title: Experimental and theoretical evaluation of a fiber-optic approach for optical property measurement in layered epithelial tissue.
abstract: Improvements in measurement of epithelial tissue optical properties (OPs) in the ultraviolet and visible (UV-Vis) may lead to enhanced understanding of optical techniques for neoplasia detection. In this study, we investigated an approach based on fiber-optic measurement of reflectance to determine absorption and reduced scattering coefficients (μ(a) and μ(s)') in two-layer turbid media. Neural network inverse models were trained on simulation data for a wide variety of OP combinations (μ(a) = 1-22.5, μ(s)' = 5-42.5 cm(-1)). Experimental measurements of phantoms with top-layer thicknesses (D) ranging from 0.22 to 0.66 mm were performed at three UV-Vis wavelengths. OP estimation accuracy was calculated and compared to theoretical results. Mean prediction errors were strongly correlated with D and ranged widely, from 1.5 to 12.1 cm(-1). Theoretical analyses indicated the potential for improving accuracy with alternate probe geometries. Although numerous challenges remain, this initial experimental study of an unconstrained approach for fiber-optic-based OP determination in two-layer epithelial tissue indicates the potential to provide useful measurements.
authors.affiliation: Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, Maryland 20993, USA. quanzeng.wang@fda.hhs.gov
authors.forename: Quanzeng
authors.initials: Q
authors.lastname: Wang
authors.forename: Karthik
authors.initials: K
authors.lastname: Shastri
authors.forename: T Joshua
authors.initials: TJ
authors.lastname: Pfefer
mesh_terms: D004848:Epithelium / Q000033:anatomy & histology*; D005336:Fiber Optic Technology / Q000379:methods* / Q000639:trends*; D008962:Models, Theoretical; D009010:Monte Carlo Method; D055620:Optical Phenomena; D055095:Optics and Photonics; D019047:Phantoms, Imaging