Fig. 4

In vivo endobronchial imaging of sheep small airways. a Cut-away view of a reconstructed three-dimensional (3D) image of an 8 mm-long sheep small airway with the en face projection view of blood vessels overlaid on the inner surface of the three-dimensional (3D) image. b Representative in vivo 2D image of the peripheral sheep airway corresponding to the cross section indicated with the green dashed line in a. c 3× enlarged view of the area boxed with red dashed lines in b. d Representative in vivo 2D image of the sheep small airway, which is relatively more towards the proximal side (indicated with the blue dashed line in a). e 3× enlarged view of the area boxed with red dashed line in d. f Corresponding hematoxylin and eosin (H&E) histology. A: alveoli; BV: blood vessel; C: cartilage; EP: epithelium; LP: lamina propria; S: smooth muscle. All scale bars are 250 µm. Adapted with permission from Ref. [85].