Kim Oleg, McMurdy John, Jay Gregory, Lines Collin, Crawford Gregory, Alber Mark
Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, Notre Dame, 46556, Indiana.
Division of Engineering, Brown University, Providence, 02912, Rhode Island.
Physiol Rep. 2014 Jan 8;2(1):e00192. doi: 10.1002/phy2.192. eCollection 2014 Jan 1.
A combination of stochastic photon propagation model in a multilayered human eyelid tissue and reflectance spectroscopy was used to study palpebral conjunctiva spectral reflectance for hemoglobin (Hgb) determination. The developed model is the first biologically relevant model of eyelid tissue, which was shown to provide very good approximation to the measured spectra. Tissue optical parameters were defined using previous histological and microscopy studies of a human eyelid. After calibration of the model parameters the responses of reflectance spectra to Hgb level and blood oxygenation variations were calculated. The stimulated reflectance spectra in adults with normal and low Hgb levels agreed well with experimental data for Hgb concentrations from 8.1 to 16.7 g/dL. The extracted Hgb levels were compared with in vitro Hgb measurements. The root mean square error of cross-validation was 1.64 g/dL. The method was shown to provide 86% sensitivity estimates for clinically diagnosed anemia cases. A combination of the model with spectroscopy measurements provides a new tool for noninvasive study of human conjunctiva to aid in diagnosing blood disorders such as anemia.
结合多层人体眼睑组织中的随机光子传播模型和反射光谱技术，用于研究睑结膜光谱反射率以测定血红蛋白（Hgb）。所开发的模型是首个与眼睑组织生物学相关的模型，已证明其能很好地逼近实测光谱。利用先前对人体眼睑的组织学和显微镜研究来定义组织光学参数。在校准模型参数后，计算反射光谱对Hgb水平和血液氧合变化的响应。正常和低Hgb水平成年人的模拟反射光谱与Hgb浓度在8.1至16.7 g/dL范围内的实验数据吻合良好。将提取的Hgb水平与体外Hgb测量值进行比较。交叉验证的均方根误差为1.64 g/dL。该方法对临床诊断的贫血病例的敏感性估计为86%。该模型与光谱测量相结合，为人体结膜的无创研究提供了一种新工具，有助于诊断贫血等血液疾病。
