Deafness
Differential Diagnosis
Common Diagnoses
Occasional Diagnoses
- Ménière’s Disease
- Otosclerosis
- Noise Damage to Cochlea
- Barotrauma
- Viral Acoustic Neuritis
- Large Nasal Polyps or Nasopharyngeal Tumour
- Drugs: Streptomycin, Gentamicin, Aspirin Overdose
Rare Diagnoses
- Vascular (Haemorrhage, Thrombosis of Cochlear Vessels)
- Acoustic Neuroma
- Vitamin B12 Deficiency
- CNS Causes (e.g. Multiple Sclerosis, Cerebral Secondary Carcinoma)
- Cholesteatoma
- Paget’s Disease
- Traumatic (e.g. to Tympanic Membrane or Ossicles)
Ready Reckoner
Key distinguishing features of the most common diagnoses
Earwax | OM | OE | Glue Ear/ET | Presbyacusis | |
---|---|---|---|---|---|
Pain | Possible | Yes | Yes | No | No |
Pinna Traction Painful | No | No | Yes | No | No |
Discharge from EAM | Possible | Possible | Yes | No | No |
Conductive Deafness | Yes | Yes | Yes | Yes | No |
Fluid Level on Drum | No | No | No | Yes | No |
Possible Investigations
Likely:(In children) audiogram and tympanometry.
Possible:Ear swab.
Small Print:FBC/B12 levels, skull X-ray, further imaging.
- Audiometry quantifies loss and distinguishes sensorineural from conductive hearing loss.
- Tympanometry measures the compliance of the eardrum. Fluid in the middle ear flattens the compliance curve.
- Swab of ear discharge: Discharge can be swabbed to guide treatment in refractory otitis externa.
- FBC/B12 levels: To confirm B12 deficiency.
- Skull X-ray: For Paget’s disease.
- Further imaging: e.g. CT and MRI scans may be arranged by specialist for suspected acoustic neuroma, multiple sclerosis or cerebral pathology.
Top Tips
- Take parents seriously if they suspect their child is deaf. There may be no physical signs in glue ear, and tympanometry will yield the diagnosis.
- Warn patients with otitis media that hearing may take a few weeks to return completely to normal – this saves unnecessary attendances with patients complaining that ‘The antibiotics haven’t worked’.
- In a case with no immediately alarming features and no past history of significant ear disease, it is reasonable to defer a comprehensive history and examination – instead, take a quick look at the ear canals. If the diagnosis appears to be earwax, arrange syringing. Assess in more detail only if there is no earwax or syringing doesn’t solve the problem.
- Remember how to perform and interpret Rinne’s and Weber’s tests – these are invaluable in assessing the less straightforward cases.
Red Flags
- Remember the possibility of acoustic neuroma if there is progressive unilateral sensorineural deafness – especially if there is accompanying tinnitus, vertigo or neurological symptoms or signs.
- Otherwise unexplained and persistent serous otitis media in adults may be due to nasopharyngeal carcinoma – refer for urgent examination of the nasopharyngeal space.
- Sudden onset of profound sensorineural deafness is usually viral or vascular and requires same-day ENT assessment.
- Otosclerosis requires early diagnosis for effective treatment. Consider the diagnosis in otherwise unexplained conductive deafness in young adults, especially if there is a family history.