Improving the characterization of ex vivo human brain optical properties using high numerical aperture optical coherence tomography by spatially constraining the confocal parameters.
Improving the characterization of ex vivo human brain optical properties using high numerical aperture optical coherence tomography by spatially constraining the confocal parameters.
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DOI：
10.1117/1.nph.7.4.045005
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发表时间：
2020-10
期刊：
影响因子：
5.3
通讯作者：
Boas DA
中科院分区：
文献类型：
--
作者：
Yang J;Chen IA;Chang S;Tang J;Lee B;Kılıç K;Sunil S;Wang H;Varadarajan D;Magnain C;Chen SC;Costantini I;Pavone F;Fischl B;Boas DA
重要性：生物样品的光学性质提供了关于组织的结构特征和由病理条件引起的任何变化的信息。光学相干断层扫描（OCT）已被证明是能够提取组织的光学特性，使用一个模型，该模型结合了由于组织散射的指数衰减和轴向点扩散函数，从共焦性质的检测系统，特别是更高的数值孔径（NA）的测量。在估计的光学特性的弱点是组织散射和共焦参数之间的参数间串扰定义的瑞利范围和焦点深度。目的：在这项研究中，我们开发了一种系统的方法，以提高光学特性的表征与高NA OCT。方法：我们开发了一种方法，空间参数化的共焦参数在先前建立的模型估计的光学特性，从深度剖面的高NA OCT。结果：提出的参数化模型首先在一组内隐体模型上进行评估，然后使用低NA目标进行验证，其中交叉-来自共焦参数的干扰是可以忽略的。然后，我们利用我们的空间参数化模型来表征由使用简单的浸渍剂2，2 '-硫代二乙醇醛的组织折射率匹配过程引入的光学性质变化。结论：我们的方法通过减少非线性拟合模型中的自由度来提高参数估计的置信度。
Significance: The optical properties of biological samples provide information about the structural characteristics of the tissue and any changes arising from pathological conditions. Optical coherence tomography (OCT) has proven to be capable of extracting tissue’s optical properties using a model that combines the exponential decay due to tissue scattering and the axial point spread function that arises from the confocal nature of the detection system, particularly for higher numerical aperture (NA) measurements. A weakness in estimating the optical properties is the inter-parameter cross-talk between tissue scattering and the confocal parameters defined by the Rayleigh range and the focus depth. Aim: In this study, we develop a systematic method to improve the characterization of optical properties with high-NA OCT. Approach: We developed a method that spatially parameterizes the confocal parameters in a previously established model for estimating the optical properties from the depth profiles of high-NA OCT. Results: The proposed parametrization model was first evaluated on a set of intralipid phantoms and then validated using a low-NA objective in which cross-talk from the confocal parameters is negligible. We then utilize our spatially parameterized model to characterize optical property changes introduced by a tissue index matching process using a simple immersion agent, 2,2’-thiodiethonal. Conclusions: Our approach improves the confidence of parameter estimation by reducing the degrees of freedom in the non-linear fitting model.