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CHAP TER6 Theear
Congenital and genetic causes ofhearingloss
Congenital malformations of the inner ear cause hearing loss in some
adults. Genetic predisposition alone or combined with environmental
factors may also be responsible. More than 200 syndromes are known
to be associated with hear ingloss.
Causes ofhearing loss inadults
The main causes of deafness in the adult population are wax impaction
and ageing (presbycusis in the over60s).
bOtosclerosis
This is the formation of new bone occurring within the inner ear resulting
in immobility of the auditory ossicles and conductive deafness.
bDrug induced
Drugs that are renal toxic are commonly ototoxic, e.g. c ytotoxics, systemic aminoglycosides. Many other drugs are also ototoxic.
bPresbycusis
This is the gradual onset of (usually) bilateral sensorineural hearing loss
that occurs as with ageing. It is most pronounced at higher frequencies,
with diculty hearing in noisy environments. The aetiology is multifactorial. Risk factors include previous noise exposure, ototoxic medications,
and family history. In the UK, approximately 50% of those over 55year s
of age have some degree of hearing impairment. It is a diagnosis of exclusion. In mild cases, reassurance and advice (e.g. face- to- face communication can help). In more severe cases, hearing aids can be of benet.
bNoise - induced hearingloss
Noise- induced hearing loss results from recreational as well as occupational activities and often begins in adolescence. High- r isk activities
require that the user wears hearing protection.
Sudden onset ofsensorineural hearingloss
Sudden onset of unilateral hearing loss, with or without tinnitus, may
represent an inner ear viral infection or a vascular accident. Patients usually complain of reduced hearing, poor sound localization, and diculty
hearing clearly with backgroundnoise.
Gradual loss ofhearing
Gradual progression in a hearing decit is common with otosclerosis,
noise- induced hearing loss, acoustic neuroma s, and Ménière’s disease. In
addition to hearing loss, Ménière’s disease may be associated with episodic vertigo, tinnitus, and aural fullness. Hearing loss with otorrhoea is
most likely due to chronic otitis media or cholesteatoma.
Mixed hearingloss
Mixed hearing losses are due to pathology that can aect the middle
and inner ear simultaneously; causes include otosclerosis involving the
ossicles and the cochlea, transverse and longitudinal temporal bone fractures, head trauma, chronic otitis media, cholesteatoma, and middle ear
tumours.
DIZZINESS/‘VERTIGO’
Management ofhearingloss
• Hearing aids:these vary in size, site congur ation, and strength.
• Cochlear implants:cochlear implants conver t sound energy to
electrical signals and can be used to stimulate the auditor y division
of the eighth nerve directly. Amicrophone picks up acoustic
information that is sent to an external speech processor (located on
the body or at ear level). This processor converts the mechanical
acoustic wave into an electric signal that is tr ansmitted via the
surgically implanted electrode in the cochlea to the auditory nerve.
With the current generation of multichannel cochlear implants,
almost 75% of the patients with these implants are able to converse
on the telephone.
cDizziness/ ‘vertigo’
Vertigo is dened as the sensation of movement, even though the patient
is motionless. However, patients with an injury to the vestibular system
usually complain of ‘diz ziness’. Dysfunction of the peripher al or central
vestibular system causes asymmetry in signal input into the vestibular
centres, resulting in vertigo, nyst agmus, vomiting, and a sense of falling
toward the side of the injur y. Duration of symptoms and loss of hearing
are useful diagnostic clues (Table 6.2). Disorders of the middle and inner
ear can also cause these symptoms. They include:
• Impac tedwax
• Acute otitismedia
• Otitis media with eusion
• Chronic suppurative otitismedia
• Trauma (temporal bone fracture)
• Labyrinthitis and vestibular neuronitis
• Ménière’s disease (endolymphatic hydrops)
• Otosclerosis/ otoscleroticdrugs
• BPPV
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Table6.2 Dierential diagnosis ofve rtigo based onit s duration a nd
thepr esen ce ofhea ringloss
Time No associated hearing loss Hearing lo ss present
Seconds Benign positional paroxysmal
Minutes Vertebral basilar insuciency
Hours Vestibulopathy Ménière’s disease
Days Vestibular neuronitis Labyrinthitis
Weeks CNS disorders
vertigo
Migraines
Lyme disease
MS
Perilymphatic stula
Cholesteatoma
Acoustic neuroma
Autoimmune
Psychogenic
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CHAP TER6 Theear
• Iatrogenic (middle ear/ mastoid surgery)
• Cerebellopontine angle tumours
• Perilymphatic stulas
• Oto syphilis.
Remember non- auricular causes as well (cardiac, cer vical, neurological, etc .).
In elderly patients, vertigo is often multifac torial with many systemic diseases
aecting balance.
What toask forin thehistory forvertigo
• Duration
• Periodicity
• Circumstance of the vertigo
• Presence of other neurological signs or symptoms
• Hearingloss
• Otalgia.
What tolookfor
• Head and neck examination, including cranialner ves
• Spontaneous and gaze- evoked nystagmus
• Positional testing— Dix- Hallpiketest
• Cerebellar tests— r apid alternating movements (e.g. nger tonose)
• Posture — Romberg, tandem walking andgait
• Head thrust and headshake—check for nystagmus
• Dynamic visual activit y— look at Snellen char t with head shake
(worsening by >2 lines onchart)
• Ocular examination — range of eye movement, pupil size, and
symmetry
• Corneal reex, trigeminal anaesthesia.
Management ofpatients withdizziness
• Precautions:avoid heights, driving, and operating heavy machinery
when symptomatic.
• Acute vestibular suppressants:these are indicated for intolerable
symptoms but only in the short term. Prolonged use can delay
central compensatory mechanisms; common medications include
prochlorperazine, phenothiazine, meclizine, cinnarizine, diazepam,
and antiemetics.
• Vestibular rehabilitation:(exercise and physiotherapy) indicated for
chronic complaint s, involve positional tasks, head movements, and
oculomotor exercises to facilitate central compensation.
• Surgical treatment:may be indicated for specic diagnoses
(intratympanic gentamycin for Ménière’s disease).
cLabyrinthitis and vestibular neuritis
• Vestibular neuritis is inammation of the vestibularnerve.
• Labyrinthitis is inammation of the labyrinth in the inner ear, although
the vestibular nerve may also be involved.
The causes and symptoms of both these conditions are similar and it
is often impossible to tell which one is present. If there is hear ing loss,
labyr inthitis is more likely (because the cochlea may also be inamed).
Vestibular neuritis may be associated with nystagmus. Both conditions
DIZZINESS/‘VERTIGO’
result in unilateral vestibular dysfunction. This can result in loss of balance, vertigo, hearing loss, and tinnitus. The underlying cause is believed
to be a viral infection (as symptoms usually follow a URTI), but it can also
occur from bacterial infection, head injury, or from taking certain drugs.
Some cases of vestibular neuritis are thought to be caused by an infection of the vestibular ganglion by herpes simplex virus type 1.Infective
labyr inthitis can cause permanent hearingloss.
Signs and symptoms
One of the main symptoms is severe vertigo. Nausea, anxiety, and a general feeling of being unwell are also common. Examination will demonstrate nystagmus.
Management
Prochlorperazine or cinnarizine is commonly prescribed to help alleviate ver tigo and nausea. Some author ities suggest that viral labyrinthitis
should be treated early with steroids and antiviral medication. Vestibular
rehabilitation therapy may help reduce any residual dizziness from labyrinthitis. This works by challenging the vestibular system and stimulating
adaption.
cMénière’s disease (endolymphatic hydrops)
Ménière’s disease is an idiopathic inner ear disorder characterized
by attacks of vertigo, uctuating hearing loss, tinnitus, and aural fullness. Patients typically present in the fth decade of life. The cause of
Ménière’s disease is unknown. Anatomical, infectious, immunological,
and allergic factors have all been sug gested. The endolymphatic sac may
also be defective. This is impor tant in inner ear metabolism.
Presentation
Episodic attacks last for hours. The main symptoms and signs include
• Unilateral, uctuating sensorineural hearing loss (often low
frequency)
• Ver tigo that lasts minutes tohours
• Increasing tinnitus typically before or during the vertiginousattack
• Aural fullness.
The acute att ack is also associated with nausea and vomiting, and afterwards patients feel exhausted for a fewdays.
Investigations
Ménière’s disease is a clinical diagnosis. Electrophysiological studies and
imaging are obtained as needed but there is no diagnostic test specically
for Ménière’s disease. Audiology shows a low- frequency sensorineural
hearing loss. Electrocochleography and electronystagmography (ENG)
may be needed in atypical presentation or if ablative therapy is consid ered. ENG with caloric testing shows peripheral vestibular dysfunction.
Management
• Dietar y modications (sodium- restricted diet, dietar y restrictions
on caeine, nicotine, alcohol, and foods containing theophylline, e.g.
chocolate).
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CHAP TER6 Theear
• Acute attacks are managed with vestibular suppressants
(e.g. meclizine and dia zepam) and antiemetic medications
(e.g. prochlorperazine).
• Aminoglycoside therapy:medically refractory patients may benet
from intratympanic gentamicin therapy.
• Steroid therapy:acute exacerbation of Ménière’s disease may
respond to a short burst of oral steroids. Intratympanic steroids
have also been used to treat active disease and avoid the systemic
complications associated with oral steroids.
• Surgical measures:patients who have failed medical and gentamicin
treatment may require surgical intervention. Endolymphatic sac
surgery and vestibular nerve sections preserve hearing while
labyrinthectomy ablates hearing.
• ENT follow- up advised.
cBenign paroxysmal positional vertigo
BPPV is one of the most common t ypes of peripheral vertigo, arising as
a result of debris in the posterior semicircular canal. It can aect any age
but more commonly aects those over 50 years of age. Patients complain of vertigo lasting seconds, with no associated hearing loss and when
in cer tain positions. Nearly 20% of patients seen at ver tigo clinics have
BPPV; 20% have a preceding history of vestibular neuronitis; and another
20% have a history of head trauma.
BPPV occurs because a semicircular canal has debris either at tached
to the cupula or free oating in the endolymph. The semicircular canal
becomes stimulated by the movement of these particles in response to
gravity. Movement of the debris within the endolymph stimulates the
hairs lining the canal which in turn connect to the vestibular nerve. The
resultant conicting signals from the side aected in comparison to
the unaected side cause the ver tigo sensation.
Presentation
Patients usually complain of a sudden onset of vertigo that last s 10– 20
seconds with certain head positions (rolling over in bed, getting out of
bed, looking up, and bending over). This occurs as the calcium cr ystals
(otoliths) in the labyrinth move. Audiogram and tympanogram should be
normal. Asymmetric hearing loss calls into question the diagnosis of BPPV
and further evaluation is required.
Management
• Particle repositioning manoeuvres (such as Epley’s).
• Abone vibrator may also be placed on the mastoid bone during the
manoeuvres to loosen the debr is. 80% of patients are cured by a
single repositioning manoeuvre. If the symptoms persist or if patients
have recurrent symptoms, it may be repeated.
• Generally symptoms are resistant to medical management.
• Surgical treatment is rarely indicated but includes posterior
semicircular canal occlusion or singular neurectomy.
TINNITUS (RING ING/BUZZING IN THEEAR)
Epley’s manoeuvre (modicationsexist)
Only perform this if you have been shown how to do so and if there are
no contraindications.
• Sit the patient upright, with the legs fully extended and the head
rotated 45 degrees towards the aectedside.
• The patient is then quickly and passively forced down backwards into
a supine position with the head held approximately in a 30 degree
neck extension (Dix– Hallpike position). The aected ear faces the
ground.
• Observes the patient’s eyes for nystagmus for approximately
1– 2 minutes.
• The patient’s head is then turned 90 degrees to the opposite side so
that the aected ear faces up, while maintaining the 30 degree neck
extension. Remain in this position for approximately 1– 2 minutes.
• Keeping the head and neck xed relative to the body, the patient rolls
onto their shoulder, rotating the head with the body. The patient
should now be looking downwards at a 45- degreeangle.
• Observe the eyes for nystagmus for approximately 1– 2 minutes.
• Finally, the patient is slowly brought up to an upright sitting posture,
while maint aining the 45- degree rot ation of the head. The patient
holds this position for up to 30 seconds.
This may be repeated t wo more times. Post treatment the patient may
wear a sof t collar during the day to avoid any head positions that may
precipitate symptoms. They are advised to be careful bending, lying
backwards, moving the head up and down, or tilting it to eitherside.
Contraindications toEpley’s manoeuvre
• Severe carotid stenosis
• Unstable heart disease
• Severe neck disease
• Advanced rheumatoid arthritis.
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cTinnitus (ringing/ buzzing intheear)
Tinnitus can aect up to one in ve of the general population with a high
prevalence after noise exposure. Tinnitus can be classied as subjective and objective. Subjective tinnitus is the perception of sound in the
absence of any acoustic or external stimuli. Objective tinnitus is perception of sound caused by an internal body sound or vibration (bruit , hum,
palatal myoclonus). Subjective tinnitus is more common and is typically
associated with high- frequency hearing loss in old age. The pathophysiology of subjective tinnitus is largely unk nown although it may involve the
subcortical auditory pathways. If tinnitus is unilateral and accompanied by
unilateral sensory neural hearing loss, this may indicate acoustic neuroma.
Persistent pulsatile tinnitus may warrant imaging to rule out paragangliomas
or aberrant vascular anomalies in the middle earcleft.
204
CHAP TER6 Theear
Noise can also arise from many causes, including conditions of the
TMJ, Eustachian tube, and carotid artery. Causes include:
• Wax impaction
• Insects
• Otosclerosis
• Glueear
• Noise induced
• Presbycusis
• Ménière’s disease
• Trauma/ tympanic membrane perforation
• Ototoxicdrugs
• Labyrinthitis
• Acoustic neuroma
• AVM s
• TMJ disorders
• Glomus jugulare
• Carotid body tumours
• Patulous Eustachian tube and palatal myoclonus.
Management
• Hearing aids:for tinnitus associated with hearing loss. This reduces
tinnitus by amplifying ambient sound to maskit.
• Ma sker s:these utilize a band of white noise centred around the
tinnitus; indicated for intractable tinnitus.
• Tinnitus retraining therapy and tinnitus counselling by hearing
therapists/ relaxation techniques.
• Drug therapy:benzodiazepines, tricyclic antidepressants, and
carbamazepine; may result in some improvement.
• Refer to a tinnitus supportgroup.
• For further information, see http:// www.tinnitus.org.uk.
bWax impaction
This is a common cause of tinnitus and conductive hear ing loss. It is readily identied by auroscope examination where the t ympanic membrane
is often obscured. Can be compounded by repeated attempt s by the
patient to tr y to remove with cotton buds. Best removed by means of
aural micro - suction, which is often carried out in a nurse- led clinic and
facilitated by an ENT referral.
cForeign body/ insects
Often there is no clear history of inser tion and therefore it is impor tant
to remember that foreign bodies can present with ear ache or discharge.
If the foreign body has been present for a period of time visualization can
be obscured by wax build- up on auroscope examination. If the patient
is cooperative it may be possible to at tempt removal. If there are no
suitable instr uments, or the patient is uncooperative, this will need ENT
referral for examination and removal. Insects in the ear can be very
distressing and can present with signicant excoriation or swelling of
theEAM.
TINNITUS (RING ING/BUZZING IN THEEAR)
Removing a foreignbody
• Calm and reassure the person (usually a child).
• If the object is sticking out and easy to remove, do so with forceps.
• Objects within the canal can sometimes be retrieved with an aur al
hook. If the patient is cooperative and the object smooth, a small
drop of superglue on the tip of an applicator mayhelp.
• If you think the object is lodged deep within the ear, or you cannot
see it, do not reach inside the ear canal with tweezers. This may do
more harm than good. Turn the patient’s head to the aected side
and let gravity help. Shake the head gently.
• If the object doesn’t come out,refer.
Removing aninsect
• Do not let the patient put a nger in the ear. This may cause the
insect to bite orsting.
• Turn the patient’s head so that the aected ear is up. Wait and see if
the insect ies or cr awlsout.
• If this doesn’t work, slowly pour mineral oil, olive oil, or baby oil into
the ear, gently pulling the ear lobe backward and upward (adult), or
backward (child). Water will not work, as insects can trap air and
therefore do not drown. Oil should drown or dislodge most creepycrawlies which will then oatout.
• Discuss with ENT even if this is successful, as small insect remains can
irritate theEAM.
bOtosclerosis
This is caused by abnormal bone remodelling within the middle ear, primarily aecting the st apes bone. It usually begins in one ear but will eventually aect both with a variable cour se. Typically it leads to a conductive
hearing loss but if progressive, the cochlear ner ves can be aected.
This results in deafness which commonly present s below the age of
30. The EAM and tympanic membrane appear normal on examination.
Audiometr y is required to quantify the degree of hearingloss.
Causes
Most cases are genetic in nature and can be inherited. Cer tain drugs may
cause this as a side eect. Paget’s disease and measles have also been
associated.
Management
• Hearing aids are usually very eective in the early stages of the
disease
• Surgery. Stapedectomy (or stapedotomy) may be required for
denitive treatment.
cTympanic membrane perforations
Rarely patients present with tympanic membrane perforation as an emergency. Often these are of infectious or traumatic aetiology. Symptoms
include hearing loss and tinnitus. Pain may precede per foration if there
has been a middle ear infection. There may also be a discharge. Diagnosis
is conrmed by otoscopic examination and audiography.
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CHAP TER6 Theear
Causes ofear drum perforation
• Acute/ chronic suppurative otitis media (most commoncause)
• Persistent perforation after extrusion of a grommet
• Trauma (blow to the ear, barotrauma, diving, water skiing, explosion,
forceful irrigation)
• Iatrogenic
• Cholesteatoma (associated with marginal perforations).
Types ofperforation
• Central:perforation does not involve the annulus, typically infectious
• Marginal:involves the annulus. There is a higher association with
cholesteatomas
• Subtotal:large defect with an int act annulus.
Management
This involves keeping the ear dry and ear drops if infected. Send an ear
swab if there is per sistent discharge. Refer to ENT. Tympanoplasty may
be required for a persistent perforation.
bEustachian tube problems
bEustachian tube dysfunction
This is a condition in which the Eust achian tube fails to provide adequate
ventilation to the middle ear. The resultant decreased air pressure in the
middle ear places the tympanic membrane under tension. It then fails to
vibrate correctly in response to sound waves. This results in mued or
dull hearing. Temporary dysfunction is commonly experienced by many
people during take- o and landing when travelling by air. Symptoms can
last from a few hours to several weeks depending on the cause. Any
cause of tube blockage, tube inammation or failure of the tube to open
can cause Eustachian tube dysfunction. Common precipitants include
URTI, glue ear, allergies, or enlarged adenoids. More rarely, especially if
presenting in older patients, tumours in the nasopharyngeal region should
be excluded. Often symptoms are shor t- lived and no cause is identied. Nasal decongestants can help in cases where allergy is suspected.
Where symptoms persist, ENT opinion should be sought.
bPatulous Eustachiantube
This is a benign condition in which the Eustachian tube fails to close normally, remaining patent most of the time. It doesn’t typically lead to ear
problems or otitis media. However, patient s can repor t autophony (hearing one’s own voice and breathing) or mued sounds, due to variations in
pressure associated with respiration being tr ansmitted to the middle ear.
Patulous Eustachian tube can be associated with weight loss, mucosal scarring secondary to surgery, inammation, or radiation, and neuromuscular
disorders causing muscle atrophy such as MS or following a stroke. PET can
be misdiagnosed and treated as congestion, however decongestants and steroids spray are ineective. Diagnosis is based on clinical evaluation that can
be conrmed by nasendoscopy and audiology and tympanogram studies.
Mild cases may only require reassurance; potassium iodide treatment can
have a role in thickening secretions, in more moderate cases, with surgical
management reserved for failure of medical management.
MISCELLANEOUS CONDITIONS
Miscellaneous conditions
bChondrodermatitis nodularis helicis
These are painful, tender, erythematous paulonodules localized to the
pinna with occasional scale or cr ust. The superior par t of the helix is
most frequently aected but lesions have been reported all around the
pinna. Despite the lesion being only a few millimetres wide, it results in
exquisite tenderness. The condition most commonly aects men from
the age of 40 and above. Trauma, pressure (headphones, pillows), and
cold are thought to be pathogenic factor s. The patient is advised to avoid
pressure to the aected area. Treatments include intralesional steroids,
cryotherapy, or surgical removal of the inamed car tilage.
bArteriovenous malformation and venoushum
A form of pulsatile tinnitus dened as the perception of sound heard with
a regular rhythm corresponding to the heart beat. It typically is described
as a ‘whooshing’ noise, rather than a ‘ringing’ and can be positional with
the sound intensity inuenced by head movement. When examining it is
impor tant to auscultate for an audible bruit in the neck, as pulse synchronous tinnitus that can be heard on auscultation is referred to as objective pulsatile tinnitus and suggests a vascular aetiology. There are sever al
potential vascular causes such as AVM, usually involving branches of the
external carotid arter y. These patients should be referred.
bGlomus jugulare tumours
Glomus jugulare tumours, also known as jugulotympanic paragangliomas
are vascular, commonly benign paragangliomas. They can ar ise either
from the promontory of the middle ear or the adventitia of the jugular bulb. As these tumours grow, they can ll the middle ear, resulting
in pulsatile tinnitus with or without conductive hearing loss. As they
enlarge further they can also erode bone, especially inferiorly, placing
cranial nerves at risk. Tumours may also impinge on the ossicles and the
tympanic membrane, impairing the motilit y of either or both. Patients
can present with hearing loss or lower cranial ner ve defects. A bluish
pulsatile mass may be visible on auroscope examination. CT is usually
required with arteriography for large tumours. Traditionally treated by
surgical removal, there is an increasing role for the use of stereotactic
radiation therapy.
bPalatal myoclonus
A rare condition in which rapid spasm of either the levator or tensor
veli palatini muscles causes a sensation of ‘click ing’ or ‘popping’ in the
ears or tinnitus. It is most often secondar y to a br ainstem or cerebellar
lesion such as pontine infarct but can occur in the absence of any structural abnormality. When associated with eye movements, it is known as
oculopalatal myoclonus.
bGout
Gout tophi (uric acid deposits under the skin), can occur typically in the
pinna, in association with chronic tophaceous gout. On examination they
can have a white or yellowish appearance and are not usually tender or
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