Methodology development and evaluation of optical properties characterisation of small size tissue samples

Yijing Xie; Jonathan Shapey; Eli Nabavi; Peichao Li; Anisha Bahl; Michael Ebner; Tom Vercauteren

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arXiv · 2107.04909

Methodology development and evaluation of optical properties characterisation of small size tissue samples

Yijing Xie·Jonathan Shapey·Eli Nabavi·Peichao Li·Anisha Bahl·Michael Ebner·Tom Vercauteren

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Abstract

Integrating sphere (IS) techniques combined with an inverse adding doubling (IAD) algorithm have been widely used for determination of optical properties of ex vivo tissues. Semi-infinite samples are required in such cases. The aim of this study is to develop a methodology for calculating the optical absorption and reduced scattering of biological tissues of small size from IS measurements at 400-1800 nm. We propose a two-stage IAD algorithm to mitigate profound cross-talk effects in the estimation of the reduced scattering in the case of very high absorption. We developed a small sample adaptor kit to allow IS measurements of samples with small sizes using a commercial spectrophotometer. Results showed that: The two-stage IAD substantially eliminated the cross-talks in the reduced scattering spectra, thus rectifying absorption accordingly; and the small sized sample measurements led to systematically overestimated absorption values while the spectrum shape well preserved as compared to the normal port size measurements.

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Yijing Xie, Jonathan Shapey, Eli Nabavi, Peichao Li, Anisha Bahl, Michael Ebner, Tom Vercauteren. 2021-12-15. Methodology development and evaluation of optical properties characterisation of small size tissue samples. https://arxiv.org/abs/2107.04909

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