Chest x-ray: ABCDE (summary)

This is a basic article for medical students and other non-radiologists

Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review:

  • A: airways
  • B: breathing (the lungs and pleural spaces)
  • C: circulation (cardiomediastinal contour)
  • D: disability (bones - especially fractures)
  • E: everything else, e.g. pneumoperitoneum

Reference article

This is a summary article; we do not have a more in-depth reference article.

Summary

Airways

Start at the top in the midline and review the airways.

  • trace down the trachea to the carina
    • is it straight and midline?
    • is there any narrowing?
  • trace down both main bronchi
    • is the carina wide (more than 100 degrees)?
    • is there bronchial narrowing or cut-off?
    • is there any inhaled foreign body?

chest x-ray assessment of the airways

Breathing

Look for lung and pleural pathology.

  • both lungs should be well expanded and similar in volume
    • can you count 10 posterior ribs bilaterally?
    • is one lung larger than the other?
  • compare the apical, upper, middle and lower zones in turn
    • are they symmetrical?
    • are there areas of increased density?
  • trace the lung vessels
    • do they branch out progressively and uniformly?
    • can you see the retrocardiac and retrodiaphragmatic lung vessels?
    • are there extra lines in the periphery that aren't vessels?
  • trace the lateral margins of the lung to the costophrenic angles
    • are the costophrenic angles crisp?
  • trace the hemidiaphrams in to the vertebra
    • can you see the whole of the hemidiaphragm?
  • trace the cardiac borders
    • can you clearly see the left and right heart border?
    • can you see the descending aorta?

chest x-ray assessment of lungs and pleural spaces

Circulation

Look at the heart and vessels (systemic and pulmonary).

  • check the cardiac position
    • is 1/3 to the right and 2/3 to the left?
  • assess cardiac size
    • is the cardiothoracic ratio < 50%?
  • check the position and size of the aortic arch and pulmonary trunk
  • check the width of the upper mediastinum
  • look at the hilar vessels
    • can you see them clearly on both sides?
    • are they at a similar height?
    • can you see a preserved hilar point bilaterally? 

chest x-ray assessment of the cardiomediastinum

Disability

Check for any bony pathology (fracture or metastasis).

  • trace along each posterior (horizontal) rib on one side of the chest
    • is there a fracture or abnormal area?
  • repeat with the other side of the chest
  • now trace lateral and anterior ribs on the first side
  • repeat on the other side
  • now, check the clavicles and shoulders
    • can you trace around the cortex of the bones?
  • finally the check the vertebral bodies
    • are they all rectangular and of a similar height?
    • can you see 2 pedicles per vertebral body?
    • are there disc spaces?

chest x-ray assessment of the bony thorax

Everything else

Review the upper abdomen, soft tissues and take a look at some final check areas.

  • is there free gas under the diaphragms?
  • is there subcutaneous emphysema?
  • is the gastric bubble in the correct place?
  • is there a hiatus hernia?
  • is there an absent breast shadow?
  • are there any surgical clips?
  • check again...
    • are the lung apices clear?
    • is there any retrocardiac or retrodiaphragmatic pathology?

chest x-ray assessment of everything else

Medical student radiology curriculum