CC BY
7B-I-24
Lasers for skin diagnostics - chromophore mapping and photon path length estimation
J. Spigulis1
institute of Atomic Physics and Spectroscopy, Biophotonics Laboratory, Riga, Latvia
Recent developments in two laser technologies for in-vivo skin diagnostics will be discussed -multi-laser illumination for snapshot mapping of the main skin chromophores [1], and diffuse reflectance of picosecond laser pulses for determination of photon path lengths in skin structures [2]. A new prototype device enabling simultaneous uniform illumination of skin area by five laser wavelengths (405 nm, 445 nm, 520 nm, 635 nm, 850 nm) is under development and will undergo clinical validation. 405 nm laser line is used for skin autofluorescence excitation, while the spectral line images obtained at illumination by the other four laser wavelengths are exploited for distribution mapping of skin melanin, oxy-hemoglobin, deoxy-hemoglobin and bilirubin. Shape analysis of skin-remitted picosecond laser pulses in the spectral range 520-800 nm provided opportunity to experimentally determine the distributions of photon path lengths in skin at various input-output distances. Knowledge of such distributions helps to improve accuracy and reliability of the skin chromophore maps.
References
[1] J. Spigulis, I. Oshina, A. Berzina, A. Bykov, "Smartphone snapshot mapping of skin chromophores under triple-wavelength laser illumination", J.Biomed.Opt., 22(9), 091508 (2017).
[2] M. Osis, V .Lukinsone, J. Latvels, I. Kuzmina, U. Rubins, J. Spigulis, "Skin remittance kinetics at the spectral range 550-790 nm", Quant.Electr., 49(1), 2-5 (2019).
