ELN and lung carcinoma: Although some indirect abnormal pCLE patterns in patients with lung cancer have been described (dark hollows, elastin disorganisation and cellular infiltrates), pCLE imaging was unable to directly visualise the individual tumour cells despite fluorescein use.22–26 We attribute this lack of visualisation to the limited penetration depth of the surface-scanning approach and the thickness of the image plane (50 μm) of the CLE probe (AlveoFlex) that causes overlap of cells.