Intracranial epidural abscess

Intracranial epidural abscess, almost always a complication of frontal sinusitis, mastoiditis, or craniotomy, often remains unsuspected until angiography or surgery. Four cases arc presented which stress the roentgen features of intracranial epidural abscess. These findings include opacification of the frontal sinuses, osteomyelitis of the skull, and intracranial epidural gas. Cerebral angiography provides a definitive diagnosis when an epidural avascular area is demonstrated in the appropriate setting. Once the diagnosis is established, epidural abscess constitutes a neurosurgical emergency.