissue Optical Clearing (CRC Press), (2022).