Tissue Optics and Photonics: Biological Tissue Structures

Abstract

Abstract. This is the first section of the review--tutorial paper describing fundamentals of tissue optics and photonics mostly devoted to biological tissue structures and their specificity related to light interactions at its propagation in tissues. The next sections of the paper will describe light--tissue interactions caused by tissue dispersion, scattering, and absorption properties, including light reflection and refraction, absorption, elastic quasi--elastic and inelastic scattering. The major tissue absorbers and types of elastic scattering, including Rayleigh and Mie scattering, will be presented. © 2015 Samara State Aerospace University (SSAU).Keywords: biophotonics; tissue optics; tissue structures. C. J. Gemert (eds.), Academic, NY (1992 Digest 11, 191-199 (1990 Hodson, "Transparency of the bovine corneal stroma at physiological hydration and its dependence on concentration of the ambient anion," J. Physiol. 543, 633-642 (2002). 85. K. M. Meek, S. Dennis, and S. Khan, "Changes in the refractive index of the stroma and its extrafibrillar matrix when the cornea swells," Biophys. J. 85, 2205-2212 (2003). 86. H. Schaefer, and T. E. Redelmeier, Skin Barrier: Principles of Percutaneous Absorption, Karger, Basel (1996). (7), 375-416 (2014). 104. E. I. Galanzha, M. S. Kokoska, E. V. Shashkov, J.-W. Kim, V. V. Tuchin, and V. P. Zharov, "In vivo fiber photoacoustic detection and photothermal purging of metastasis targeted by nanoparticles in sentinel lymph nodes at single cell level," J.

Tissue Optics and Photonics: Light-Tissue Interaction

“…A biological tissue is a dielectric medium whose average refractive index is higher than that of air [1][2][3][4][5]. Thus at interaction with tissue surface the light radiation is able to undertake partial reflection at the tissue/air interface (Fresnel reflection), while the remaining part penetrates the tissue (see Fig.…”

“…Thus they could be applied only locally for a limited number of tissues such as healthy eye cornea, lens and vitreous body (see Fig. 2.6) [1]. However, the major types of tissues are optically inhomogeneous (turbid) and absorptive multilayered media with rough interfaces.…”

“…The NIR absorption spectrum of myoglobin is essentially identical to that of hemoglobin, so that it is not possible to monitor it independently without resorting to a supplementary technique. [1]. In view of the great diversity and structural complexity of tissues, the development of an adequate optical model accounting for the scattering and absorption of light is often the most complex step of a study [2][3][4][5][10][11][12][13][14][15][16][17][18][19][20][21].…”

“…For example, this is a case for healthy transparent front human eye tissues, such as cornea, eye lens and vitreous body (see Fig. 2.6) [1], or for a tissue slice which is sufficiently thin that single scattering approximation accurately estimates the reflection and transmission of the slab. In contrast, in many real situations, especially in in vivo studies of skin, breast, brain and etc., a multiple scattering -a scattering process, in which on average each photon undertakes many scattering events, is more likely [2][3][4][5].…”

“…(1.5)] [1] with the beam axis normal to the object plane and beam waist apart at a distance z from the object plane (see Fig. 3.23), the beam spot radius w b and radius of wavefront curvature ρ b in the object plane are determined by the following expressions [55]:…”