Optical + Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, University of Western Australia, Crawley, Western Australia, Australia.
J Appl Physiol (1985). 2012 Sep;113(6):967-74. doi: 10.1152/japplphysiol.00051.2012. Epub 2012 Jul 5.
Imaging of alveoli in situ has for the most part been infeasible due to the high resolution required to discern individual alveoli and limited access to alveoli beneath the lung surface. In this study, we present a novel technique to image alveoli using optical coherence tomography (OCT). We propose the use of OCT needle probes, where the distal imaging probe has been miniaturized and encased within a hypodermic needle (as small as 30-gauge, outer diameter 310 μm), allowing insertion deep within the lung tissue with minimal tissue distortion. Such probes enable imaging at a resolution of ∼12 μm within a three-dimensional cylindrical field of view with diameter ∼1.5 mm centered on the needle tip. The imaging technique is demonstrated on excised lungs from three different species: adult rats, fetal sheep, and adult pigs. OCT needle probes were used to image alveoli, small bronchioles, and blood vessels, and results were matched to histological sections. We also present the first dynamic OCT images acquired with an OCT needle probe, allowing tracking of individual alveoli during simulated cyclical lung inflation and deflation.
由于需要高分辨率才能分辨单个肺泡，并且难以接近肺表面以下的肺泡，因此原位肺泡成像在很大程度上是不可行的。在这项研究中，我们提出了一种使用光学相干断层扫描（OCT）成像肺泡的新方法。我们建议使用 OCT 针探头，其中将远端成像探头微型化并封装在皮下注射针（小至 30 号，外径 310μm）中，以便在最小组织变形的情况下将其插入肺组织深处。这种探头能够以 12μm 的分辨率在以针尖端为中心的直径约为 1.5mm 的三维圆柱视野内进行成像。该成像技术在来自三个不同物种的离体肺上进行了验证：成年大鼠、胎羊和成年猪。使用 OCT 针探头对肺泡、小细支气管和血管进行成像，并将结果与组织学切片进行匹配。我们还展示了首次使用 OCT 针探头获得的动态 OCT 图像，这些图像允许在模拟的周期性肺膨胀和萎陷过程中跟踪单个肺泡。
