Overview

As a general rule of thumb, problems in the outer and middle ear cause conductive hearing loss, and problems in the inner ear cause sensorineural hearing loss.

Causes

Conductive hearing loss

Sensorineural hearing loss

History Taking

Overview

With each symptom, always (if relevant) ask about:

  • When did it start?
  • Did it come on suddenly or gradually?
  • Is it continuous or intermittent?
  • Has this ever happened before?
  • Is this in one or both ears?

Hearing loss

  • Site:
    • Unilateral or bilateral?
  • Onset:
    • Gradual or sudden
  • Character:
    • What sounds do they have difficulty hearing?
    • High-pitched or low-pitched sounds?
    • What volumes of sound are affected? How quiet is their limit of hearing?
  • Timeline:
    • Is it continuous or intermittent?
  • Severity:
    • Has anyone else noticed it?
    • Does anyone tell the patient they speak too loudly?
    • Does the patient have to ask people to repeat themselves?
    • Does this affect their work or social life?

External ear

  • Has there been any trauma to the ear?
  • Has anything been put into the ear?

Middle ear

  • Any ear discharge?
  • Is it blood, purulent, or clear?
  • Any ear “popping”?

Inner ear

  • Is there tinnitus? – is there any ringing or humming?
  • Is there any vertigo? – are they dizzy? Is the room spinning?

Systems Review

Screen for red flags:

  • Any fever?
  • Any night sweats?
  • Any unexplained weight loss?
  • Any symptoms associated with a stroke? Examples are:
    • Problems with balance?
    • Problems with speech?
    • Weakness or numbness?

Screen for ear symptoms:

  • Tinnitus?
  • Dizziness? – does the room spin?
  • Ear pains?
    • Use SOCRATES
  • Ear discharge?
  • Do they hear any clicking or popping?
  • Do their ears ever feel full?
  • Has anything been inserted into the ear?

Screen for nose symptoms:

Screen for throat symptoms:

Screen for neurological symptoms:

Past Medical History

Questions include:

  • Do they have any other medical conditions?
  • Have they ever had any previous surgery?
  • Do they take any regular medications?
  • Do they take any over-the-counter medications, herbal remedies, or supplements?
  • Have they had a recent infection such as a cold or the flu?
  • Do they take eardrops? – some patients forget these count as regular medications

Family History

  • Is there any family history of anything similar?

Allergy History

  • Are they allergic to anything?
    • What happens during the allergic reaction?

Social History

  • Do they smoke?
    • If so, how much and how long?
  • Do they drink alcohol?
    • If so, how much and how long?
  • Do they use any illicit drugs?
    • If so, how much and how long?
  • What is their occupation?
  • Who’s at home?
    • What support do they have?
  • How has this impacted their activities of daily living?
  • Has there been any recent foreign travel?

Physical Examinations

Overview

An ear examination and cranial nerve exam should be performed, including using Weber and Rinne tuning fork tests. Some signs that may be present include:

  • Otoscopy may show:
  • Impacted earwax
    • External ear canal erythema and/or swelling
    • Cholesteatoma
    • Problems with the tympanic membrane (e.g. erythema, perforation, or effusion)
  • Arterial bruits (e.g. carotid bruit) which may suggest a cause of objective tinnitus
  • Weber and Rinne tests may help with identifying the type of any hearing loss present
  • A vestibular schwannoma may lead to cranial nerve involvement:
    • Vestibulocochlear nerve (CN VIII) – hearing loss, tinnitus, and vertigo
    • Trigeminal nerve (CN V) – absent corneal reflex, facial numbness
    • Facial nerve (CN VII) – facial nerve palsy

Investigations

  • Audiometry:
    • Identifies any associated hearing loss
  • MRI of the cerebellopontine angle:
    • May be considered for vestibular schwannoma

Differential Diagnoses: Mainly Conductive Hearing Loss

Impacted earwax

  • A history may reveal:
    • The use of cotton buds in the ear or hearing aids
  • A physical exam may reveal:
    • Otoscopy usually identifies impacted earwax
  • Diagnosis is clinical

Otitis externa

  • A history may reveal:
    • Ear pain, ear itching, and ear discharge
    • Recent swimming
  • A physical exam may reveal:
    • An erythematous/swollen/eczematous canal
    • Otorrhoea may be present
  • Diagnosis is clinical

Otitis media

  • A history may reveal:
    • More common in children
    • Associated earache and fever
    • May perforate leading to foul discharge release from the ear 
  • A physical exam may reveal:
    • A red, bulging, tympanic membrane
  • Diagnosis is clinical

Otitis media with effusion (glue ear)

  • A history may reveal:
    • More common in younger children
    • Hearing loss and problems with speech and language development, or sudden decrease in school performance
    • A previous history of acute otitis media
  • A physical exam may reveal:
    • Otoscopy may show: loss of the right reflex, yellow/amber/blue tympanic membrane, air bubbles or an air-fluid level behind the tympanic membrane, retracted tympanic membrane
  • Diagnosis is clinical

Otosclerosis

  • A history may reveal:
    • Hearing loss in a relatively young patient (~20s)
    • There may be associated tinnitus
    • Most commonly bilateral but can be unilateral
    • There is usually a family history
  • A physical exam may reveal:
    • Weber and Rinne’s tests show conductive hearing loss
  • Investigations may reveal:
    • Audiometry – conductive hearing loss

Cholesteatoma

  • A history may reveal:
    • Foul-smelling persistent discharge
    • There may be associated tinnitus and ear pain
  • A physical exam may reveal:
    • Crusting/pus/debris in the attic (upper part of the middle ear) on otoscopy
  • Investigations may reveal:
    • Pure tone audiogram – shows conductive hearing loss
    • CT petrous temporal bone – confirms the diagnosis
    • MRI – considered if soft tissue involvement suspected

Differential Diagnoses: Mainly Sensorineural Hearing Loss

Presbycusis

  • A history may reveal:
    • More common in older patients (>50 years)
    • Slow, gradual, high-frequency bilateral hearing loss that is worse in louder environments
    • Difficulty with understanding consonants such as ch, f, k, p, and s, and this makes understanding speech difficult
  • A physical exam may reveal:
    • Weber and Rinne’s tests show sensorineural hearing loss
  • Investigations may reveal:
    • Audiometry – bilateral high-frequency sensorineural hearing loss

Noise-induced hearing loss

  • A history may reveal:
    • A history of working in loud environments or using loud tools
    • There may be associated tinnitus
  • Investigations may reveal:
    • Pure tone audiometry – shows sensorineural hearing loss

Ménière’s disease

  • A history may reveal:
    • 15-minute to 24-hour episodes of vertigo, tinnitus, hearing loss, and aural fullness
    • Aural fullness may precede the attack
  • Investigations may reveal:
    • Diagnosis is clinical
    • Audiometry – unilateral sensorineural hearing loss

Vestibular schwannoma (acoustic neuroma)

  • A history may reveal:
    • Hearing loss, tinnitus, vertigo
    • Cranial nerve involvement (e.g. the trigeminal nerve and facial numbness)
    • May present with sudden sensorineural hearing loss (<72 hours)
  • A physical exam may reveal:
    • Signs of trigeminal nerve (CN V) or facial nerve (CN VII) palsy
  • Investigations may reveal:
    • MRI of the cerebellopontine angle – investigation of choice
    • Audiometry – helps determine the degree of hearing loss

Labyrinthitis

  • A history may reveal:
    • Acute vertigo that is worsened by movement, nausea, and vomiting
    • There may be associated tinnitus
    • A history of a recent upper respiratory tract infection
  • Diagnosis is mainly clinical

Stroke

  • A history may reveal:
    • Risk factors for atherosclerotic disease, such as hypertension, hyperlipidaemia, ischaemic heart disease
    • FAST symptoms: facial drooping, arm weakness, slurred speech, word-finding difficulties, ataxia, and vertigo
  • A physical exam may reveal:
    • Hemiparesis, hemisensory losses, aphasia, ataxia, nystagmus
  • Investigations may reveal:

Alport’s syndrome

  • A history may reveal:
  • Investigations may reveal:
    • Pure tone audiometry – shows sensorineural hearing loss
    • Urinalysis – shows microscopic haematuria
    • Renal biopsy – shows loss of staining of type IV collagen
    • Molecular genetic testing – may confirm the diagnosis

Idiopathic sudden sensorineural hearing loss

  • A history may reveal:
    • < 72-hour history of sudden sensorineural hearing loss
    • There may be associated tinnitus and vertigo
  • Investigations may reveal:
    • MRI of the cerebellopontine angle – normal, performed to screen for vestibular schwannoma

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