Abstract
Postoperative (or postprocedural) pneumocephalus is unique from those associated with
head injury, spontaneous cerebrospinal fluid leaks, and intracranial infection. Postoperative
cranial imaging usually demonstrates a small volume of air that remains in the surgical
bed, which is essentially self-limited and resolves over several weeks or less. However,
occasionally, surgical defects lead to symptomatic postoperative air entrapment, and
severe cases are generally due to one-way valves created by tissue, a mechanism shared
with severe traumatic pneumocephalus. In the case where this causes progressive pressurization,
this is termed tension pneumocephalus, analogous to its pulmonary counterpart. In
the closed adult cranium, the Monroe-Kellie doctrine can be extended to include pneumocephalus
if the compressible nature of gas is accounted for. Three illustrative cases are used
to highlight common etiologies of postoperative tension pneumocephalus, management
strategies, and imaging findings of these collections.
Keywords
pneumocephalus - nitrous oxide - postoperative complications - craniocerebral trauma
- skull - cerebrospinal fluid leak
