Dynamic micro functional analysis of biological tissue underneath the skin surface by high-speed optical coherence tomography

我们的研究目标是展示一种新型的高分辨率光学相干层析技术，用于测量生物组织的光学常数以及预测人体皮肤的老化。(1)A锁模Ti：采用蓝宝石激光器（飞秒激光器）作为高分辨率OCT的光源，通过补偿低相干干涉仪的色散不平衡，获得了3.1 μ m的飞秒激光相干长度。此外，利用光子晶体光纤获得了超连续谱光源。(2)In在长波区，采用一种新型宽带光源作为超高分辨率OCT光源，在中心波长1.3 μ m处相干长度为3.5 μ m。获得了离体生物组织的高分辨率OCT图像。(3)In为了获得焦点对准成像，我们使用了样品的聚焦透镜的聚焦效果。将共焦光学系统与OCT成像系统相结合，实现了聚焦OCT成像。成功获得了大于2.5mm的成像深度。(4)In实验中，利用高分辨率OCT清晰地观察了皮肤的表皮、真皮和基底层等微观结构，并获得了人体皮肤的活体高分辨率OCT图像。表皮厚度和基底层厚度随年龄增长而减少。(5)We开发了用于人体皮肤诊断的OCT探头。在实验中，使用OCT探头的OCT成像可以提供表皮、真皮和基底层的清晰成像，表明我们的探头可以用于诊断人体皮肤的老化。

Our research target is demonstration of a novel high-resolution optical coherence tomography for measurement of optical constant of biological tissue as well as prediction of aging of human skin.(1)A mode-locked Ti : sapphire laser (femto-second laser) is used as the light source of the high-resolution OCT. The coherence length of femto-second laser of 3.1μm was obtained by compensation of unbalance of chromatic dispersion of the low-coherence interferometer. Furthermore, supercontinuum light source was obtained by use of a photonic crystal fiber.(2)In the longer wavelength region, a novel broadband light was used as the light source of ultra high-resolution OCT. The coherence length was 3.5μm at the center wavelength of 1.3μm. In vitro high-resolution OCT image of biological tissue was obtained.(3)In order to obtain in-focus imaging, we used the focusing effect of the focusing lens of the sample. This method is called in-focus OCT, in which confocal optics is combined with OCT imaging system. The imaging depth of more than 2.5mm was successfully obtained.(4)In the experiment, micro-skin structures including the epidermis, dermis and stratum basale are clearly observed using high-resolution OCT. In vivo high-resolution OCT of human skin was also obtained. The thickness of epidermis as well as stratum basale decreased with aging.(5)We developed the OCT probe for diagnosis of human skin. In the experiment, the OCT imaging with the OCT probe can provide clear imaging of the epidermis, dermis and stratum basale, showing that our probe is useful for diagnosis of aging of human skin.