This document discusses imaging of the chest in trauma patients. It describes the use of chest radiographs and CT scans to evaluate for fractures, dislocations, pneumothoraces, hemothoraces, pulmonary contusions and lacerations, diaphragm injuries, and vascular injuries following chest trauma. Key findings on imaging include rib fractures indicating underlying organ injury, flail chest, scapula fractures requiring CT, pneumothorax appearance varying with patient position, and indirect signs of aortic injury on CT such as mediastinal hematoma.

1. Imaging the chest in traumaImaging the chest in trauma

2. Chest traumaChest trauma
Blunt
Penetrating

3. Trauma Chest RadiographTrauma Chest Radiograph
Usually AP,
often supine,
frequently in
poor
inspiration.

4. CT ChestCT Chest

5. Fractures and DislocationsFractures and Dislocations
Spine
Ribs
Clavicles
Sternum
Shoulders

6. Spine InjuriesSpine Injuries
Loss of alignment,
fractures and
paraspinal hematoma.

7. Rib FracturesRib Fractures
Indicator of underlying
pleura, lung, liver,
spleen, kidney injuries.

8. Flail ChestFlail Chest
Multiple rib fractures,
especially if individual
ribs fractured more
than once, may cause
paradoxical motion.
Associated pulmonary
contusion.

9. Clavicle InjuriesClavicle Injuries

10. Sterno-clavicle joint dislocationSterno-clavicle joint dislocation

11. Sterno-clavicle dislocation: CTSterno-clavicle dislocation: CT

12. Shoulder InjuriesShoulder Injuries
dislocations and
scapula fractures

13. CT Needed if Scapula Fracture SeenCT Needed if Scapula Fracture Seen

14. AIR where it shouldnAIR where it shouldn’’t bet be
Pneumothorax
Pneumomediastinum
Subcutaneous emphysema
Systemic venous air embolism
Pneumopericardium
Pneumoperitoneum/retroperitoneum

15. pnxpnx

16. PNEUMOTHORAX: CTPNEUMOTHORAX: CT
Much more sensitive
Even a small traumatic pneumothorax is
important, especially if patient
mechanically ventilated or going to OR:
A simple pneumothorax can be
converted into a life- threatening tension
pneumothorax.

17. PNEUMOTHORAX: CTPNEUMOTHORAX: CT

18. Pneumothorax: SimplePneumothorax: Simple
Erect AP/PA view best
Visceral pleural line
No vessels or markings
Variable degree of lung collapse
No shift

19. PNEUMOTHORAX: SimplePNEUMOTHORAX: Simple

20. PNEUMOTHORAX: TensionPNEUMOTHORAX: Tension
Erect AP/PA view best
Shift of mediastinum/heart/trachea away
from PTX side
Depressed hemidiaphragm
Degree of lung collapse is variable

21. PNEUMOTHORAX: TensionPNEUMOTHORAX: Tension

22. PNEUMOTHORAX: SupinePNEUMOTHORAX: Supine
Supine AP view has limited sensitivity: 50%
Deep sulcus sign
Too sharp heart border/hemidiaphragm sign
Increased lucency over lower chest
Cant see vessels

26. PNEUMOTHORAX: OpenPNEUMOTHORAX: Open
- Gunshot or other wound (hole > 2/3 tracheal diameter) +/-
exit wound
- Air enters the wound rather than trachea and leads to
hypoxia.
- Unequal breath sounds

27. PNEUMOMEDIASTIUMPNEUMOMEDIASTIUM
Usually from ruptured alveoli.
Can also be from trachea, bronchi,
esophagus, bowel and neck injuries.

28. Air forms linear / curvilinear lucencies outlining mediastinal
contours :
Air anterior to pericardium: pneumopericardium
Air around pulmonary artery and main branches: ring around
artery sign
Air outlining major aortic branches: tubular artery sign
Air outlining bronchial wall: double bronchial wall sign
Continuous diaphragm sign: due to air trapped posterior to
pericardium
V sign of Naclerios: “V” sign at aortic-diaphragm junction
Paediatric pneumomediastinum: may have slightly different
appearances:
elevated thymus: thymic wing sign
air crossing the superior mediastinum: haystack sign

29. Ring around the artery signRing around the artery sign

31. V sign of nacleriosV sign of naclerios

32. PneumopericardiumPneumopericardium

33. Spinnaker / angel wing signSpinnaker / angel wing sign

34. Haystack signHaystack sign
air around heart makes it look like a Monet paintingair around heart makes it look like a Monet painting

35. PNEUMOMEDIASTINUM: CTPNEUMOMEDIASTINUM: CT

36. Tracheal / bronchial tearsTracheal / bronchial tears
• Most common site - near the carina, because the airway is fixed
and subject to shear injury.
• Tears within the mediastinal pleura – pneumomediastinum
• Tears beyond the mediastinal pleura - pneumothorax.
• Left main bronchus : has a longer mediastinal course than the
right main bronchus & so injury - more likely to cause a
pneumomediastinum & vice versa.
• Severe injuries, both a pneumomediastinum and a
pneumothorax may be present.

37. Fallen Lung signFallen Lung sign
With complete laceration of the main bronchus, the bronchus may become partially
or completely detached, allowing the lung to fall into a dependent lateral position

38. PneumoperitoneumPneumoperitoneum
.

39. PneumoretroperitoneumPneumoretroperitoneum

40. HEMOTHORAXHEMOTHORAX
Venous or arterial bleeding
Can miss hundreds of cc’s on supine film

41. HEMOTHORAXHEMOTHORAX

44. CT: HEMOTHORAXCT: HEMOTHORAX
35-70 HU

46. PULMONARY CONTUSION andPULMONARY CONTUSION and
LACERATIONLACERATION
Contusion: Blood in intact lung
parenchyma. Non-penetrating.
Laceration: Blood in torn lung
parenchyma
Can’t tell difference on chest film.
Contusions peak in 2-3 days, begin to
resolve in a week; lacerations take much
longer to resolve and may leave scars

47. ContusionContusion
• Manifest at the time of the initial examination
• Little tendency to increase in severity with subsequent
examinations.
• Radiographic clearing within 48 hours.
• Features are often not localised in a lobar or segmental
pattern.
Plain film Not sensitive.
• Faint patchy consolidative following history of blunt trauma.
• CT – focal, non segmental parenchymal opacification.
• Can have sub-pleural sparing with smaller contusions
• Commoner posteriorly and in lower lobes.

49. LacerationsLacerations
• Almost always have concurrent contusion
• Pathology
Classification:
Type I - compression rupture: most common type of laceration that usually occurs
as a 2-8 cm lesion in the central lung
Type II - compression shear: occurs after sudden compression of the lower chest
when the lung suffers from a shear injury to the spine
Type III - direct puncture / rib penetration: occur with a penetrating fractured rib;
these lesions are commonly multiple
Type IV - adhesion tears: occurs in sudden injuries of the chest wall where prior
pleuropulmonary adhesions had been created

50. •Pattern can be similar to contusion
•Often have added rib fractures & pneumothorax
CT
•Regions of pulmonary contusion with added blebs
(pneumatoceles) with air fluid levels.
•Due to normal pulmonary elastic recoil, lung tissues
surrounding a laceration often pull back from the laceration
which manifesting at CT as a round or oval cavity, instead of
having the linear appearance in other solid organs.
•Severe laceration have gross disruption of lung parenchymal
architecture.

52. DIAPHRAGM InjuriesDIAPHRAGM Injuries
5% of major blunt
trauma, also thoraco-
abdominal
penetrating trauma
Left clinically injured
more than right
60/40
Sensitivity of Chest
film 40%. CT better,
but still misses some
Hard signs: NGT
through g.e. junction
then up into chest,
and hollow viscus
above diaphragm
Soft signs: Indistinct
diaphragm, effusion,
atelectasis

53. Position of NG TubePosition of NG Tube

54. Gut in ChestGut in Chest

57. Vascular InjuryVascular Injury
Signs of mediastinal haematoma:
widened mediastinum
indistinct or abnormal aortic contour
deviation of trachea or NGT to the right
depression of left main bronchus
widened paraspinal stripe

59. CTCT
Indirect signs of aortic injury:
mediastinal haematoma
periaortic fat stranding
CTA : sensitivity 100%; specificity 100%.
Signs of mediastinal haematoma:
abnormal soft tissue density around mediastinal structures
Location – periaortic haematoma than isolated mediastinal
haematoma remote from the aorta.
Signs of aortic injury:
intraluminal filling defect (intimal flap or clot)
abnormal aortic contour (mural haematoma)
Pseudoaneurysm & extravasation of contrast