Modeling of light propagation in the human neck for diagnoses of thyroid cancers by diffuse optical tomography
Modeling of light propagation in the human neck for diagnoses of thyroid cancers by diffuse optical tomography
复制标题
通过漫射光学断层扫描对人颈部光传播进行建模以诊断甲状腺癌
DOI：
10.1002/cnm.2826
复制
发表时间：
2017
影响因子：
2.1
通讯作者：
Hoshi Yoko
中科院分区：
文献类型：
--
作者：
Fujii Hiroyuki;Yamada Yukio;Kobayashi Kazumichi;Watanabe Masao;Hoshi Yoko
使用波长范围为700至1000 nm的近红外光的漫射光学断层扫描有可能实现甲状腺癌的非侵入性诊断;其中一些甲状腺癌很难通过常规方法（如超声断层扫描）检测。漫射光学断层成像需要基于颈部中光传播的物理精确模型，因为它通过逆分析来重建人体颈部中光学特性的断层成像图像。我们的目的是使用2D时变辐射传输方程研究三个因素对光在颈部传播的影响：（1）气管的存在，（2）气管-组织界面处的折射率失配，以及（3）除气管外的颈部器官（脊柱、脊髓和血管）的影响。气管-组织界面处的反射和折射对气管和颈部表面前部之间区域的光强度有显著影响。除了气管以外的器官对在颈部表面前部测量的光强度几乎没有影响，尽管这些器官局部地影响光强度。这些结果表明，有必要对气管-组织界面处的折射率失配进行建模，并且当源和探测器远离大血管时，可以将其他颈部器官简单地建模为均匀介质。
Diffuse optical tomography using near‐infrared light in a wavelength range from 700 to 1000 nm has the potential to enable non‐invasive diagnoses of thyroid cancers; some of which are difficult to detect by conventional methods such as ultrasound tomography. Diffuse optical tomography needs to be based on a physically accurate model of light propagation in the neck, because it reconstructs tomographic images of the optical properties in the human neck by inverse analysis. Our objective here was to investigate the effects of three factors on light propagation in the neck using the 2D time‐dependent radiative transfer equation: (1) the presence of the trachea, (2) the refractive‐index mismatch at the trachea‐tissue interface, and (3) the effect of neck organs other than the trachea (spine, spinal cord, and blood vessels). There was a significant influence of reflection and refraction at the trachea‐tissue interface on the light intensities in the region between the trachea and the front of the neck surface. Organs other than the trachea showed little effect on the light intensities measured at the front of the neck surface although these organs affected the light intensities locally. These results indicated the necessity of modeling the refractive‐index mismatch at the trachea‐tissue interface and the possibility of modeling other neck organs simply as a homogeneous medium when the source and detectors were far from large blood vessels.