| |
| 
|
According to the course of the conduits, the right lung is divided into 10 segments. The right lower lobe consists of 5 bronchopulmonary segments:
- The apical segment S6
- The mediobasal segment S7
- The anterobasal segment S8
- The laterobasal segment S9
- The posterobasal segment S10
Bronchus B7 and B8: The right lower lobe bronchus consists of the bronchus of the apical segment S6 and the common trunk of the 4 basal lower lobe segments. The first branching is the B6 bronchus. Approximately 1.5 cm below the B6 branching is the common trunk of the 4 basal segment bronchi, which then continue in different directions. The uppermost branch of these is B7, originating 15 mm caudal from B6 in an anteromedial direction. Often, there is a fusion of the parenchyma it supplies with that of the middle lobe. About 5 mm after B7, B8 originates in an anterolateral direction.
Arteries A7 and A8: At the base of the fissure between the upper and middle lobes runs the pars interlobaris of the right pulmonary artery. The lower lobe artery is a continuation of the pars interlobaris. In the majority of cases, after a branch to the 6th segment A6, the first anterior branch of the basal artery is the segmental artery A7, and the second branch is the segmental artery A8. The remaining basal artery then divides into a laterobasal branch A9 and a posterobasal branch A10.
Veins V7 and V8: The segmental vein V7 runs medial to B7 and empties at the caudal edge of the lower pulmonary vein. The segmental vein V8 runs caudal to B8 as well as ventral to B9 and B10 and empties into the superior basal vein.