The document discusses lung collapse (atelectasis) and consolidation. Collapse is a loss of lung volume while consolidation involves fluid filling the alveoli. Collapse can be caused by obstruction of airways or loss of contact between the lungs and chest wall. Consolidation is seen in conditions like pneumonia. Specific patterns of collapse and consolidation are seen on chest x-rays depending on the affected lung lobe. Signs like fissure shifts and volume changes in the unaffected lobes help identify the collapsed lobe.

1. Collapse &
Consolidation

2. Collapse / Atelectasis
 Lung collapse refers to the complete or partial loss of
normal aeration and associated loss of volume(akin to
deflating a balloon).

3. Consolidation
 The term consolidation refers to the
displacement of the air in the alveoli, smaller
bronchi, and bronchioles, by exudate or
edematous fluid.

4. Important Features
 Collapse & consolidation can occur independently or
together.
 Collapse can be partial or complete.
 Extent of appearance due to collapse or consolidation or
both is often not clear.

5. Association/ Broad Aspect
 Consolidation Without volume loss:
---Pneumonia, Pulmonary edema,
Hemorrhage.
 Consolidation With volume loss:
---“Atelectasis” or “Collapse”

6. Consolidation With volume loss

7. Consolidation Without volume loss

8. Types of collapse
 Obstructive
 Non- Obstructive

9. Causes of Obstructive collapse
 Blockage of an airway…
Causes:
 1). Bronchogenic carcinoma
 2). Bronchial carcinoid
 3). Metastases to the bronchi
 4). Lymphoma
 5). Tuberculosis
 6). Left atrial enlargement from mitral stenosis
 7). Foreign body obstruction
 8). Main stem bronchus intubation

10. Causes of Non-Obstructive collapse
 Loss of contact between the parietal and visceral
pleura,
 Parenchymal compression,
 Loss of surfactant,
 Replacement of lung tissue by scarring or
infiltrative disease.

11. Mechanism of Atelectasis
 Resorption
 Relaxation
 Adhesive
 Cicatrization

12. Resorption Collapse
Air retained distal to occlusion is resorbed from the
non ventilated alveoli in obstructive type of
atelectasis. Over time, affected area becomes
totally airless causing alveolar collapse.

13. Relaxation Collapse
Contact between parietal & visceral pleurae is
eliminated.
Lung tends to retract towards its hilum when air or
fluid collects in the pleural space.
1). Pleural effusion
2). Pneumothorax
3). Hydrothorax, hemothorax
4). Diaphragmatic hernia
5). Pleural masses (including metastases and
mesothelioma)

14. Adhesive Collapse
 Induced by surfactant dysfunction.
 Decreased production or inactivation of
surfactant leads to alveolar instability and
collapse although central airways remain
patent.
 Respiratory distress syndrome of premature
infants, ARDS, acute radiation pneumonitis, PE
and lung contusion.

15. Cicatrisation Collapse
 Diminution of volume as a sequel of severe
parenchymal scarring.
Etiologies include:
 granulomatous disease
 late sequelae of TB
 necrotizing pneumonia
 radiation
 pneumoconiosis
 Collagen vascular diseases (e.g.
scleroderma, rheumatoid lung)

16. Signs Of Collapse
 Lobar:
 Shift of fissures
 Crowding of vessels (increased opacity)
 Extra lobar:
 Hemi diaphragm elevation.(Juxtaphrenic peak sign)
 Mediastinal shift towards side of collapse
 Hilar shift and distortion(Katan’s triangle sign)
 Compensatory contra-lateral hyperinflation
 Rib approximation.
 Obscuring of structures adjacent to collapsed lung,
such as the diaphragm, heart, or pulmonary vessels.

17. Causes Of Consolidation
 Acute pneumonia.
 Chronic Pneumonia:
------ Bacterial.
------ Lipoid.
------ Aspiration.
 Pulmonary Hemorrhage.
 Bronchoalveolar carcinoma.
 Alveolar proteinosis.

18. Radiological Features of
Consolidation
 Increased density.
 Acinar shadow.
 Silhouette sign.
 Air bronchogram.
Distribution of consolidation can vary widely.
 Can be described as “patchy”, “homogenous”, or
generalized”.
 Can be described as focal or by the lobe or segment
of lobe affected.

21. The left lung has •1 fissure
•2 lobes
The left lung has
•1 fissure
•2 lobes

22. The right lung has
The right lung has
•2 fissures
•3 lobes

23. RUL Anatomy

24. RUL Consolidation
 RUL consolidation will be seen as
an increased opacity within the
shaded area. Opacity may be
sharply bordered by the horizontal
fissure
 Some loss of outline of upper
right heart border may be apparent

25. •Dense opacity seen
above the horizontal
fissure.
•Air-bronchogram
line
•The lower border of
the consolidation is
sharply delinated by
the horizontal
fissure,suggesting
ant segment
involvement.

26. Dense opacity in the RUL
sharply bordered by the
horizontal and oblique
fissures suggesting
involvement of the anterior
and posterior segments of
the RUL

27. RUL Collapse
 RUL collapses toward ant, sup &
medial portion of chest.
 Medial collapse may mimic a right
paratracheal mass
 Lateral collapse lead to peripheral
mass-like opacity mimicking a
loculated pleural effusion.
 Right middle & lower lobes hyper
expand superiorly & medially.

29. Signs Of RUL Collapse
 S Sign of Golden.
 Juxta-phrenic peak sign.

30. S Sign of Golden - Refers to reverse
"S" shape of minor fissure in RUL
collapse due to a central obstructing
mass. Sup portion of "S" form displaced
minor fissure, while inf. portion results
from mass itself.

31. Juxtaphrenic
Peak - triangular
opacity
sometimes seen
over medial
portion of
diaphragm. Also
seen in cases of
RUL lobectomy.
Results from
superior
displacement of
inferior accessory

32. RML Anatomy

33. RML Consolidation
Seen as an area of
increased opacity in the
shaded area
•Loss of the definition of the
right heart border is often
seen

34. RML consolidation is
characteristically seen as a
wedge opacity in the lateral
view
•May be sharply bordered by the
horizontal and oblique fissures

35. RML Collapse
 RML collapse relatively easy to
identify on lateral view,
appearing as a triangular
opacity in anterior aspect of
chest, overlying cardiac
shadow.
 On frontal radiographs findings
are subtle.
--- Normal horizontal fissure no
longer visible (as it rotates down)
--- Blurring of right heart border.

38. RML Collapse Syndrome
 Frequently non-obstructive
 Accompanied by scarring and bronchiectasis
 Often found in elderly women
 Chronic cough is most common symptom.
 Hemoptysis, chest pain and dyspnoea are also
reported .
 Associated with blurring of right heart border.

40. RLL Anatomy
Right lower lobe comprises of 5 pulmonary
segments. Its a large lobe & will provide varying
patterns of consolidation depending on
segments involved.
Note that consolidation of the
apical segment will not result
in loss of the diaphragmatic
outline.

41. RLL Consolidation
•Loss of right hemi-diaphragm
•Dense opacity in RLL
•Some loss of right heart
border

42. •Increased triangular opacity
within the RLL
•Commonly seen with loss of the
right hemi-diaphragm

43. RLL Collapse
 Collapse is in post, med & inf
direction.
 Major fissure swings down
&backward.
 Hilum is displaced inferiorly.
 Hemidiaphragm is elevated.
 On PA view a triangular opacity
adjacent to spine with base on
hemidiaphragm.
 On lateral view there is
increased opacity over lower
thoracic vertebrae .

44. RLL Collapse
 Another indirect sign is vascular nodular sign, due to
compensatory hyperinflation of upper lobe.
 Radiographically seen as "hair-pin" turning of vessels &
"too-many nodules" along cardiac margin, which are end-on
vessels.

45. RLL Collapse

46. LUL Anatomy
On left there is no middle lobe; Anatomical equivalent region corresponding to
right middle lobe is the lingula, & like RML, is also composed of two
segments. Unlike their counterparts on the right however, the segments are
stacked one on top of another, rather than side. Note that upper lobe
pathology can appear very low on chest X-ray image. The upper lobe is
anterior lobe as much as it is upper lobe.

47. LUL Consolidation
Opacity left hemi-thorax
•Air-bronchogram lines
•Some loss of left heart
border.
Characteristically not a
dense opacity of the PA
view

48. Opacity Can be sharply
bordered by the oblique
fissure
•Does not involve the
diaphragm

49. LUL Collapse
 Left major fissure is displaced
ant, roughly parallel to ant
chest wall.
 On PA view it produces a
faint, hazy opacity in left upper
hemithorax, that can be
mistaken for pleural
thickening.

50. LUL Collapse
 Left cardiac contour is frequently obscured by lingula.
 Hyper-expanded left lower lobe occupies most of left
hemithorax, with its superior segment occupying apex,
mimicking an aerated upper lobe.
 Left hilar structures are retracted cephalad.

51. LUL Collapse

52. LUL Collapse
Luftsichel, an indirect sign of LUL collapse.
 Its Crescent of aerated lower lobe.
 This represent an incomplete major fissure pulled
forward by atelectatic upper lobe, interposed between
atelectasis & aortic arch.
 Left lower lobe basilar segmental arteries are elevated
and clearly visible in retrocardiac location.

53. Note the
increased
opacification of
left upper lung
field with
elevation of left
hemi-diaphragm.
In addition,
there is lucency
adjacent to the
aorta.
This is the
Luftsichel sign,
representing an
over-expanded
right lower
lobe.

55. LLL Anatomy
Left lower lobe is similar in structure to Right lower lobe except that it has two
segments combined - as the anterior and medial basal segments share a
common bronchial supply, these two segments are characteristically
combined, forming an anterior medial basal segment.

56. LLL Consolidation
• Look Behind the Heart Shadow
One of the more subtle appearances of
consolidation can be seen when the left heart
shadow appears abnormally dense.
•
Obliteration of the Descending Aorta
"The descending aorta indents the superior and
posterior basal segments of the LLL, and its lateral
margin is therefore obliterated by lesions in these
segments"

57. Appears as an area of increased
opacity within the LLL
•Some loss of the hemi-diaphragm
medially is seen
•increased density behind left
heart shadow

58. •Increased opacity within the
LLL
•Loss of the normal darkening
of the thoracic spine inferiorly
•some loss of the left hemi-diaphragm
posteriorly
May be sharply delineated by
oblique fissure

59. LLL Collapse
 Left major fissure can parallel left cardiac
border & the completely atelectatic lobe can
mimic a left paraspinal mass.
 Increased retrocardiac opacity with
obscuring of left lower lobe vessels & left
hemidiaphragm.
 Caudad displacement of left hilum.
 Mediastinal shift can lead to partial
obliteration of the aortic arch (the top of the
knob sign)

66. This image shows complete opacification of most of left upper lobe. When bronchi
remain aerated, they are seen as branching lucencies called air-bronchograms. This
image represents infectious pneumonia, limited by major fissure, resulting in a sharp
border.

67. Thank you