Download Bronchopulmonary Segments: Right Lung

Bronchopulmonary Segments: Right Lung
The bronchopulmonary segment is the anatomical, functional, and surgical unit/subdivision of
the lung and refers to the portion of the lung supplied by each segmental/tertiary bronchus and
segmental/tertiary artery. It consists of the segmental/tertiary bronchus, a segmental branch of
the tertiary artery, a segment of the lung tissue, and the surrounding connective-tissue septum.
The bronchopulmonary segment is important because a surgeon can remove one segment
without seriously disrupting surrounding segments.
There are 10 bronchopulmonary segments in the right lung (3 in superior lobe, 2 in middle lobe,
5 in inferior lobe) and 8-10 segments on the left (4-5 in upper lobe, 4-5 in lower lobe). Each
segment is separated from the others by a layer of connective tissue.
SUPERIOR LOBE - (Apical Lobe - RP-4-C3 with overlays) The bronchoscopic view, down the trachea and bronchus and the anatomical view from the
other end, are shown in the diagram RP-4-C5.
1. Apical Segmental Bronchus (colour code - red)
Directed vertically upwards and posteriorly with a lateral inclination to apex. Apical Segment constitutes apex of lung occupying the space roofed by the cupola.* Laterally it
extends to the second rib. Medially it borders on the mediastinum. In lateral view it is a
V-shaped segment with the apex at the hilum projecting towards the hilum.
2. Posterior Segmental Bronchus (colour code - green)
Directed backwards, laterally and slightly upwards.
Segment: 1/5
Bronchopulmonary Segments: Right Lung
- quadrilateral shaped segment
- inferior part - borders on oblique fissure laterally and posteriorly - chest wall related to two
to fourth ribs
3. Anterior Segmental Bronchus (colour code - blue)
Directed downward and forward (parallel to middle lobe bronchus).
Segment: - The segment is roughly quadrilateral in shape and extends from the hilum towards
periphery. The segmental bronchus is laying behind the fourth rib. Has two sub-segments:
- anterior sub-segment - bronchus runs in sagittal plane toward anterior chest wall. This is
a very shallow sub-segment.
- lateral sub-segment (axillary sub-segment) - lies in lateral and superior part of chest and is
commonly the site of disease.
("Intermediate bronchus" = portion of right bronchus between upper and middle lobe bronchi.)
*Cupola of the pleura is the dome where mediastinal and costal parts of parietal pleura become
continuous. It is further strengthened by a thickening of the endothoracic fascia - suprapleural
membrane.
2/5
Bronchopulmonary Segments: Right Lung
MIDDLE LOBE
4. Lateral Segmental Bronchus (colour code - yellow)
Directed antero-inferiorly into lateral chest wall.
Segment: - shape is triangular with apex directed toward hilum.
- forms a wedge between horizontal and oblique fissures.
Upper and lower borders:
- follow horizontal and oblique fissures rather more than half way toward their anterior
extremities. In lateral view the lateral segment lies mainly posterior to medial segment.
5. Medial Segmental Bronchus (colour code - brown)
Directed ventro-caudally.
Segment: - occupies medial part of horizontal fissure and merges with it at cardiac borders. Laterally
it occupies the costo-diaphragmatic angle (touches lower end of oblique fissure). Posteriorly (in
lateral view) it does not quite reach the hilum.
LOWER LOBE
3/5
Bronchopulmonary Segments: Right Lung
6. Superior Segmental Bronchus (colour code - purple)
Arises from the posterior aspect of the main bronchus at the level of the middle lobe bronchus,
and proceeds posteromedially. Segment -
is a posterior structure
PA view - ovoid in mid-lung fields
in lateral view it is triangular (pointing anteriorly)
the base T4 - T8 vertebrae
above - the upper part of the oblique fissure
below - ill defined
7. Medial Basal Bronchus (cardiac segment)(colour code - orange)
Runs downward and medially - forms a major portion of mediastinal surface of lower lobe
(cardiac segment) - small and separated from surface by other basal segments.
8. Anterior Basal Segment (colour code - blue)
Lies in the ventral part of the oblique fissure - occupies the same position as the lateral basal
segment in AP view.
9. Lateral Basal Segment (colour code - yellow)
Triangular - apex pointing to the hilum
- base occupying the costo-phrenic angle
10. Posterior Basal Segment (colour code - black)
Triangular - apex points to hilum
- base occupies middle two thirds of diaphragm
4/5
Bronchopulmonary Segments: Right Lung
Previous l RP4 Lung Segmentation: Home l Next
5/5