Perspectives using probe-based confocal laser endomicroscopy of the respiratory tract

QUESTIONS UNDER STUDY/PRINCIPLES: Although probe-based confocal laser endomicroscopy (pCLE) is on the edge of entering daily practice in gastroenterological endoscopy, findings in the field of respiratory medicine are only rarely reported, keeping pCLE during flexible bronchoscopy as a mere preclinical research tool. Since the endomicroscopic aspects of normal bronchial and alveolar tissue have recently been described, we want to take part in the development of a pCLE glossary, describing the pCLE features of pulmonary pathologies. METHODS: We recruited among patients referred for diagnostic bronchoscopy for pCLE imaging. Images from the central airways were obtained in every patient and alveoloscopy was performed in at least five sub-segments per patient. RESULTS: Using pCLE imaging, we were able to discriminate normal from abnormal endomicroscopical patterns in four respiratory conditions. These findings were matched with classical histopathology. CONCLUSION: Reflecting on our own experience using pCLE imaging, we summarise the present state of knowledge, discuss five clinical cases and discuss current limitations and the future promise of this novel imaging tool.