Significance: Terahertz wave is a potential tool for biological tissues due to its noninvasiveness and high sensitivity to water. Attenuated total reflection (ATR) with the characteristics of high sensitivity and nondestruction has been applied for THz imaging. Aim: We aim to develop an imaging methodology to facilitate practical application of THz ATR imaging. Approach: We have demonstrated a horizontally scanning THz continuous wave ATR imaging system. The effective imaging area was as large as the prism imaging surface by optimizing the ATR prism, and the influence of secondary reflection can be well avoided. By taking the image resolution and stability of this system into consideration, the incident angle α to the prism bottom was chosen to be 30 deg. Results: The image resolution of this system can be up to 400 and 450    μ m in horizontal and vertical directions, respectively. Furthermore, U87-glioma regions of mice brain tissues with different sizes and C6-glioma regions of rat brain tissues with relatively large size can be differentiated clearly from normal brain tissues by this imaging system. The volume and location of the tumor region shown in the THz images are similar to those visualized macroscopically in the corresponding visual and H&E-stained images. Conclusion: We indicate terahertz horizontal-scanning ATR imaging technique with large effective imaging area, and high resolution could be used as an alternative method for label-free and high-sensitivity imaging of biological tissues.

中文翻译：

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生物组织的水平扫描衰减全反射太赫兹成像。

启示：太赫兹波由于其无创性和对水的高敏感性而成为生物组织的潜在工具。具有高灵敏度和无损特性的衰减全反射（ATR）已应用于THz成像。目的：我们旨在开发一种成像方法，以促进太赫兹ATR成像的实际应用。方法：我们已经展示了水平扫描太赫兹连续波ATR成像系统。通过优化ATR棱镜，有效成像面积与棱镜成像面一样大，可以很好地避免二次反射的影响。考虑到该系统的图像分辨率和稳定性，将棱镜底部的入射角选择为30度。结果：该系统在水平和垂直方向上的图像分辨率分别高达400和450μm。此外，通过该成像系统可以将正常大小的小鼠脑组织的U87-神经胶质瘤区域和相对较大的大小的大鼠脑组织的C6-神经胶质瘤区域与正常脑组织区分开。THz图像中显示的肿瘤区域的体积和位置与相应的视觉和H＆E染色图像中肉眼可见的相似。结论：我们表明太赫兹水平扫描ATR成像技术具有较大的有效成像面积，并且高分辨率可以用作生物组织的无标记和高灵敏度成像的替代方法。通过这种成像系统，可以将正常大小的小鼠脑组织的U87-神经胶质瘤区域和较大大小的大鼠脑组织的C6-神经胶质瘤区域与正常脑组织区分开。THz图像中显示的肿瘤区域的体积和位置与相应的视觉和H＆E染色图像中肉眼可见的相似。结论：我们表明太赫兹水平扫描ATR成像技术具有较大的有效成像面积，并且高分辨率可以用作生物组织的无标记和高灵敏度成像的替代方法。通过这种成像系统，可以将正常大小的小鼠脑组织的U87-神经胶质瘤区域和较大大小的大鼠脑组织的C6-神经胶质瘤区域与正常脑组织区分开。THz图像中显示的肿瘤区域的体积和位置与相应的视觉和H＆E染色图像中肉眼可见的相似。结论：我们表明太赫兹水平扫描ATR成像技术具有较大的有效成像面积，并且高分辨率可以用作生物组织的无标记和高灵敏度成像的替代方法。THz图像中显示的肿瘤区域的体积和位置与相应的视觉和H＆E染色图像中肉眼可见的相似。结论：我们表明太赫兹水平扫描ATR成像技术具有较大的有效成像面积，并且高分辨率可以用作生物组织的无标记和高灵敏度成像的替代方法。THz图像中显示的肿瘤区域的体积和位置与相应的视觉和H＆E染色图像中肉眼可见的相似。结论：我们表明太赫兹水平扫描ATR成像技术具有较大的有效成像面积，并且高分辨率可以用作生物组织的无标记和高灵敏度成像的替代方法。