Air bubble sign (tension pneumocephalus)

The air bubble sign is seen on CT of the brain and represents multiple small foci of air within the subarachnoid space, especially the Sylvian fissure.1

Although described as a sign of tension pneumocephalus it is also seen in pneumocephalus without elevated pressures.2


It should not be confused with the similarly named sign of complicated pulmonary hydatid disease: see air bubble sign (pulmonary hydatid).

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Article information

rID: 62434
Section: Signs
Synonyms or Alternate Spellings:

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Cases and figures

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    Tension pneumocranium post FESS - perforation of ethmoidal air cells
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