Lobar collapse (summary)

Dr Jeremy Jones et al.

Lobar collapse is relatively common and occurs following obstruction of a bronchus. Gas is resorbed from the lung parenchyma distal to the obstruction resulting in the collapse of the lung, volume reduction and negative mass effect.

Reference article

This is a summary article; read more in our article on lobar collapse.

  • epidemiology
    • broad and dependent on the underlying cause
      • young children - foreign body
      • adolescent - asthma
      • elderly patient - cancer
  • presentation
    • dependent on the underlying cause
      • acute presentations will likely result in breathlessness
      • more chronic collapse may not result in symptoms
        • symptoms may relate to the underlying cause, e.g. weight loss and cough
  • pathophysiology
    • collapse occurs when the bronchus is obstructed
      • distal gas is absorbed
      • volume of the lung decreases
      • if all gas is absorbed and obstruction is complete a tiny wedge of pulmonary parenchyma remains
    • causes
  • investigation
    • chest x-ray
      • confirms collapse
    • blood work for infection or possible cancer
    • CT chest with contrast
      • assess an obstructing cancer
    • rigid bronchoscopy to remove a foreign body
    • flexible bronchoscopy for suspected cancer to allow biopsy
  • treatment
    • dependent on the cause of the collapse
      • foreign body should be removed
      • mucus may respond to chest physio

The most striking feature of lobar collapse (the collapse of an entire lobe) is the change in density of the tissue and associated volume loss. Change in density from lucent (black and gas-filled) to attenuating (white) is not specific for collapse, but in concert with volume loss, gives the diagnosis.

The diagnosis of lobar collapse requires knowledge of:

  • lobar anatomy (how many lobes and where are they)
  • chest x-ray anatomy (what each lobe sits against), and
  • knowledge about the silhouette sign (loss of gas in part of the lung will result in loss of distinction between the lung and surrounding tissue)

Medical student radiology curriculum
Share article

Article Information

rID: 30465
System: Chest
Synonyms or Alternate Spellings:

Support Radiopaedia and see fewer ads

Cases and Figures

  • Drag
    Mucous plug left ...
    Case 1: left lung collapse (mucus plug)
    Drag here to reorder.
  • Drag
    Case: right upper lobe collapse
    Drag here to reorder.
  • Drag
    Left upper lobe c...
    Case 3: left upper lobe collapse
    Drag here to reorder.
  • Drag
    Case 4: left lower lobe collapse
    Drag here to reorder.
  • Drag
    Case 5: left lower lobe collapse (peanut)
    Drag here to reorder.
  • Drag
    Case 6a: left upper lobe collapse (cancer)
    Drag here to reorder.
  • Drag
    Case 6b: left upper lobe collapse (cancer)
    Drag here to reorder.
  • Updating… Please wait.
    Loadinganimation

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.