- Inflammation of middle ear spreads into mastoid air cells via the "aditus ad antrum"
- Complications include, but are not limited to: meningitis, encephalitis, venous sinus thrombosis, and brain abscesses.
- Vast majority of acute mastoiditis occurs as a result of, or simultaneous with, acute otitis media
- Mastoiditis is unlikely if middle ear examination is normal
Mastoiditis with subperiostal abscess
- Abnormal TM findings
- Abnormal mastoid findings
- Erythema, edema, tenderness
- Abnormal pinna findings
- Protrusion of auricle, obliteration of postauricular crease
- Cranial nerve VI and VII palsies
- Middle ear fluid cultures
- CT mastoid with IV contrast
- Delineates extent of bony involvement
- Helps to diagnosis abscess formation
Coverage against S. pneumoniae, S. pyogenes, S. aureus, H. influenzae