Central skull base osteomyelitis in patients without otitis externa: imaging findings

Area of Science:

• Neurology
• Infectious Diseases
• Radiology

Background:

• Skull base osteomyelitis typically affects older diabetic patients with ear infections and Pseudomonas aeruginosa.
• Atypical central skull base osteomyelitis, originating from sphenoid or occipital bones without external otitis, is less common and may initially present only with headache.

Observation:

• This study reviewed six patients with central skull base osteomyelitis, none of whom had external otitis or temporal bone osteomyelitis.
• All patients presented with headache, cranial nerve deficits, and elevated erythrocyte sedimentation rate (in five of six).

Findings:

• Diagnosis was often delayed until Magnetic Resonance (MR) imaging revealed central skull base abnormalities.
• Key MR imaging findings included clival bone marrow T1 hypointensity and preclival soft tissue infiltration.
• Tissue sampling confirmed the diagnosis in all cases.

Implications:

• Central skull base osteomyelitis should be suspected in patients with headache, cranial neuropathy, elevated erythrocyte sedimentation rate, and abnormal clival imaging.
• Early diagnosis through tissue sampling and appropriate treatment can prevent intracranial extension, empyema, or death.