Chronic suppurative otitis media (CSOM) Flashcards
What are the complications of otitis media (not just CSOM)?
ntracranial
- Meningitis
- Extradural/intracranial abscess
- Sigmoid sinus thrombosis (because sigmoid sinus is near the mastoid)
Extracranial (more superficial infx): intratemporal VS extratemporal
Intratemporal cx (2’ bone erosion/thrombophlebitis of communicating vessels)
- TM perforation
- Tympanosclerosis (thickening of TM)
- Petrositis (involvement of petrous bone; note that CN V and VI may be affected)
- If infection spreads to the petrous apex (more medial), can cause Gradenigo syndrome [triad of retro/peri-orbital pain (CN5 involvement) + diplopia (CN6 palsy) + otorrhoea]
- Facial nerve palsy (CN7 palsy)
- Labyrinthitis (CN8): Represents spread of middle ear infection to inner ear
- Labyrinthine fistula -> note that fistulas are complications of a chronic process (CSOM) and not an acute process -> when a perforation epithelializes, it becomes a fistula which does not heal
Extratemporal cx
- Mastoiditis +/- mastoid sub-peri
What is the definition of CSOM?
Chronic inflammation (> 6 wks) of the middle ear a/w non-healing TM perf;
What is the pathophysiology of CSOM?
- Usually in children due to prolonged/recurrent AOM that is inadequately treated -> TM perf epithelializes and becomes a non-healing fistula forever
- May be iatrogenic from myringotomy or grommet tube insertion
- Fistula where tract is lined by mucosal epithelium (from middle ear) – prevents tract closure
What is central CSOM?
360 deg remnant eardrum surrounding it
What is marginal CSOM?
on margins, don’t have 360 deg remnant eardrum
What are the clinical features of CSOM?
Otorrhoea: intermittent, watery-mucoid/mucopurulent (if a/w infection)
CHL
- Mild (10-20dB) if only TM is damaged
- Severe (50-70dB) if ossicular chain is damaged (usually the incus)
Hard to differentiate AOM w/ perforation from CSOM on otoscopy -> Hx impt (especially duration, hx is the only distinguishing point)
Otoscope: can present a thickened TM due to fibrosis and inflammation -> resulting in a featureless TM (lacking bony structures and translucency)
What are the investigations of CSOM?
- Definitive diagnosis on otoscopy
- Consider PTA, tympanometry, swabs, vestibular assessment w/ fistula test, CT of temporal bones (aid surgical management), MRI (to delineate intra-cranial complications)
What is the management of CSOM?
Medical
- Regular aural toilet (drain pus – can be painful); keep ear dry (KED) to settle active infx
- If infected, give topical abx since TM has perforated and topical antibiotic can reach site of infection).
- Drugs tend to enter the inner ear via the oval window (where the footplate of the stapes lies)
Surgical i.e. tympanoplasty/myringoplasty (definitive treatment)
- Indications for sx: recurrent infection (absolute indication),. improve QOL/not keen on water precautions (e.g. in water sports athletes where it is difficult to KED without intact TM)
What are the complications of otitis media (not just CSOM)?
Intracranial
- Meningitis
- Extradural/intracranial abscess
- Sigmoid sinus thrombosis (because sigmoid sinus is near the mastoid)
Extracranial (more superficial infx): intratemporal VS extratemporal
Intratemporal cx (2’ bone erosion/thrombophlebitis of communicating vessels)
- TM perforation
- Tympanosclerosis (thickening of TM)
- Petrositis (involvement of petrous bone; note that CN V and VI may be affected)
- If infection spreads to the petrous apex (more medial), can cause Gradenigo syndrome [triad of retro/peri-orbital pain (CN5 involvement) + diplopia (CN6 palsy) + otorrhoea]
- Facial nerve palsy (CN7 palsy)
- Labyrinthitis (CN8): Represents spread of middle ear infection to inner ear
- Labyrinthine fistula -> note that fistulas are complications of a chronic process (CSOM) and not an acute process -> when a perforation epithelializes, it becomes a fistula which does not heal
Extratemporal cx
- Mastoiditis +/- mastoid sub-peri
