pneumocephalus
Pronunciation: new-moh-SEF-ah-lus
The presence of air within the intracranial space, typically occurring as a complication of neurosurgical procedures.
Full Definition
Pneumocephalus refers to the abnormal presence of air or gas within the intracranial compartment, which can occur in various locations including the subdural, subarachnoid, intraventricular, or intraparenchymal spaces. While small amounts of pneumocephalus are common and expected after cranial surgery, extensive pneumocephalus can cause increased intracranial pressure and neurological deterioration. The condition can result from skull base fractures, neurosurgical procedures, or rarely from infections with gas-producing organisms. Tension pneumocephalus is a neurosurgical emergency where trapped air creates a mass effect. On imaging, pneumocephalus appears as hypodense (dark) areas on CT scans and as signal voids on MRI.
Usage
Usage note: Distinguish between expected postoperative pneumocephalus and pathological tension pneumocephalus.
In Context
- "Postoperative CT revealed expected pneumocephalus without mass effect." — Radiological report
- "The patient developed tension pneumocephalus requiring immediate decompression." — Emergency department note