Sinusitis is a common infection that affects children each year. On average, children will experience 5 to 8 viral upper respiratory infections per year, of which 5% to 13% may be complicated by a secondary bacterial infection of the paranasal sinuses. When a sinus infection goes unrecognized or untreated, complications may result. Complications of sinusitis include preseptal, periorbital cellulitis; orbital cellulitis; subperiosteal abscess; and intracranial complications.

Intracranial complications of sinusitis in order of frequency are epidural abscess, subdural empyema, meningitis, encephalitis, intracerebral brain abscess, dural sinus thrombophlebitis, and middle cerebral artery ischemia. Intracranial complications can arise from the spread of septic thrombi or emboli from the sinus via the valveless diploic veins of the skull base that penetrate the dura, osteomyelitis of the sinus wall that extends posteriorly, or an infection that penetrates an existing bony defect in the sinus cavity.

Clinicians should suspect intracranial complications of sinusitis in any children with sinusitis and any neurologic finding, other signs of complicated sinusitis, persistent headache, persistent fever, or nausea/vomiting after antibiotic therapy.