HEARING LOSS Flashcards

(145 cards)

1
Q

Structure and function of external auditory meatus?

A

From outside of ear to TM. Contains ceruminous glands which secrete cerumen and small hairs
Guides sound waves to TM and traps FBs

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2
Q

Structure and function of tympanic membrane?

A

A thin connective tissue membrane covered by skin externally and a mucous membrane internally
This separates the external and middle ear
It vibrates when hit by sound waves which vibrates the ossicles

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3
Q

What are the 3 auditory ossicles?

A

Malleus (“hammer”)
Incus (“anvil”)
Stapes (“stirrup”)

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4
Q

What does the malleus connect?

A

Tympanic membrane and incus

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5
Q

What does the incus connect?

A

Malleus and stapes

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6
Q

What does the stapes connect?

A

The incus and oval window

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7
Q

What are the 2 skeletal muscles that attach to the auditory ossicles? What are their functions?

A

Stapedius and tensor tympani

Protect ears from prolonged, loud noises

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8
Q

What is the oval window?

A

A membrane-covered opening connecting the middle and inner ear
It transforms vibrations into fluid waves

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9
Q

What is the round window?

A

A membrane-covered opening that relieves pressure created by fluid waves

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10
Q

What is the pharyngotympanic tube?

A

This is the Eustachian tube
A canal linking the middle ear and nasopharynx
Swallowing/yawning opens the tube to equalise middle ear cavity and atmospheric air pressure

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11
Q

What is the bony labyrinth?

A

A system of channels that house the memabrnous labyrinth and is fluid-filled

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12
Q

Pathway of sound waves?

A

Sound waves travel through the external ear canal and vibrate the TM. This vibrates the ossicles which amplify the sound. The stales vibrates the oval window. Perilymph in scala vestibuli moves causing pressure waves which travel through the perilymph towards helicotrema, the cochlear duct and vibrates the basilar membrane
Hair cells bend by shearing force and cilia push against the tectorial membrane. When cilia bend in 1 direction there is an increase in potassium conduction which causes depolarisation. The opposite hyppens when cilia bend the other way. This generates an action potential within the cochlear nerve which sends signals to the brain = hearing

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13
Q

What is the cochlea?

A

A spiral bony chamber which coils around a central axis
This contains the organ of corti which is the site of auditory transduction
This has 2 receptors: inner and outer hair cells

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14
Q

What is the basilar membrane?

A

A membrane which is narrow and thick near the oval window/base and wide and thin near the cochlea
Function is for sound reception

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15
Q

What are the 3 chambers of the ear?

A

Scala vestibuli
Scala media
Scala tympani

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16
Q

What is the scala vestibuli?

A

The superior chamber filled with perilymph and conducts sound vibrations for hearing and proprioception
Connected to the middle ear through the oval window

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17
Q

What is the scala media?

A

The middle chamber of the ear
Filled with endoymph
Contains the cochlear duct

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18
Q

What is the scala tympani?

A

The inferior chambe filled with perilymph
Connected to the middle ear via the round window

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19
Q

Outline the tonotopic map?

A

This is the idea that sound frequencies displace the basilar membrane at different locations
At the base the fibres are short and stiff and 20,000Hz are needed to displace this. At the apex the fibres are long and floppy so only 20Hz is needed to displace this and therefore it responds best to low frequencies

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20
Q

What comprises the vestibular system?

A

3 semicircular canals
Otolith organs: utricle and saccule

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21
Q

Function of the semicircular ducts?

A

Rotational acceleration to maintain balance

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22
Q

Structure of the semicircular ducts?

A

3 canals at right angles to one another in each plane of space
Filled with endolymph
Has an ampulla which is a dilated portion at 1 end containing hair cells which protrude into a gelatinous substance

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23
Q

Outline how semicircular ducts work?

A

Head rotation means that endolymph deflects hair cells in certain directions within the semicircular canals. This changes from the baseline electrical firing rate which causes propagation down the vestibular nerve to the brain stem

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24
Q

What are the 2 otolith organs?

A

The utricle and saccule

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25
What is the function of the otolith organs?
The utricle and saccule
26
What do the otolith organs contain?
Hair cells with calcium carbonate crystals Maculae - the balance receptor q
27
How do the otolith organs function?
Moving your head in any direction = gravity deflects the calcium carbonate crystals attached to the hair cells. Stereoclia bend towards or away from kinocilium abd this causes depolarisation or hyperpolarisation respectively = excitation or inhibition respectively
28
Epidemiology of hearin gloss?
In the UK >11 million people are affected Prevalence increases with age 1/3rd of people over 65 have disabling hearing loss
29
Outline how the severity of hearing loss is scored?
The severity is based on the quietest sound that can be head measured in dB on pure tone audiometry: Mild: 25-39dB Moderate - 40-69 Severe: 70-94 Profound: >95
30
What is conductive hearing loss?
Abnormalities of the external or middle ear pathology which impair conduction of sound waves from the external ear through the ossicles in the middle ear to the cochlea in the inner ear
31
What is sensorineural hearing loss?
abnormalities in the cochlea, auditory nerve or other structures in the neural pathway leading from the inner ear to the auditory cortex
32
Causes of conductive hearing loss?
Impacted cerumen Foreign bodies Otitis externa and otitis media TM perforation Otosclerosis Cholesteatoma Middle ear effusion Neoplasm e.g. SCC of external ear Exostoses
33
What are Exostoses?
Hard bony growths in the ear canal that are associated with cold water swimming
34
What are causes of sensorineural hearing loss?
Presbycusis Noise exposure Sudden sensorineural hearing loss Ménière’s disease Exposure to ototoxic substances Labyrinthitis Vestibular schwannoma Neurological conditions e.g. stroke or MS Malignancy e.g. nasopharyngeal cancer or intracranial tumours Trauma to head or ear Systemic infections e.g. CMV, syphilis, meningitis, HIV, toxoplasmosis, Ramsay-hunt syndrome, Lyme disease Autoimmune conditions - RA, SLE, sarcoidosis, GPA Hereditary conditions - Alports syndrome
35
Whats the most common cause of sensorineural hearing loss?
Presbycusis
36
Aetiology of presbycusis?
Aetiology is multifactorial and includes degenerative changes associated with ageing, vascular changes, and genetic and environmental factors.
37
What is sudden sensorineural hearing loss?
Sudden onset (within 72 hours) hearing loss of 30dB hearing level or more which involves 3 consecutive frequencies and cannot b explained by external/middle ear conditions In 90% its considered idiopathic Hearing loss ranges from mild to profound and can be temporary or permanent
38
What are examples of ototoxic substances?
Drugs - aminoglycoside antibiotics, loop diuretics, NSAIDs, aspirin, anti-malarial, cytotoxic drugs Environmental - pesticides, cigarette smoke, heavy metals e.g. mercury and lead
39
What is a vestibular schwannoma?
A benign tumour which can cause hearing loss by compressing the cochlear nerve
40
What is Alports syndrome?
A genetic condition X-linked dominant pattern that causes a defect in the gene coding for type 4 collagen = abnormal GBM Seen in children. Associated with progressive renal impairment and bilateral sensorineural hearing loss
41
At what Hz does noise-induced hearing loss tend to occur?
Not before 4000Hz
42
What should you worry about with unilateral hearing loss?
Acoustic neuroma
43
What should you do when a pt presents with sudden sensorineural hearing loss?
Urgent referral to ENT for an MRI to exclude a vestibular schwannoma
44
How is sudden-onset sensorineural hearing loss usually managed by ENT?
High-dose oral corticosteroids
45
Questions to ask in the history for hearing loss?
Duration Onset? Laterality Progression Fluctuation Vertigo, tinnitus, otalgia, otorrhoea, sensation of fullness, neurological symptoms, URTI symptoms Recent head and neck trauma Recent air flight or diving experience Occupation exposure to noise Ototoxic meds FHx of hearing loss Social handicap - how has it affected communication, relationships, function, QOL, mood etc
46
How do you interpret webers test results?
Normal: sound is heard equally in both ears. Sensorineural hearing loss: sound is heard louder on the side of the intact ear. Conductive hearing loss: sound is heard louder on the side of the affected ear.
47
How do you interpret rinnes test results?
In healthy patients, air conduction should be better than bone conduction. Therefore, the pt should be able to hear the tuning fork held over the external auditory meatus for longer than the tuning fork held on the mastoid (air conduction >bone conduction). This may be the case in sensorineural hearing loss also. If there is conductive hearing loss then bone conduction may be better than air conduction. In this situation, the patient will be able to hear the tuning fork for longer when held on the mastoid than when held over the external auditory meatus However, a patient with significant sensorineural hearing loss may have a ‘false negative’ Rinne’s test, as they are unable to hear anything in the affected ear but bone vibrations may be transmitted to the unaffected ear.
48
Interpret these results: Positive Rinne’s (air conduction > bone conduction) Weber’s test is heard in the midline
Normal
49
Interpret these results: Positive Rinne’s (air conduction > bone conduction) Weber’s test is heard in the good ear
Sensorineural hearing loss
50
Interpret these results: Negative Rinne’s (bone conduction > air conduction) Weber’s test is heard in the bad ear
Conductive hearing loss
51
How does presbycusis present?
Slowly progressive bilateral high-frequency hearing loss from the age of 50 Pt may be unaware of their hearing loss Sometimes it can cause hyperacusis and tinnitus
52
Examination, otoscopy and tymapnometry findings in presbycusis?
All normal
53
Presentation of a FB causing hearing loss?
Most likely in children Hearing loss with discharge that may be foul-smelling or bloody if left long enough
54
What causes childhood deafness?
Most commonly caused by glue ear Syndromes e.g. Alports syndrome, CHARGE syndrome, Down’s syndrome Complications in pregnancy e.g. rubella, CMV, toxoplasmosis, herpes Ototoxic drugs Cleft palate or cleft lip can affect hearing Prematurity Infections in early childhood e.g. meningitis, measles, mumps Cholesteatoma Otosclerosis
55
Why is it important for childhood deafness be picked up asap?
To avoid deaf-mutism or delayed speech and social development
56
Symptoms of cerumen impaction?
Blocked feeling in ear Pain Conductive hearing loss (wax has to be against the TM and fully exclude the canal to affect hearing) Can cause vertigo and tinnitus Wax will be seen on otoscopy
57
Management of cerumen impaction?
3 drops of olive oil into the affected ear 3 times a day Other options include sodium bicarbonate drops, irrigation or referral to ENT outpatients for mechanical removal
58
Symptoms of otitis externa?
Ear pain and tenderness of the tragus or pinna Itch Ear discharge Less commonly causes hearing loss due to ear canal occlusion
59
What is swimmers ear?
Otitis externa
60
Otoscopy signs of otitis externa?
Red swollen and eczematous canal
61
Treatment of otitis externa?
Analgesia topical antibiotic or a combined topical antibiotic with a steroid if there is canal debris then consider removal if the canal is extensively swollen then an ear wick is sometimes inserted
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Causes of otitis externa?
infection: bacterial (Staphylococcus aureus, Pseudomonas aeruginosa) or fungal seborrhoeic dermatitis contact dermatitis (allergic and irritant) recent swimming is a common trigger of otitis externa
63
What is malignant/necrotising otitis externa?
A life-threatening complication of otitis externa where there is an invasive bacterial infection involving the external ear canal and skull base
64
How does necrotising otitis externa present?
Unremitting disproportionate ear pain headache purulent otorrhoea Vertigo. Profound conductive hearing loss. Systemically unwell, high fever. Granulation tissue seen on the floor of the ear canal and at the bone-cartilage junction; exposed bone in the ear canal. Ipsilateral facial nerve palsy.
65
What investigation shold you do if you suspect necrotising otitis externa?
CT head
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What most commonly causes necrotising otitis externa?
Pseudomonas aeruginosa
67
Who is necrotising otitis externa most common in?
Those with immunsisppression 90% of cases occur in pt with diabetes
68
What can necrotitis otitis externa progress to?
Temporal bone osteomyelitis
69
How common is otitis media?
50% of children have 3 or more episodes by the age of 3
70
What causes otitis media?
caused by bacteria or viruses and commonly these occur together; viral URTI precedes and disturbs the normal nasopharyngeal microbiome which allows bacteria to infect Most commonly strep pneumonia, H. Influenza, moraxella catarrhalis
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Symptoms of otitis media?
Otalgia Fever Hearing loss Ear discharge if TM perforates holding, tugging, or rubbing of the ear
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Otoscopy findings of otitis media?
A distinctly red, yellow, or cloudy tympanic membrane. Moderate to severe bulging of the tympanic membrane, with loss of normal landmarks and an air-fluid level behind the tympanic membrane (indicates a middle ear effusion). Perforation of the tympanic membrane and/or discharge in the external auditory canal.
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Treatment of otitis media?
Advise that the usual course of acute otitis media is about 3 days, but can be up to 1 week Analgesia Ask parents to seek help if symptoms dont improve after 3 days Antibiotics can be given in certain situations - 5-7 days of amoxicillin
74
In which situations with otitis media would you give antibiotics?
• Symptoms lasting more than 4 days or not improving • Systemically unwell but not requiring admission • Immunocompromise or high risk of complications secondary to significant heart, lung, kidney, liver, or neuromuscular disease • Younger than 2 years with bilateral otitis media • Otitis media with perforation and/or discharge in the canal
75
Common complication of otitis media?
Mastoiditis Brain abscess Meningitis Facial nerve paralysis
76
What is “glue ear”?
Otitis media with effusion
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Does acute otitis media or otitis media with effusion more characteristically cause hearing loss?
OME
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How common is otitis media with effusion?
Very common Majority of children will have at least 1 episode during childhood Peaks at 2 years
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Risk factors for glue ear?
Males Siblings with it Winter/spring time Bottle feeding Day care attendance Parental smoking
80
Presentation of OME?
Hearing loss Mild intermittent ear pain with fullness or 'popping' may occur. Tinnitus. Aural discharge — persistent foul-smelling discharge requires urgent referral. Recurrent acute otitis media infections, upper respiratory tract infections, or frequent nasal obstruction or rhinorrhoea.
81
Otoscopy findings in OME?
TM appears dull and there may be a fluid level visible or air bubbles
82
How do we diagnose OME?
Pneumatic otoscopy can be used Tympanometry may be used to improve the accuracy of a diagnosis Audiometry should be carried out by trained staff, using tests suitable for the developmental stage of the child to determine the level of hearing loss.
83
Management of OME?
Active observation for 3 months Surgical options: Myringotomy and insertion of grommets Hearing aids may be offered to children with persistent bilateral OME and hearing loss
84
What are grommets?
Tubes that allow air to pass through into the middle ear and hence do the job that is normally done by the Eustachian tube A small incision is made in the eardrum and the fluid behind the eardrum can be drained. A very small hollow tube is placed across the eardrum to allow air to pass through into the middle ear and equalise the air pressure. As the child grows these will fall out and the TM will heal itself. They provide an immediate restoration of hearing
85
How common is tinnitus?
At least 30% of UK population experience at some point in their life
86
Causes of tinnitus?
Idiopathic Pesbycusis Ménière’s disease Noise induced hearing loss Ototoxicity Otosclerosis SSNHL Impacted ear wax Rarely: acoustic neuroma
87
How do we investigate tinnitus?
Otoscopy Pure tone audiogram Pt completes tinnitus handicap inventory questionnaire MRI of internal auditory meatus only needed if unilateral (sign of acoustic neuroma) or neurological signs or pulsatile tinnitus
88
What is pulsatile tinnitus?
When the sound of tinnitus heard is synchronous with the heartbeat
89
What causes pulsatile tinnitus?
Turbulent blood flow reaching the cochlear: - atherosclerosis of ICA - vascular malformations - GLOMUS tumours - Paget’s disease - otosclerosis - myoclonus of middle ear or palatal muscles
90
Treatment of tinnitus?
investigate and treat any underlying cause amplification devices - more beneficial if associated hearing loss White noise generators psychological therapy may help a limited group of patients e.g. cognitive behavioural therapy tinnitus support groups
91
What is habituation in regards to tinnitus?
you become accustomed to a tinnitus experience. This means that you might still have tinnitus but you are no longer aware of
92
What is Ménière’s disease?
A long term inner ear disorder caused by an excessive buildup of endolymph in the labyrinth of the inner ear, causing a higher pressure than normal and disrupting sensory signals (endolymphatic hydrops)
93
What age does Ménière’s disease typically affect?
Middle aged 40-50
94
Presentation of Ménière’s disease?
recurrent episodes of vertigo (this is the most prominent Sx), tinnitus and sensorineural hearing loss that last mins-hours. The episodes can come in clusters over several weeks! a sensation of aural fullness or pressure is now recognised as being common other features include nystagmus and a positive Romberg test typically symptoms are unilateral but bilateral symptoms may develop after a number of years
95
Prognosis of Ménière’s disease?
Symptoms resolve in the majority of pt after 5-10 years Majority of pt will be left with a degree of hearing loss Psychological distress is common!
96
How to make a diagnosis of Ménière’s disease?
It’s clinical but made by an ENT specialist Pts usually need an audiology assessment to evaluate hearing loss Pts need to inform DVLA
97
Management of acute attacks of Ménière’s disease?
Buccal or IM prochlorperazine Sometimes admission is required
98
How can you prevent episodes of Ménière’s disease?
Betahistine Vestibular rehabilitation exercises
99
What are acoustic neuromas?
BENIGN tumours of the Schwann cells surrounding the vestibulocochlear nerve that innervates the ear These occur at the cerebellopontine angle (account for 90% of cerebellopontine angle tumours!)
100
What is usually associated with bilateral acoustic neuromas?
Neurofibromatosis type 2
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What age do acoustic neuromas usually present?
40-60
102
How do acoustic neuromas usually present?
Gradual onset… Unilateral sensorineural hearing loss Unilateral tinnitus Dizziness Sensation of fullness in the ear Can be associated with a facial nerve palsy if the tumour grows large enough (full face no forehead sparing!)
103
Investigations for suspected acoustic neuroma?
Refer urgently to ENT Otoscopy - normal Audiometry - sensorineural hearing loss MRI of cerebellopontine angle
104
Management of acoustic neuroma?
Conservative management with monitoring may be used if there are no symptoms or treatment is inappropriate Surgery to remove the tumour (partial or total removal) Radiotherapy to reduce the growth
105
What is the most common cause of a perforated tympanic membrane?
Infection Others: barotrauma, direct trauma e.g. cotton buds
106
Presentation of tympanic membrane perforation?
May be hearing loss dependant on the size May be blood in the ear canal May have tinnitus, ear pain, itch in ear, dizziness etc May have symptoms of otitis media as puts at risk for this
107
How do we investigate a tympanic membrane perforation?
Otoscopy - may be a visible defect
108
Management of tympanic membrane perforation?
no treatment is needed in the majority of cases as the tympanic membrane will usually heal after 6-8 weeks. Keep ear dry NICE suggest prescribing antibiotics to perforations which occur following an episode of acute otitis media. myringoplasty may be performed if the tympanic membrane does not heal by itself
109
What is otosclerosis?
A condition where there is remodeling of theossicles in the middle ear and this mainly leads to the base of the stapes attaching to the oval window and causing stiffening and preventing transmission of sound effectively = conductive hearing loss
110
What causes otosclerosis?
Thought to be a combination of environmental and genetic factors Inherited in AD pattern
111
How does otosclerosis present?
Pt under 40 with gradual onset uni/bilateral conductive hearing loss and tinnitus It tends to affect the hearing of lower-pitched sounds so female speech may be easier to hear!
112
Examination findings for otosclerosis?
Otoscopy - normal. In 10% may have ‘flamingo tinge’ caused by hyperaemia Webers - normal if bilateral. Louder in affected ear if U/L Rinnes - shows conductive hearing loss
113
Investigations for otosclerosis?
First line - Audiometry will show conductive hearing loss Tympanometry will show reduced admittance as TM is stiff and non-compliant High resolution CT can detect boney changes associated with otoscleoris but are not always required
114
Management of otosclerosis?
Conservative with hearing aids Surgical - stapedectomy or stapedotomy (this leaves the base of the stapes attached and uses a prosthesis to transmit sound from the incus to the cochlea)
115
What is Cholesteatoma?
An abnormal collection of squamous epithelial cells in the middle of the ear This is non-cancerous but can invade local tissues and nerves and erode bones of middle ear
116
Pathophysiology of Cholesteatoma?
Not fully understood… Main theory is that negative pressure in the middle ear due to Eustachian tube dysfunction causes a pocket of the TM to retract into the model ear. The squamous epithelial cells of this pocket continue to proliferate and grow into the local area. This can damage the ossicles and cause hearing loss
117
Who does Cholesteatoma typically affect?
Patients 10-20 Being born with a cleft palate increases the risk 100 fold
118
Presentation of Cholesteatoma?
Foul-smelling non-resolving discharge Unilateral conductive hearing loss Vertigo, facial nerve palsy, cerebellopontine angle syndrome depending on local invasion
119
Otoscopy findings in Cholesteatoma?
Attic crust - seen in uppermost part of ear drum
120
Investigation to diagnose Cholesteatoma?
CT head Refer to ENT
121
Management of Cholesteatoma?
Surgical removal by ENT
122
What is a glomus tympanicum tumour?
These are the most common vascular tumours of the middle ear
123
How do glomus tympanicum tumours present?
Pulsatile tinnitus Feeling of fullness on ear Hearing loss
124
Otoscopy findings of glomus tympanicum tumours?
Red/blue mass visible behind the normal TM
125
What is labyrinthitis?
Inflammation of the bony labyrinth of the inner ear (vestibular and cochlear end organs) usually from a viral URTI but can be bacterial
126
How is labyrinthitis different from vestibular neuritis?
vestibular neuritis is used to define cases in which only the vestibular nerve is involved, hence there is no hearing impairment; Labyrinthitis is used when both the vestibular nerve and the labyrinth are involved, usually resulting in both vertigo and hearing impairment.
127
Average age of onset of labyrinthitis?
40-70
128
Presentation of labyrinthitis?
Acute onset…. Vertigo Others: N&V Sensorineural hearing loss Tinnitus Preceding or concurrent viral URTI symptoms Spontaneous unilateral horizontal nystagmus to unaffected side Abnormal head impulse test Gait disturbance - pt may fall towards afefcted side
129
How is labyrinthitis diagnosed?
Clinical diagnose The head impulse test is useful for diagnosis of this and vestibular neuritis
130
Management of labyrinthitis?
episodes are usually self-limiting prochlorperazine or antihistamines may help reduce the sensation of dizziness
131
Types of audiometric assessments?
Pure tone audiometry Tympanometry Evoked response audiometry or auditory brainstem response
132
What is pure tone audiometry?
This is the gold standard assessment This test helps find the quietest sound you can hear at different pitches, or frequencies.
133
What are audiograms?
Charts that document the volume at which pt can hear different tones X-axis - frequency Hz Y-axis - volume dB - loud at bottom quiet at top The louder the sound required for the patient to hear, the worse their hearing is and the lower on the chart they will plot.
134
Describe the symbols used in audiometry?
X – Left-sided air conduction ] – Left-sided bone conduction O – Right-sided air conduction [ – Right-sided bone conduction
135
When a pt has normal hearing what will an audiogram show?
All readings will be between 0-20dB
136
When a pt has sensorineural hearing loss, what will an audiogram show?
both air and bone conduction readings will be more than 20 dB, plotted below the 20 dB line on the chart. This may affect only one side, one side more than the other or both sides equally.
137
When a pt has conductive hearing loss, what will an audiogram show?
Bone conduction readings will be normal (0-20 dB). However, air conduction readings >20 dB
138
When a pt has conductive hearing loss, what will an audiogram show?
Both air and bone conduction readings will be more than 20 dB However, there will be a difference of more than 15 dB between the two (bone conduction > air conduction).
139
What is normal pure tone average (dB)?
0-24dB
140
Outline the pure tone averages (dB) for the severties of hearing loss?
Mild 25-50 Moderate 51-70 Severe 71-90 Profound 91-110 Total dead ear 110+
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When should you refer to ENT immediately within 24 hours?
• sudden onset (<3 days) unilateral or bilateral hearing loss which has occurred within the past 30 days and cannot be explained by external or middle ear causes • Unilateral hearing loss with focal neurology -> ?stroke • Hearing loss associated with head or neck injury • Hearing loss associated with a severe infection e.g. Ramsay hunt syndrome or necrotising otitis externa - otalgia and otorrhoea not responding to Tx within 72 hours in a person who is immunocompromised is suggestive of necrotising otitis externa
142
When should you refer to ENT to be seen within 2 weeks?
• sudden onset (<3 days) unilateral or bilateral hearing loss which has occurred more than 30 days ago and cannot be explained by external or middle ear causes • Rapidly progressive hearing loss (4-90 days) which cannot be explained by external or middle ear causes • Suspected head and neck malignancy e.g. unilateral hearing loss and middle ear effusion not associated with URTI or bloody discharge
143
When are implantable devices indicated for hearing?
patients with severe-to-profound hearing loss. In children, audiological assessment and/or difficulty developing basic auditory skills. In adults, patients should have completed a trial of appropriate hearing aids for at least 3 months which they have been objectively demonstrated to receive limited or no benefit from.
144
Prevention of deafness
• immunisation • Good maternal and childcare practices ◦ NHS newborn hearing screening programme ‣ Automated otoacoustic emissions ‣ Automated auditory brainstem responses are used to clarify findings if no clear response from AOAE during screening. Also used for babies who have spent >48 hours in NICU or SCBU • Genetic counselling • Identification and optimal management of a common ear condition • Occupational hearing conservation programmes for noise and chemicals exposure • Safe listening strategies for the reduction of loud noise exposure • Rational use of medicines to prevent ototoxic hearing loss • Not putting foreign bodies into the ears
145
complications of hearing loss?
• impacts relationships with family and friends due to communication diffiuclties • Affects social engagement and participation in leisure activities -> social withdrawal, isolation and loneliness • Affects employment and educational opportunities • Affects QOL and ability to function independantly • Increased risk of depression and anxiety • Increased risk of dementia - if severe 5 x more likely • Increased risk of difficulties in walking, postural control and falls