Hearing | Notion

Rinne's and Weber's test

Performing both Rinne's and Weber's test allows differentiation of conductive and sensorineural deafness.

Rinne's test

tuning fork is placed over the mastoid process until the sound is no longer heard, followed by repositioning just over external acoustic meatus
'positive test': air conduction (AC) is normally better than bone conduction (BC)
'negative test': if BC > AC then conductive deafness

Weber's test

tuning fork is placed in the middle of the forehead equidistant from the patient's ears
the patient is then asked which side is loudest
in unilateral sensorineural deafness, sound is localised to the unaffected side
in unilateral conductive deafness, sound is localised to the affected side

Interpretation of Rinne and Weber tests

	Rinne result	Weber result
Normal	Air conduction > bone conduction bilaterally	Midline
Conductive hearing loss	Bone conduction > air conduction in affected ear
Air conduction > bone conduction in unaffected ear	Lateralises to affected ear
Sensorineural hearing loss	Air conduction > bone conduction bilaterally	Lateralises to unaffected ear

Deafness

The most common causes of hearing loss are ear wax, otitis media and otitis externa. The table below details some of the characteristic features of other causes:

Condition	Key features
Presbycusis	Presbycusis describes age-related sensorineural hearing loss. Patients may describe difficulty following conversations
Audiometry shows bilateral high-frequency hearing loss
Otosclerosis	Autosomal dominant, replacement of normal bone by vascular spongy bone. Onset is usually at 20-40 years - features include:
• conductive deafness
• tinnitus
• tympanic membrane - 10% of patients may have a 'flamingo tinge', caused by hyperaemia
• positive family history
Glue ear	Also known as otitis media with effusion
• peaks at 2 years of age
• hearing loss is usually the presenting feature (glue ear is the commonest cause of conductive hearing loss and elective surgery in childhood)
• secondary problems such as speech and language delay, behavioural or balance problems may also be seen
Meniere's disease	More common in middle-aged adults
• recurrent episodes of vertigo, tinnitus and hearing loss (sensorineural). Vertigo is usually the prominent symptom
• a sensation of aural fullness or pressure is now recognised as being common
• other features include nystagmus and a positive Romberg test
• episodes last minutes to hours
Drug ototoxicity	Examples include aminoglycosides (e.g. Gentamicin), furosemide, aspirin and a number of cytotoxic agents
Noise damage	Workers in heavy industry are particularly at risk
Hearing loss is bilateral and typically is worse at frequencies of 3000-6000 Hz
Acoustic neuroma (more correctly called vestibular schwannomas)	Features can be predicted by the affected cranial nerves
• cranial nerve VIII: hearing loss, vertigo, tinnitus
• cranial nerve V: absent corneal reflex
• cranial nerve VII: facial palsy

Bilateral acoustic neuromas are seen in neurofibromatosis type 2 |