Air-space opacification (summary)

Dr Henry Knipe and Dr Jeremy Jones et al.

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

Reference article

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


  • pathophysiology
    • material fills the lung parenchyma
      • fluid: pulmonary oedema 
      • pus: pneumonia
      • blood: pulmonary haemorrhage
      • cells: cancer
      • protein: alveolar proteinosis (rare)
    • distribution
      • patchy
        • airspace 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 travelling through the lobe
        • no margin between consolidation and other soft-tissue density structures
          • mediastinum or diaphragm
      • multi-focal
        • symmetrical or asymmetrical
        • peri-hilar or peripheral
        • often non-specific without clinical history and examination findings
  • radiographic features
    • chest x-ray
      • confirmation of consolidation and additional findings
        • airspace opacification is radio-opaque (white)
        • normal air-filled lung is black
        • distribution may help with diagnosis
      • assessment of:
        • complications, e.g. abscess formation
        • accompanying pathology, e.g. effusion
        • severity, e.g. number of lobes involved
    • CT chest
      • air space opacification looks very similar to the chest x-ray
      • distribution can be assessed more accurately
      • assessment of complications is more accurate
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Article information

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

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Cases and figures

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    Case 1: Left lower lobe consolidation
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    Case 2: Left lower lobe consolidation
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    RUL consolidation
    Case 3: Right upper lobe consolidation
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    Right hemithorax ...
    Case 4: Right sided consolidation (multi-lobar)
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    Case 6: right upper lobe consolidation
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