1. Lobar Collapse

2. Lung Anatomy (1) aortic arch (2) pulmonary trunk
(3) left atrial appendage
(4) left ventricle
(5) right atrium
(6) superior vena cava
(7 & 8) diaphragm
(9) transverse fissure
Transverse fissure – 6th rib laterally
Does not estend beyond pulm artery medially
Visible in 50%

3. Lung Anatomy (1) oblique fissure (2) transverse fissure
(3) retrocardiac space
(4) retrosternal space
Oblique fissure from t4 posteriorly
Propeller shaped
Differentiation between sides- left is more vertical, has more posterior junction with the diaphragm= does not intersect transverse fissure
Left diaphragm is lower and possesses stomach bubble by 2.5cm in 94% population

4. Lobar Extent T4 – upper portion faces forwards amd laterally
Lower portion faces posteriorly and laterally

5. Lobar Extent

6. Silhouette Sign
If two soft tissue densities lie in apposition, then they will not be visible separately
If they are separated by air, the boundaries of both will be seen

7. Uses of Silhouette Localisation without a lateral view
Loss of clarity of a structure suggests there is adjacent soft tissue shadowing even when the abnormality itself is not clearly visualised. This is particularly valuable in some cases of lobar collapse.

8. Lobar Collapse Partial or complete loss of lung volume Air resorption
Atelectasis

9. Common causes of lobar collapse
Proximal stenosing bronchogenic carcinoma.
Middle aged or elderly, almost always smokers.
Asthma due to mucous plugging
Young adult or older child ,responds to physiotherapy.
Inhaled foreign body
Infants , such as a peanut.
Retention of secretions
Any age, frequent cause of post operative collapse.
Ventilation
Endotracheal tube is inserted too far, entering one main bronchus and occluding the other.

10. Signs of Lobar Collapse
Shift of fissures
Crowding of vessels (increased opacity)
Extra lobar
Hemi diaphragm elevation
Mediastinal shift towards side of collapse
Hilar shift and distortion
Compensatory hyperinflation
Rib approximation
Shift of other structures e.g. granuloma

11. Right upper lobe collapse
Minor fissure pivots and bows
Right hilar elevation
May simulate mediastinal widening
Deviation of trachea
Both fissures concave superiorly

12. Right upper lobe collapse

13. Golden’s S sign

14. Golden’s S sign

15. Right Lower lobe collapse
Posterior and medial collapse
Obliteration of the right hemi diaphragm
Heart border clearly seen
Transverse fissure pulled inferiorly

16. Right Lower lobe collapse

17. Right Middle Lobe Collapse
Right horizontal and oblique fissure move towards each other
often subtle
blur the normally sharp right-heart border (silhouette sign)

18. Right Middle lobe Collapse

19. Left lower lobe collapse
Posterior and medial collapse
triangular opacity – sail sign
hemidiaphragm may be obscured

20. Left Lower lobe collapse

21. Left Upper Lobe Collapse
veil like opacity
aortic knuckle, left hilum, and left-heart border initially ill defined but may progress to become sharp
almost vertical oblique fissure

22. Left Upper Lobe Collapse

23. Left Upper Lobe Collapse ‘Luftsichel’

24. Complete Collapse

25. Summary Right
Right Upper lobe
Right middle lobe
Right Lower Lobe

26. Summary Left
Left upper lobe
Left lower lobe