Right Upper Lobe: Posterior Segment (S2)




(1)
IMM, Curie-Montsouris Thorax Institute, Paris, France

 




9.1 Anatomical Landmarks



Bronchus

As it enters the parenchyma, the upper lobe bronchus triplicates into three segmental bronchi: apical (B1), posterior (B2), and anterior (B3). B1 and B2 can originate separately or as a common trunk (B1+2) (◘ Fig. 9.1a).

A192284_2_En_9_Fig1_HTML.jpg


Fig. 9.1
Anatomical landmarks. a segmental bronchus (posterior view), b arterial supply to the posterior segment (posterior view), c venous drainage (anterior view)


Arteries

The posterior segment is supplied by the ascending A2 (Asc.A2) that originates within the fissure from the posterior aspect of the pulmonary artery, opposite the middle lobe artery (◘ Fig. 9.1b). It ascends to S2 and lies posteriorly to the lobar bronchus. In the majority of patients, there is only one artery, while there are none or two in some patients.


Veins

In most cases, the segmental veins of the upper lobe are the two upper tributaries of the upper lobe vein:



  • V1 is the uppermost branch and is found in the hilum of the upper lobe. It is the most anterior and superior vessel.


  • V2+3 is the central vein and runs in the parenchyma and within the fissure. It gives a large posterior branch for V2 and small tributaries for V3. Actually, when V2 is large, it also provides branches to S1. It is recommended to divide only its most posterior branch.


9.2 Variations and Pitfalls




Jan 15, 2018 | Posted by in RESPIRATORY | Comments Off on Right Upper Lobe: Posterior Segment (S2)

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