无损光学法测量人胃粘膜/粘膜下层组织的光衰减特性

Noninvasive Measurements for Optical Attenuation Characteristics of Human Stomach Mucosa/Submucosa Tissues Using Optical Methods

研究了人正常胃粘膜及粘膜下层组织对640 nm,690 nm,740 nm,790 nm,840 nm和890 nm波长的钛宝石激光的光衰减特性以及光学穿透深度,实验采用激光斜入射式空间分辨反射光和CCD探测器以及非线性拟合确定组织光学特性。结果表明:人正常胃粘膜及粘膜下层组织对六个波长的激光的有效衰减系数和光学穿透深度都是随着激光波长的变化而变化的。其有效衰减系数的最大值在640 nm,其值为1.12 mm-1,最小值在790 nm,其值为0.901 mm-1,最大差异在790 nm和890 nm之间,其值为19.9%,最小差异在690 nm和740nm之间,其值为2.83%。其光学穿透深度的最大值在790 nm,其值为1.11 mm,最小值在640 nm,其值为0.890 mm,最大差异在640 nm和790 nm之间,其值为24.7%,最小差异在690 nm和740 nm之间,其值为2.97%。

The purpose of the study is to determine the optical attenuation characteristics and the optical penetration depths for normal human stomach mucosa/submucosa tissues in vitro at 640, 690, 740, 790, 840 and 890 nm wavelength of laser. The measurements were performed using a CCD detector, and the optical properties were assessed from the measurements using an obliquely incident laser beam, and spatially resolved reflectance, and nonlinear fitting of diffusion equation. The results of measurements showed that the optical attenuation characteristics and the optical penetration depths for the tissue samples at six different laser wavelengths vary with a change of laser wavelength. The maximum optical attenuation characteristic for tissue samples is 1.12 mm^-1 at 640 nm, and the minimum optical attenuation characteristic is 0. 901 mm^-1 at 790 nm, and the maximum difference in the optical attenuation characteristics is 19.9 % between 790 nm and 890 nm, and the minimum difference is 2.83 % between 690 nm and 740 nm. The maximum optical penetration depth for tissue samples is 1.11 mm at 790 nm, and the minimum optical penetration depth is 0. 890 mm at 640 nm, and the maximum difference in the optical penetration depths is 24.7 % between 640 nm and 790 nm, and the minimum difference is 2.97 % between 690 nm and 740 nm.