In vivo assessment of alveolar morphology using a flexible catheter-based confocal microscope

Investigating the structure and function of alveoli in vivo is crucial for understanding the normal and diseased lungs. The authors image the alveoli of mice in vivo using a custom fibre optic catheter-based laser scanning confocal microscope. Images obtained using this system are analysed with an automated software application for alveolar size, wall thickness and number. Results show that direct dynamic visualisation of alveoli and surrounding structures is possible in vivo, with high resolution. Early results indicate high heterogeneity in alveolar structure in vivo, as opposed to an ordered uniform structure. Using the techniques presented here, there is great promise for advancing our knowledge of the functional unit of the lung, the alveolus, for alveolar mechanics, cell traffic and three-dimensional structural visualisation.