Contactless diagnostics of biophysical parameters of skin and blood on the basis of approximating functions for radiation fluxes scattered by skin

Method for Estimating Bilirubin Isomerization Efficiency in Phototherapy to Treat Neonatal Jaundice

“…The tissue concentration of bilirubin can be determined by noninvasive methods by measuring the spectral or the spectral and spatial characteristics of the diffuse refl ection by the tissue [14-16, 21, 22]. The measurements can be made based on both fi ber-optic technology [14][15][16] and contactless measurement systems [21,22]. Analytical solutions of the corresponding forward and inverse problems, proposed in [14,16,21,22], allow us to process the measurement data in real time and with high accuracy.…”

“…In this case, the collection aperture for photons backscattered by the medium corresponds to the entire area of the medium covered by the entrance port of the integrating sphere. We proposed an analytical model for the diffuse refl ection coeffi cient of skin corresponding to such an experimental geometry in [22]. This model allows us to calculate the diffuse refl ection coeffi cient of skin as a function of the thickness of the epidermis and the optical parameters (absorption coeffi cient and scattering transport coeffi cient) of the epidermis and dermis.…”

“…The measurements can be made based on both fi ber-optic technology [14][15][16] and contactless measurement systems [21,22]. Analytical solutions of the corresponding forward and inverse problems, proposed in [14,16,21,22], allow us to process the measurement data in real time and with high accuracy. Taking into account the similarity of the absorption spectra for ZZ-bilirubin and ZE-bilirubin [19], the total bilirubin concentration, determined based on the methods indicated above, will correspond to the total concentration of bilirubin photoisomers in tissue (C TB ).…”

“…Let the change in the ZZ-bilirubin concentration in the skin tissues, due to its production in blood, during this time period be ΔC ZZ . The value of ΔC ZZ can be determined based on noninvasive measurements of the total bilirubin concentration in the skin of the patient before phototherapy begins [14][15][16]22]. Then the illumination of the skin of the patient during phototherapy should satisfy the obvious condition:…”

“…For specifi ed parameters of the medium modeling skin tissue, the optical characteristics of the medium, taking into account the above comments, are calculated using the formulas [14][15][16]22]:…”