| Interstitium of respiratory bronchiole Including respiratory bronchiolar wall, peribronchiolar and perivascular connective tissue, and associated vessel walls. |
| As noted above, Niewoehner and colleagues observed that the alveolar walls adjacent to the respiratory bronchiole could show fibrosis. |
| The acinus or primary pulmonary lobule consists of one terminal bronchiole, two to five generations of respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli. |
| The terminal respiratory unit of the lung from the respiratory bronchiole to the alveolus is called the acinus. |
| Each lobule contains a bronchiole and affiliated branches, a thin wall, and clusters of alveoli. |
| The scar of the obstructed bronchiole is inglobated in the wall of the free bronchiole. |
