Chu Kengyeh K, Unglert Carolin, Ford Tim N, Cui Dongyao, Carruth Robert W, Singh Kanwarpal, Liu Linbo, Birket Susan E, Solomon George M, Rowe Steven M, Tearney Guillermo J
Wellman Center for Photomedicine, Department of Determatology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St., Boston, MA 02114, USA; Contributed equally as co-authors.
Wellman Center for Photomedicine, Department of Determatology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St., Boston, MA 02114, USA.
Biomed Opt Express. 2016 Jun 2;7(7):2494-505. doi: 10.1364/BOE.7.002494. eCollection 2016 Jul 1.
We have designed and fabricated a 4 mm diameter rigid endoscopic probe to obtain high resolution micro-optical coherence tomography (µOCT) images from the tracheal epithelium of living swine. Our common-path fiber-optic probe used gradient-index focusing optics, a selectively coated prism reflector to implement a circular-obscuration apodization for depth-of-focus enhancement, and a common-path reference arm and an ultra-broadbrand supercontinuum laser to achieve high axial resolution. Benchtop characterization demonstrated lateral and axial resolutions of 3.4 μm and 1.7 μm, respectively (in tissue). Mechanical standoff rails flanking the imaging window allowed the epithelial surface to be maintained in focus without disrupting mucus flow. During in vivo imaging, relative motion was mitigated by inflating an airway balloon to hold the standoff rails on the epithelium. Software implemented image stabilization was also implemented during post-processing. The resulting image sequences yielded co-registered quantitative outputs of airway surface liquid and periciliary liquid layer thicknesses, ciliary beat frequency, and mucociliary transport rate, metrics that directly indicate airway epithelial function that have dominated in vitro research in diseases such as cystic fibrosis, but have not been available in vivo.
我们设计并制造了一种直径为4毫米的刚性内窥镜探头，用于从活体猪的气管上皮获取高分辨率的显微光学相干断层扫描（µOCT）图像。我们的共光路光纤探头采用了梯度折射率聚焦光学元件、一个选择性镀膜的棱镜反射器以实现用于增强焦深的圆形遮挡变迹，以及一个共光路参考臂和一台超宽带超连续谱激光器以实现高轴向分辨率。台式表征显示横向分辨率和轴向分辨率分别为3.4微米和1.7微米（在组织中）。成像窗口两侧的机械支撑轨可使上皮表面保持在焦点上，而不会扰乱黏液流动。在体内成像过程中，通过向气道气囊充气以将支撑轨固定在上皮上，减轻了相对运动。在后期处理过程中还实施了软件图像稳定化。所得图像序列产生了气道表面液体和纤毛周液体层厚度、纤毛摆动频率和黏液纤毛运输速率的配准定量输出，这些指标直接表明气道上皮功能，在诸如囊性纤维化等疾病的体外研究中占据主导地位，但在体内尚未获得。
