Strategies for absolute calibration of near infrared tomographic tissue imaging.
Strategies for absolute calibration of near infrared tomographic tissue imaging.
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DOI：
10.1007/978-1-4615-0075-9_9
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发表时间：
2003
影响因子：
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通讯作者：
T. O. McBride;B. Pogue;U. Osterberg;K. Paulsen
中科院分区：
文献类型：
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作者：
T. O. McBride;B. Pogue;U. Osterberg;K. Paulsen
组织的定量近红外 (NIR) 成像需要使用基于扩散模型的重建算法，该算法通过将光的透射测量与预测扩散方程解相匹配来求解组织体积的吸收和散射系数。当对真实系统使用基于模型的方法时，成像系统会出现校准问题以及其他实际考虑因素。例如，必须去除数据采集硬件和源/检测器光纤中的系统噪声，以防止重建图像中出现虚假结果。 NIR 漫射断层扫描成像系统的实际考虑因素包括：(1) 使用同质体模进行校准，(2) 使用同质拟合算法来获得异质介质图像重建的初始光学特性估计，以及 (3) 对数据采集期间源强度和初始相位偏移的波动进行校正。描述了这些依赖于精确齐次拟合算法的实际考虑因素。他们展示了一种原型成像系统，该系统能够在没有先验信息的情况下定量重建高度散射介质内血红蛋白浓度的异质图像。
Quantitative near infrared (NIR) imaging of tissue requires the use of a diffusion model-based reconstruction algorithm, which solves for the absorption and scattering coefficients of a tissue volume by matching transmission measurements of light to the predictive diffusion equation solution. Calibration problems as well as other practical considerations arise for an imaging system when using a model-based method for a real system. For example, systematic noise in the data acquisition hardware and source/detector fibers must be removed to prevent spurious results in the reconstructed image. Practical considerations for a NIR diffuse tomographic imaging system include: (1) calibration with a homogeneous phantom, (2) use of a homogeneous fitting algorithm to arrive at an initial optical property estimate for image reconstruction of a heterogeneous medium, and (3) correction for fluctuations in source strength and initial phase offset during data acquisition. These practical considerations, which rely on an accurate homogeneous fitting algorithm are described. They have allowed demonstration of a prototype imaging system that has the ability to quantitatively reconstruct heterogeneous images of hemoglobin concentrations within a highly scattering medium with noa prioriinformation.