1. Pulmonary Collapse
DR. NIKHIL MURKEY

2. Definitions
 Collapse or atelectasis is the complete or partial loss
of volume of lung.

3. Collapse
 Mechanisms
 Relaxation /
passive
 Cicatrization
 Adhesive
 Resorption

4. Causes of collapse
Due to endobronchial obstruction:
 Intrinsic
 Broncogenic carcinoma
 Adenoid cytic carcinoma
 Metastasis
 Lymphoma
 Benign tumours
 Granulomatous diseases (TB, sarcoidosis)
 Miscellaneous conditions (aspirated foreign bodies, mucus
plugs, gastric contents, malpositioned endotracheal
tube, bronchial torsion or rupture, amyloidosis, Wegener’s)

5.  Extrinsic
 Hilar or mediastinal lymphadenopathy
 Mediastinal mases
 Fibrosing mediastinitis
 Aortic aneurysms and congenital vascular anomalies
 Cardiac enlargement
Lobar collapse without endobronchial obstuction d/t
pleural diseases, radiation induced collapse, tumour
replacement (bronchoalveolar cell carcinoma).

6. Radiological signs of collapse
 Direct
 Displacement of interlobar fissures
 Loss of aeration
 Vascular or bronchial crowding

7. Radiological signs of collapse
 Indirect
 Elevation of hemidiaphragm
 Mediastinal displacement
 Hilar diaplacement
 Compensatory hyperinflation

8.  Frontal and lateral chest radiographs. The cause of the collapse is a
bronchogenic carcinoma; the endobronchial component is visible as an
abrupt cut-off of the left main bronchus. There is marked displacement
of the right lung anteriorly and posteriorly across the midline (arrows).
Note the marked anterior hyperlucency of the thorax on the lateral view.

9.  Herniation of
both retrosternal
lung and azygo-
esophageal
reflection.

10.  Complete collapse of the
left lung.
 The tip of the
endotracheal tube is
beyond the carina and
down the right
bronchus, causing
collapse of the left lung
and compensatory
hyperinflation of the
right lung which has
herniated across the
midline.

11.  Total right lung collapse in a neonate. The patient
was ventilated for respiratory distress syndrome and
the cause of the total lung collapse was a mucus plug

12. Signs in collapse
 Shifting granuloma sign: change in position of the
granuloma d/t hyperinflation

13.  Luftsichel sign: overinflated segment of the ipsilateral lower lobe
occupies the space between the mediastinum and the medial aspect
of the collapsed upper lobe resulting in a paramedian translucency.
This sign is commoner on the left side.

14.  Juxtaphrenic peak
sign: upper lobe
collapse (both upper
and middle lobe on
the right side) causes
a small triangular
density at the highest
point of the dome of
diaphragm d/t
traction and
reorientation of
inferior accessory
fissure.

15.  Golden S sign: the
combination of
collapse and mass
centrally results in
a focal convexity
with a concave
outine
peripherally (sign
is useful only for
right upper lobe
and bilateral lower
lobe)

16.  CT equivalent
of Golden S
sign: concavity
of fissure with
adjacent
convexity
(useful in all
lobes), highly
suggestive of
bronchogenic
carcinoma.

17.  CT mucus bronchogram sign: on contrast enhanced CT there
are low attenuation areas within the high attenuation collaped
lung representing inspissated secretions in airways.

18.  Superior triangle sign:
triangular density to the
right of mediastinum seen
in right lower lobe
collapse d/t displacement
of anterior junctional
structures.

19. Right upper lobe

20. Right upper lobe

21. Tight right upper lobe collapse. Note how the collapsed
lobe (due to a central bronchogenic carcinoma) results
in increased right paramediastinal density

23. Left upper lobe

26. Right middle lobe

27. Right middle lobe

28. Lingular lobe

29. Right lower lobe

30. Right lower lobe

31. Left lower lobe

32. Left lower lobe

33.  Flat waist sign: seen in extensive collapse of
the left lower lobe d/t flattening of the aortic
knuckle and main pulmonary artery d/t
cardiac rotation and displacement to the left.

34. Round atelectasis

35.  Combined right middle and right lower lobe collapse. On the frontal view the
increased density extends to the right costophrenic angle. On the lateral view the
increased density also extends from the anterior to the posterior chest wall. The
cause in this case was a bronchogenic carcinoma obstructing the bronchus
intermedius

36.  Bilateral lower
lobe collapse.
Bilateral
triangular
densities are
seen with
obscuration of
the medial
portions of the
hemidiaphragm
s. The cause was
mucous
plugging

37. Consolidation
 Defined as the decreased volume of air in the lung,
with normal lung volume.

38. Common causes
 Pnemonia
 Cardiogenic/non cardiogenic pulmonary edema
 Hemorrhage
 Aspiration
 Neoplasms like alveolar cell carcinoma
 Alveolar proteinosis

39.  Air bronchogram sign: It is produced by the
radiographic contrast between the column of air in
airway and the surrounding opaque acini.

40. Pattern of consolidation on plain film

41. Right upper lobe consolidation

42. Right middle lobe consolidation

43. Right lower lobe consolidation

44. Lingular lobe

45. Left upper lobe consolidation

46. Left lower lobe consolidation

47. Thank you