As of the latest update, Google Chrome and Microsoft Edge have made a breaking change to how file uploads are handled. Once your system installs this update, you will not be able to upload new images. Please use another browser until we can get it fixed.

Air-space opacification (summary)

Dr Jeremy Jones et al.
This is a basic article for medical students and other non-radiologists

Air-space opacification is a descriptive term that refers to filling of the lung parenchyma with material that attenuates x-rays more than the unaffected surrounding lung tissue. It is the radiological correlate of the pathological diagnosis of pulmonary consolidation.

Reference article

This is a summary article; read more in our article on air-space opacification.

  • anatomy
  • pathophysiology
    • material fills the lung parenchyma
      • fluid: pulmonary edema 
      • pus: pneumonia
      • blood: pulmonary hemorrhage
      • cells: cancer
      • protein: alveolar proteinosis (rare)
    • distribution
      • patchy
        • air-space filling is incomplete and non-contiguous
        • residual gas within the alveoli
      • lobar
        • complete filling of a lobe of the lung
        • clear delineation between consolidation and adjacent gas-filled structures
          • the remainder of the lung or in bronchi traveling through the lobe
        • no margin between consolidation and other soft-tissue density structures
          • mediastinum or diaphragm
      • multifocal
        • symmetrical or asymmetrical
        • perihilar or peripheral
        • often non-specific without clinical history and examination findings
  • role of imaging
    • confirm air-space opacification and differentiate from atelectasis or pleural effusion where possible
    • help to determine the cause, e.g. other signs of heart failure
    • identify complications, e.g. abscess formation
    • demonstrate accompanying pathology, e.g. effusion or empyema
    • determine severity and extent, e.g. number of lobes involved, uni- or bilaterality
  • common pathology
  • normal air-filled lung is black
  • air-space opacification is radiopaque (white)
  • aerated bronchi
  • air-space opacification looks very similar to the chest x-ray
    • distribution can be assessed more accurately
    • assessment of complications is more accurate
Medical student radiology curriculum
Share article

Article information

rID: 31402
System: Chest
Synonyms or Alternate Spellings:
  • Airspace opacification (summary)

Support Radiopaedia and see fewer ads

Cases and figures

  • Case 1: Left lower lobe consolidation
    Drag here to reorder.
  • Case 2: Left lower lobe consolidation
    Drag here to reorder.
  • Case 3: Right upper lobe consolidation
    Drag here to reorder.
  • Right hemithorax ...
    Case 4: Right sided consolidation (multi-lobar)
    Drag here to reorder.
  • Case 6: right upper lobe consolidation
    Drag here to reorder.
  • Updating… Please wait.

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

     Thank you for updating your details.