Characterization of thin poly(dimethylsiloxane)-based tissue-simulating phantoms with tunable reduced scattering and absorption coefficients at visible and near-infrared wavelengths

Abstract

Abstract. Optical phantoms are used in the development of various imaging systems. For certain applications, the development of thin phantoms that simulate the physical size and optical properties of tissue is important. Here, we demonstrate a method for producing thin phantom layers with tunable optical properties using poly (dimethylsiloxane) (PDMS) as a substrate material. The thickness of each layer (between 115 and 880 μm) was controlled using a spin coater. The reduced scattering and absorption coefficients were controlled using titanium dioxide and alcohol-soluble nigrosin, respectively. These optical coefficients were quantified at six discrete wavelengths (591, 631, 659, 691, 731, and 851 nm) at varying concentrations of titanium dioxide and nigrosin using spatial frequency domain imaging. From the presented data, we provide lookup tables to determine the appropriate concentrations of scattering and absorbing agents to be used in the design of PDMS-based phantoms with specific optical coefficients. In addition, heterogeneous phantoms mimicking the layered features of certain tissue types may be fabricated from multiple stacked layers, each with custom optical properties. These thin, tunable PDMS optical phantoms can simulate many tissue types and have broad imaging calibration applications in endoscopy, diffuse optical spectroscopic imaging, and optical coherence tomography, etc. © The Authors.Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Design and validation of a diffuse reflectance and spectroscopic microendoscope with poly(dimethylsiloxane)-based phantoms

“…21 For these experiments, the absorption and reduced scattering coefficients of phantoms can be directly quantified using methods such as spatial frequency domain imaging. 18, 22 …”

“…All components were mixed in a previously described method. 18 Three 1.5 centimeter thick monolayer phantom layers were constructed with a constant concentration of 1% w/v nigrosin/EtOH (5.0 μL/g PDMS) and a varying concentration of TiO 2 (4.0, 8.0, and 12.0 mg/g PDMS). Two more 1.5 centimeter thick monolayer phantom layers were constructed so that three total phantoms had a constant concentration of TiO 2 (8.0 mg/g PDMS) and a varying concentration of 1% w/v nigrosin/EtOH (2.5, 5.0, and 10.0 μL/g PDMS).…”

Towards monitoring dysplastic progression in the oral cavity using a hybrid fiber-bundle imaging and spectroscopy probe

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Spatially resolved diffuse reflectance spectroscopy of two-layer turbid media by densely packed multi-pixel photodiode reflectance probe

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