For medical, nursing and physiotherapy undergraduates, and postgraduates

1. LUNGS
DR. SUNDIP CHARMODE
ASSOCIATE PROFESSOR
DEPARTMENT OF ANATOMY
AIIMS RAJKOT

2. INTRODUCTION
• They are a pair of essential organs and invaginate into
the corresponding pleura.
• Each lung is invested by pulmonary pleura except at
the hilum and the attachment of the pulmonary
ligament.

3. CHARACTERISTIC FEATURES
1. Lung is porous, elastic and spongy in texture.
2. It crepitates to the touch and floats on water.
3. In newborn, it is rosy pink and in adults – dark, slaty
grey.

4. PRESENTING PARTS
• Half conical in shape
• Apex
• Base
• Surfaces: Costal and medial
• Borders: Anterior, Posterior and Inferior

5. RELATIONS

7. APEX OF LUNG
Not a point but an area
above the first rib and
its cartilage.
The summit is 3-4 cm
above the first costal
cartilage and 2-5 cm
above the medial end
of clavicle.

8. ANTERIOR RELATIONS
1. Subclavian artery arches upwards and laterally
below the summit of the apex and lodges in a
groove.
2. The origin of internal thoracic artery
3. Scalenus anterior muscle close to its insertion
4. Subclavian vein lodges in a groove below and in
front of subclavian artery, and separated by scalenus
anterior.

9. POSTERIOR RELATIONS
• Apex is in contact with the neck of 1st rib and
following structures intervene between them (medial
to lateral)
1. Sympathetic trunk
2. First posterior intercostal vein
3. Superior intercostal artery
4. Ascending branch of ventral ramus of 1st thoracic
nerve

10. LATERAL RELATIONS
1. Scalenus medius and
2. Lower trunk of brachial plexus

11. MEDIAL RELATIONS
RIGHT LUNG
1. Right brachio-cephalic
vein with right phrenic
nerve and peri-cardio-
phrenic vessels
2. Brachio-cephalic trunk
3. Trachea with right
vagus nerve
LEFT LUNG
1. Left brachio-cephalic
vein
2. Left subclavian artery
3. Left edge of esophagus
4. Thoracic duct

12. BASE
• Concave and semilunar in shape
• Right lung base is more concave than left lung
• Relations:
1. Upper surface of corresponding half of diaphragm
separated by the pleural sac
2. Below the diaphragm
• Right side – right lobe of liver;
• Left side – left lobe of the liver, fundus of stomach
and spleen

13. COSTAL SURFACE
• Convex, smooth and related with
lateral thoracic wall
• Separated by costal pleura and
endo-thoracic fascia.
• Presents impressions of ribs and
costal cartilages, and elevations for
intercostal spaces.
– Mid-clavicular line: Upper six
ribs
– Mid-axillary line: Upper eight
ribs
– Scapular line: Upper ten ribs

17. ANTERIOR BORDER
• Thin, sandwiched
between anterior
thoracic wall and
pericardium.
• Occupies the Costo-
mediastinal recess of
pleura.

18. POTERIOR BORDER
• Thick, rounded as it
occupies the para-
vertebral border.
• Related with anterior
margin of heads of upper
ten ribs, sympathetic
trunk, and origins of
greater and lesser
splanchnic nerves.

19. INFERIOR BORDER
• Circumscribed border
which separates the base
of the lung from the costal
and medial surfaces.
• Posterior and lateral part
of the border is thin as it
occupies costo-
diaphragmatic recess of
pleura.

20. MEDIAL SURFACE
Posterior or Vertebral part
• Flat
• Related with the bodies and
intervertebral discs of upper
ten thoracic vertebrae
• Posterior intercostals vessels,
Greater and Lesser
splanchnic nerves in lower
part.

21. ANTERIOR OR MEDIASTINAL PART – RIGHT
LUNG
1. Hilum of lung: triangular non-pleural impression through
which structures of lung root enter and leave the organ.
• From above downwards: upper lobe bronchus, pulmonary
artery, principal bronchus, lower pulmonary vein.
• From before backwards: upper pulmonary vein, pulmonary
artery, bronchus
2. Pulmonary ligament: consists of a bilaminar fold of
mediastinal pleura and extends from esophagus to lung
below the hilum.
• Contain loose areolar tissue, some lymph vessels,
occasionally accessory bronchial artery.
• Lower margin of the ligament is free.

23. ANTERIOR OR MEDIASTINAL PART – RIGHT
LUNG
3. Cardiac impression: anterior surface of right auricle,
anterior and right surface of right atrium, part of right
surface of right ventricle covered by pericardium.
4. Right phrenic and pericardiophrenic vessels – in front of
hilum
5. Terminal part of inferior venacava along with right phrenic
nerve
6. Superior venacava in lower part of groove, and right
brachio-cephalic vein in upper part.
7. Arch of azygous vein
8. Brachiocephalic trunk, before it divides into right
subclavian and common carotid arteries
9. Right side of trachea with right vagus nerve
10. Right edge of esophagus

27. ANTERIOR OR MEDIASTINAL PART – LEFT
LUNG
1. Hilum of lung: triangular non-pleural impression through
which structures of lung root enter and leave the organ.
• From above downwards: Pulmonary artery, left principal
bronchus, lower pulmonary vein.
• From before backwards: upper pulmonary vein, pulmonary
artery, bronchus
2. Pulmonary ligament: consists of a bilaminar fold of
mediastinal pleura and extends from esophagus to lung
below the hilum.
• Contain loose areolar tissue, some lymph vessels,
occasionally accessory bronchial artery.
• Lower margin of the ligament is free.

29. ANTERIOR OR MEDIASTINAL PART – LEFT LUNG
3. Cardiac impression: anterior and left surfaces of left
ventricle, and left auricle. Anterior surface of a part of right
ventricle covered by pericardium.
4. Left phrenic and pericardiophrenic vessels pass between
mediastinal pleura and pericardium.
5. Groove passing upwards from upper part of cardiac
impression lodges pulmonary trunk.
6. A well-defined groove arching backwards above the hilum
lodge arch of aorta.
7. Between arch of aorta and lung following structures
intervene:
– Nerves (before backwards): Left phrenic nerve, inferior cervical
cardiac branch of left vagus and superior cervical branch of left
sympathetic trunk, left vagus nerve
– Vein left superior intercostal vein

31. ANTERIOR OR MEDIASTINAL PART – LEFT LUNG
8. Descending thoracic aorta
9. A well-defined vertical groove for left subclavian artery
10. In front of the artery, a shallow groove for left brachio-
cephalic vein.
11. Above the aortic arch and behind the left subclavian artery,
left edge of esophagus and Thoracic duct.
12. A shallow groove running down and forwards between
pulmonary ligament and DTH - left edge of esophagus.

34. ROOT OF LUNG

37. LOBES AND FISSURES OF LUNG
• Right lung: three lobes – upper, middle and lower
• Left lung: two lobes – upper and lower
• Fissures:
– Oblique
– Horizontal

40. AZYGOUS LOBES OF LUNG
• Accessory or
supernumerary lobes
• Three types:
– Upper azygous lobe
– Lower azygous lobe
– Lobe of azygous vein
• Lobe of azygous vein:
1%

41. ROOT OF LUNG
• The root of each lung consists of a
tubular sheath of mediastinal
pleura and connects the hilum of
the lung with the heart and
trachea.
• Lies opposite 5th, 6th and 7th
thoracic vertebra
• The root contains:
– Principal bronchus
– Pulmonary vessels
– Bronchial vessels
– Lymphatics and nerves

42. DIFFERENCES BETWEEN TWO LUNGS
RIGHT LUNG LEFT LUNG
Shorter, wider, more capacious Longer, narrower and less capacious
Weight – 625 grams/ 20 oz. Weight – 565 grams/ 18 oz.
Three lobes with two fissures Two lobes with one fissure
Base more concave Base shallow
Absence of cardiac notch Presence of cardiac notch
Arrangement of structures at hilum (above –
downwards) – bronchus, artery, bronchus
and vein
Artery, bronchus and vein
Cardiac impression shallow Deep
Lingula absent Lingula present – corresponds to middle
lobe
Supplied usually by one bronchial artery Supplied usually by two bronchial artery

43. DIFFERENCES BETWEEN TWO LUNGS
RIGHT LUNG LEFT LUNG
Presents ten (10) broncho-pulmonary
segments
Three - upper lobe
Two- middle lobe
Five – lower lobe
Presents ten (10) broncho-pulmonary
segments
Five - upper lobe
Five – lower lobe

44. NUTRITION OF LUNG
• Conducting part: up to the beginning of respiratory
bronchioles – supplied by Bronchial arteries.
• Respiratory part: supplied by pulmonary arteries
via the pulmonary capillary plexus.

45. VENOUS DRAINAGE
• Two systems: Superficial and Deep
• Superficial veins: blood from pulmonary pleura,
extra-pulmonary bronchi and hilar lymph nodes –
– Right lung - Arch of azygous vein.
– Left lung – left superior intercostal vein.
• Deep veins: blood from intra-pulmonary bronchi
and bronchioles around the pulmonary vessels and
along the inter-lobular septa – pulmonary veins –
left atrium

46. LYMPHATIC DRAINAGE
• Superficial set: lie beneath the pulmonary pleura
around extra-pulmonary bronchi - drain into
broncho-pulmonary lymph nodes at hilum
• Deep set: lie beneath the pulmonary pleura around
intra-pulmonary bronchi and bronchioles - drain
into broncho-pulmonary lymph nodes at hilum

47. NERVE SUPPLY
• Anterior pulmonary plexus
• Posterior pulmonary plexus

48. BRONCHIAL TREE

49. BRONCHO-PULMONARY
SEGMENTS

52. FEATURES
1. Well defined, anatomic ,functional and
surgical sectors of lung.
2. Each segment is aerated by a tertiary or
segmental bronchus.
3. Each segment is Pyramidal in shape with
Apex directed towards the Root of the Lung.
4. Segmental venules lie in connective tissue
between adjacent units of Broncho-
pulmonary segments.

53. FEATURES
5. During Segmental Resection, the surgeon
works along the Segmental veins to isolate a
particular segment.
6. Branches of Pulmonary artery accompany the
Bronchi and lie Dorso-lateral to the
Bronchus.
7. Thus each segment has its own separate
artery.
8. Pulmonary veins run in inter-segmental
planes.

54. FEATURES
9. Pulmonary veins do not accompany the
bronchi or pulmonary arteries.
10. Each segment is having more than one vein,
or each vein drains more than one segment.
11. Broncho-pulmonary segment is not a
Broncho-vascular segment.

55. CONTENTS OF SEGMENT
 Each segment consists of :
1. Segmental bronchus
2. Segmental artery
3. Autonomic nerves
4. Lymph vessels

56. DISTAL PORTION OF
BROCHO-PULMONARY
SEGMENT

59. APPLIED ANATOMY
1. Infection of a Broncho-pulmonary segment
remains restricted except
2. Knowledge of anatomy of segments is
required for :
– Segmental resection
– During Bronchoscopy
3. Carina
4. Paradoxical respiration
5. Tuberculosis of lung

60. APPLIED ANATOMY
6. Bronchial asthma
7. Auscultation of lung
8. Most dependent Broncho-pulmonary segment
– Superior segment of Lower lobe in supine
position. Hence ?