Pan Y, Farkas D L
J Biomed Opt. 1998 Oct;3(4):446-55. doi: 10.1117/1.429897.
We demonstrate the potential of optical coherence-domain tomography (OCT) for noninvasive imaging of living skin simultaneously at two wavelengths in the near infrared range (830 and 1285 nm). The technical details of a prototype monomode fiber-optic coherence tomographic scanner providing rapid two-dimensional (2D) and three-dimensional (3D) imaging of biological tissues are described. The effects of both instrumentation parameters and the dynamic characteristics of living tissue on image contrast and resolution and on speckle reduction are discussed. The impact of imaging speed on OCT image quality is studied by a comparison between a single scan and the corresponding frame-averaged OCT images, with the latter resulting in decreased speckle noise as well as loss of some subtle structures. Both theoretical predictions and experimental results in human skin imaging show that longer wavelength can minimize the influence of multiple scattering on image contrast and resolution and thus increase the effective penetration depth of OCT imaging to about 2 mm. Some high-resolution 2D and 3D images of microscopic anatomic structures of living human skin are presented and analyzed, illustrating the unique capability of OCT for in depth, noninvasive visualization of living skin microscopic morphology in vivo. © 1998 Society of Photo-Optical Instrumentation Engineers.
我们展示了光学相干域断层扫描（OCT）在近红外范围（830和1285纳米）的两个波长下同时对活体皮肤进行无创成像的潜力。描述了一种提供生物组织快速二维（2D）和三维（3D）成像的单模光纤相干断层扫描原型扫描仪的技术细节。讨论了仪器参数和活体组织的动态特性对图像对比度、分辨率以及散斑减少的影响。通过单次扫描与相应的帧平均OCT图像之间的比较，研究了成像速度对OCT图像质量的影响，后者会导致散斑噪声降低以及一些细微结构的丢失。人体皮肤成像的理论预测和实验结果均表明，较长波长可将多次散射对图像对比度和分辨率的影响降至最低，从而将OCT成像的有效穿透深度增加至约2毫米。展示并分析了一些活体人体皮肤微观解剖结构的高分辨率2D和3D图像，说明了OCT在体内对活体皮肤微观形态进行深度、无创可视化的独特能力。©1998年光电仪器工程师协会。
