Hybrid Spectroscopic Topography for Functional Imaging of Oxygenation

这项研究的目的是开发用于生物医学的混合光学地形图，它可以同时测量血液的流动、浓度和氧合，以及皮肤组织中血层的深度和厚度。研究了血液的光吸收特性，选择了最佳波长为780 nm和830 nm，其中830 nm的灵敏度更高。基于修正的Lambert-Beer定律，提出了一种利用散斑图像的时间积分吸光度及其多元回归分析来估计包括光程长度在内的血药浓度的方法。研制并优化了一套散斑图像采集装置和图像处理程序，并利用基于琼脂溶液的皮肤组织模型进行了实验。这一结果证实了挖掘相对变异的有用性。基于高斯点扩散函数的反褶积处理，实现了地形图像的锐化。利用我们自己的等色散波长方法，编制了分析算法和程序，在一定条件下估算出血红蛋白浓度(摩尔/升)和氧合(%)，以及深度和厚度。最终将该方法与前述技术相结合，开发了一套测量深度、厚度以及血流量、浓度和血氧饱和度的系统。该系统被应用于皮肤组织模特体和人类志愿者的实验，以验证其有效性，包括分辨率。

The purpose of this study is to develop hybrid optical topography for bio-medicine, which provides us simultaneous measurements on the flow, concentration and oxygenation of blood together with the depth and thickness of the blood layer in skin tissue.1. Optical absorbance properties of blood were investigated to choose the optimum wavelength of 780 and 830 nm, the latter of which was found to better for sensitivity.2. A new method was proposed for estimation of the blood concentration including optical path length using the time-integrated absorbance of speckle images and their multiple regression analysis based on the modified Lambert-Beer law.3. An apparatus for speckle image acquisition and image processing program were developed and optimized, and used to make experiments using skin tissue phantoms based on the agar solution. The result confirmed the usefulness for dig the relative variation.4. Deconvolution processing was developed on the basis of Gaussian point spread function to sharpen topographic images.5. Analyzing algorithm and program were developed by using our own method with isosbestic wavelengths to estimate the hemoglobin concentration (mol/liter) and oxygenation (%), together with the depth and thickness under certain conditions.6. The proposed method was finally unified with the preceding technique to develop a system for measuring the depth and thickness as well as the blood flow and concentration and oxygen saturation. The system was applied to experiments on skin tissue phantoms and human volunteers to verify the usefulness including resolution.