The lungs are a pair of respiratory organs located in the thoracic cavity. Each lung has a cone shape and is divided into lobes and segments. The right lung has three lobes while the left has two. The lobes are further divided into bronchopulmonary segments, which are the basic functional units of the lung, each served by its own segmental bronchus, artery, veins, lymphatics and nerves. There are approximately 10 segments in each lung.

1. LUNGS &
BRONCHOPULMONARY
SEGMENTS
Shyambabu. P. Rauniyar
Lecturer
Dept of Anatomy
04/01/2015

2. LUNGS
 A pair of respiratory
organs situated in the
thoracic cavity and
invaginate into the
corresponding pleural
sac.
 Lungs are soft, spongy
and elastic
 Colour – rosy pink in
new born & dark gray
in adult.

3. GROSS FEATURES
 Shape – conical
 Weight – right –
700gm & left –
600gm ie. right is
heavier than left
lung
 Parts –apex, base,
surface - costal &
medial,
borders - anterior,
posterior & inferior

4. SURFACES & BORDERS

5. COSTAL SURFACE

6. LOBES & FISSURES
 Right lung: 3 lobes
 Upper lobe
 Middle lobe
 Lower lobe
Horizontal fissure
Oblique fissure
 Left lung: 2 lobes
 Upper lobe
 Lower lobe
Oblique fissure
6

7. STRUCTURES SEEN IN THE MEDIAL SURFACE OF LUNGS

10.  Hilus or (hilum)
 Indentation on mediastinal (medial) surface
 Place where blood vessels, bronchi, lymph vessel, and
nerves enter and exit the lung
 “Root” of the lung
 Above structures attaching lung to mediastinum
 Main ones: pulmonary artery and veins and main
bronchus
10
Medial view R lung Medial view of L lung

11. BLOOD SUPPLY
ARTERIAL SUPPLY VENOUS DRAINAGE
 Right side – one bronchial
artery branch from third
right posterior intercostal
artery
 Left side – two bronchial
arteries both are branch
from descending thoracic
aorta.
 Two bronchial veins on
each side.
 Right drain into azygos
vein.
 Left drain into hemiazygos
vein.

12. THE BRONCHIAL TREE
 System of tubes
formed from the
primary bronchi and
their branches is called
bronchial tree.
 Cartilage in walls
decrease and
smooth muscle
increase with
branching

13. Figure 23.10a
THE BRONCHI AND LOBULES OF THE LUNG
 Primary bronchi branch
into secondary or lobar
bronchi
 Secondary bronchus
goes to each lobe of
the lungs
 Secondary bronchi
branch into tertiary
bronchi
 Tertiary bronchi supply
air to a single
bronchopulmonary
segment

15. CHARACTERISTICS OF BRONCHOPULMONARY
SEGMENT
 The anatomic, functional, and surgical units
of the lung is known as bronchopulmonary
segments .
 Each segment receives air from an individual
segmental (tertiary) bronchus
 Approximately 10 bronchopulmonary segments
in each lung

16.  Each segments are pyramid shaped, with
its apex toward the lung root
 It has a segmental bronchus, a segmental
artery, lymph vessels, and autonomic
nerves
 The segmental vein lies in the connective
tissue between adjacent
bronchopulmonary segments

18. RIGHT LUNG
 Superior lobe:
Apical,
posterior,
anterior
 Middle lobe:
Lateral,
medial
 Inferior lobe:
Superior (apical),
medial basal,
anterior basal,
lateral basal,
posterior basal

19. LEFT LUNG
 Superior lobe:
Apical,
posterior,
anterior,
superior lingular,
inferior lingular
 Inferior lobe:
Superior (apical),
medial basal,
anterior basal,
lateral basal,
posterior basal

21.  On entering a bronchopulmonary segment,
each segmental bronchus divides repeatedly.
 The segmental bronchus is accompanied by a
branch of the pulmonary artery ie each
segment has separate artery.
 Pulmonary vein do not accompanied the
bronchi or arteries.
 Each segment has its own lymphatic vessels
and autonomic nerve supply.