Bickenbach Johannes, Dembinski Rolf, Czaplik Michael, Meissner Sven, Tabuchi Arata, Mertens Michael, Knels Lila, Schroeder Wolfgang, Pelosi Paolo, Koch Edmund, Kuebler Wolfgang M, Rossaint Rolf, Kuhlen Ralf
Department of Surgical Intensive Care, University Hospital RWTH Aachen, Germany.
J Clin Monit Comput. 2009 Oct;23(5):323-32. doi: 10.1007/s10877-009-9200-1.
In conventional in vivo microscopy, a three dimensional illustration of tissue is lacking. Concerning the microscopic analysis of the pulmonary alveolar network, surgical preparation of the thorax and fixation of the lung is required to place the microscope's objective. These effects may have influence on the mechanical behaviour of alveoli. Relatively new methods exist for in vivo microscopy being less invasive and enabling an observation without fixation of the lung. The aim of this study was to compare a fibered confocal laser scanning microscopy (FCLSM) with optical coherence tomography (OCT) in a mouse and a rabbit model. Moreover, FCLSM was also used endoscopically in the rabbit model.
Smallest possible thoracic windows were excised at the lower margin of the upper right lung lobe and an interpleural catheter inserted before re-coverage with a transparent membrane foil. The OCT-scanner was positioned by a motor driven translation stage. The imaging was gated to endinspiratory plateau. For CLSM, Fluorescein 0.1% was given into the central venous streak line. The confocal probe with a diameter of 650 microm was carefully positioned at the very same lung region. Images were directly recorded real-time and the observed region qualitatively compared with FD-OCT images. Additionally, in the rabbit model, CLSM was used endoscopically under bronchoscopic sight control. In a postprocessing analysis, images taken were analyzed and compared by using an "air index" (AI).
In the mouse model, the very same region could be re-identified with both techniques. Concerning alveolar shape and size, qualitatively comparable images could be gained. The AI was 40.5% for the OCT and 40.1% for the CLSM images. In the rabbit, even an endoscopic view on alveoli was possible. Likewise AI was 43.2% for CLSM through the thoracic window and 43.6% from endoscopically. For the OCT an AI of 44.6% was analysed in the rabbit model.
Both FD-OCT and CLSM provide high-resolution images of alveolar structure giving depth information that is beneficial to conventional microscopy. CLSM also facilitates endoscopic view on alveoli being well comparable to images gained through a thoracic window.
在传统的体内显微镜检查中，缺乏组织的三维图像。关于肺泡网络的显微镜分析，需要对胸部进行手术准备并固定肺，以便放置显微镜物镜。这些操作可能会影响肺泡的力学行为。存在一些相对较新的体内显微镜检查方法，其侵入性较小，能够在不固定肺的情况下进行观察。本研究的目的是在小鼠和兔模型中比较纤维共聚焦激光扫描显微镜（FCLSM）和光学相干断层扫描（OCT）。此外，FCLSM还在兔模型中用于内镜检查。
在右上肺叶下缘切除尽可能小的胸窗，并插入胸膜间导管，然后用透明膜箔重新覆盖。OCT扫描仪通过电机驱动的平移台定位。成像选在吸气末平台期。对于共聚焦激光扫描显微镜（CLSM），将0.1%的荧光素注入中心静脉纹线。将直径为650微米的共聚焦探头小心地放置在同一肺区域。图像实时直接记录，并将观察区域与频域光学相干断层扫描（FD-OCT）图像进行定性比较。此外，在兔模型中，CLSM在支气管镜直视控制下用于内镜检查。在后期处理分析中，使用“空气指数”（AI）对拍摄的图像进行分析和比较。
在小鼠模型中，两种技术都能重新识别同一区域。关于肺泡的形状和大小，可以获得定性可比的图像。OCT图像的AI为40.5%，CLSM图像的AI为40.1%。在兔中，甚至可以通过内镜观察肺泡。同样，通过胸窗的CLSM的AI为43.2%，内镜观察的AI为43.6%。在兔模型中，OCT的AI为44.6%。
FD-OCT和CLSM都能提供肺泡结构的高分辨率图像，并给出深度信息，这对传统显微镜检查有益。CLSM还便于对肺泡进行内镜观察，与通过胸窗获得的图像具有良好的可比性。
