segmental bronchus four (left superior lobe)
Last reviewed 01/2018
The superior lingular segmental bronchus of the left superior lobe bronchus ramifies to form the bronchial tree of the superior lingular bronchopulmonary segment of the superior lobe. The lingular bronchopulmonary segments, four and five, are very rarely demarcated as a separate lobe that is equivalent to the right middle lobe.
The superior lingular bronchopulmonary segment is supplied uniquely by the superior lingual segmental bronchus; it forms a discrete functional unit.