subdural empyema; subdural abscess

Etiology

• predisposing conditions
  • otorhinolic infections
    • sinusitis, otitis media, mastoiditis

Epidemiology

• accounts for 15-20% of all localized intracranal infections

Pathology

• increased intracranial pressure
• meningeal irritation (meningitis)
• focal cortical inflammation (encephalitis)

Radiology

• magnetic resonance imaging (MRI)
  • preferable to computed tomography (CT)
  • differentiates empyema from sterile effusions & subdural hematoma

Complications

• mortality 10-20%
• metastatic infection 5%

Differential diagnosis

• subdural hematoma
• sterile subdural effusion
• brain abscess
• epidural abscess

Management

• neurosurgical emergency
  • craniotomy allows wide exposure & adequate drainage
  • decompression of the brain
  • evacuation of empyema
• empiric antibiotic therapy (triple antibiotics)
  • vancomycin +
  • metronidazole +
  • cefepime, ceftazidime, or meropenem

More general terms

• empyema
• central nervous system (CNS) infection

Additional terms

• brain abscess
• epidural abscess
• subdural space