ENT: Ear Problems 1 Flashcards
(72 cards)
1
Q
Remind yourself of where the following are on the pinna of the ear:
- Helix
- Antihelix
- Tragus
- Antitragus
- Lobule
- External auditory meatus
- Concha
A
2
Q
Label the following diagram of ear, include:
- Ear canal
- Tympanic membrane
- Each of the ossicles
- Auditory (Eustachain) tube
- Round window
- Oval window
- Cochlea
- Semi-circular canals
- Vestibulocochlear nerve
A
3
Q
Label the following diagram of the tympanic membrane, include:
- Cone of light
- Handle of malleus
- Umbo (tip of malleus)
- Pars tensa
- Pars flaccida
- Incus
- Annulus
- Short process of malleus
- Anterior fold
- Posterior fold
A
4
Q
State some of the common hearing tests for adults and briefly describe what is involved in each
A
Pure tone audiometry= most common
5
Q
What does pure tone audiometry involve?
A
Test hearing by playing variety of tones at different volumes. Aim is to establish the quietest volume at which the patient can hear each frequency (tone). E.g. 1000Hz will be played at various volumes until pt can just about hear the sound then mark on the graph
6
Q
Briefly describe how pure tone audiometry is done
A
- Sound proof room
- Before test, examine ears for infection, foreign body or occluding wax
- Patient wears headphones to test air conduction, followed by a bone vibrator places on mastoid process to test bone conduction.
- Audiometer machine makes pure tone sounds at varying frequencies
7
Q
How is air conduction measured in audiometry?
A
Wear headphones and audiometer produces sounds of varying frequnecies at different decibels
8
Q
How is bone conduction measured in audiometry?
A
Vibrator placed on mastoid process
9
Q
For an audiogram, discuss what:
- Is on the Y axis
- Is on the X axis
- What an X means
- What an O means
- What a ] means
- What a [ means
A
- Y axis is volume (decibels/dB)
- X axis is frequency (Hz)
- X= left sided air conduction
- O= right sided air conduction (HINT: think Oh right)
- ]= left sided bone conduction
- [= right sided bone conduction (HINT: think looks like the pt’s right ear, vice versa for left)
10
Q
What decibel range is normal hearing?
A
All readings between 0-20dB
11
Q
What is the pure tone threshold?
A
Lowest decibel hearing level (i.e. quietest sound) at which the patient detects the pure tone at least 50% of the time
12
Q
Discuss how an audiogram will vary for sensorineural and conductive hearing loss
A
- Sensorineural: both air and bone conduction will be more than 20dB
- Conductive: bone conduction will be normal (0-20dB) and air conduction will be more than 20dB
13
Q
Discuss what an audiogram would show in a patient with mixed hearing loss
A
Both air and bone conduction will be more than 20dB however there will be a difference of more than 15dB between the two (in which bone conduction > air conduction)
14
Q
What is masking?
A
Masking is when you present a sound to the non-test ear (masking noise) to prevent it from detecting the sound being presented to the test ear.
15
Q
What would you see on the audiogram of someone with noise-induced hearing loss?
A
Boiler’s notch
16
Q
What type of hearing loss does this audiogram suggest?
A
Presbyacusis (showing bilateral high frequency hearing loss)
17
Q
What type of hearing loss is represented by each of the lines on the audiogram?
A
18
Q
What is the difference between conductive and sensorineural hearing loss?
A
- Conductive: problem with sound travelling from external environment to inner ear; problem with external or middle ear
- Sensorineural: problem with sensory system or vestibulocochlear nerve in inner ear
19
Q
Hearing loss may be associated with other symptoms; state some examples
A
- Tinnitus
- Vertigo
- Pain (indicate infection)
- Discharge (indicate middle or outer ear)
- Neurological symptoms
20
Q
State some causes of sensorineural hearing loss in adults
A
- Sudden onset sensorineural hearing loss (<72hrs)
- Presbyacusis
- Noise exposure
- Ménière’s disease
- Labyrinthitis
- Acoustic neuroma
- Neurological conditions (e.g., stroke, multiple sclerosis or brain tumours)
- Infections (e.g., meningitis)
- Medications
- Loop diuretics (e.g. furosemide)
- Aminoglycosides (e.g. gentamicin)
- Chemotherapy drugs (e.g. cisplatin)
21
Q
State some causes of conductive hearing loss in adults
A
- Blockage in ear canal (e.g. wax)
- Infection (e.g. otitis media or otitis externa)
- Effusion in middle ear
- Eustachian tube dysfunction
- Perforated tympanic membrane
- Otosclerosis
- Cholesteatoma
- Exostoses
- Tumour
22
Q
For Weber’s remind yourself:
- What tuning fork is used
- How to perform
- Normal result
- Result in sensorineural hearing loss
- Result in conductive hearing loss
A
- 512Hz
- Strike tuning fork to make it vibrate, place in centre of pt’s forehead, ask pt if they can hear sound and which ear is loudest in or if the same
- Normal= hears sound equally in both ears
- Sensorineural= sound louder in normal ear
- Conductive= sound louder in affected ear
23
Q
For Rinne’s, remind yourself:
- What tuning fork is used
- How to perform
- Normal result/Rinne’s positive
- Abnormal result/Rinne’s negative
A
- 512Hz
- Strike turning fork to make it vibrate, place flat end on mastoid process, tell pt to tell you when they can no longer hear the humming noise, when they can no longer hear it remove the tuning fork that is still vibrating and hover it 1cm from the same ear, ask if they can still hear the humming noise
- Normal/Rinne’s positive= pt can hear sound again when move tuning fork next to the ear (air>bone)
- Abnormal/Rinne’s negative= sound not heard after moving tuning fork next to hear (bone>air)
24
Q
What is sudden sensorineural hearing loss? **HINT: rule of 3
Is it permanent?
A
- Hearing loss of 30dB or greater over at least three contiguous audiometric frequencies occurring within <72hrs for which no conductive cause can be found; usually unilateral
- Hearing loss may resolve over days to weeks or may be permanent
**NOTE: causes of rapid onset hearing loss that are due to conductive problems (and hence not SSHL) include ear wax (or other blockage), infection, middle ear effusion, eustachian tube dysfunction, perforated tympanic membrane
25
A cause is identified for most cases of sudden sensorineural hearing loss; true or false?
FALSE; **90% cases are idiopathic**. Other possible causes include:
* Infection (e.g., meningitis, HIV and mumps)
* Ménière’s disease
* Ototoxic medications
* Multiple sclerosis
* Migraine
* Stroke
* Acoustic neuroma
* Cogan’s syndrome (a rare autoimmune condition causing inflammation of the eyes and inner ear)
26
If someone presents with _sudden sensorineural hearing loss within 30 days of onset_ what should you do?
Immediate (within 24hrs) referral to ENT for assessment
27
What investigations will be done in secondary care for sudden onset sensorineural hearing loss?
* **Audiometry:** required for diagnosis- GOLD STANDARD *(need a l_oss of at least 30 decibels in three consecutive frequencies_)*
* **MRI or CT head:** if considering acoustic neuroma or stroke
28
Discuss the management of sudden onset sensorineural hearing loss
Immediate (within 24hrs) referral to ENT if presented within 30 days of onset. ENT can then organise investigations and oversee treatment and follow patient up.
* **Idiopathic: steroids** (either PO or intra-tympanic)
* Most cases are started on PO high dose steroids in primary care whilst ENT organise urgent pure tone audiometry
* Other cause identified: treat the cause
*\*\*\*NOTE: intra-tympanic injections are injections through tympanic membrane*
29
What is presbycusis?
“**Age-related hearing loss**”. Type of **sensorineural hearing loss** that affects **high-pitched sounds first** due to atrophy of sensory hair cells and neurones in cochlea over time. It affects older patients and usually occurs **gradually and symmetrically.**
30
There are numerous different mechanisms proposed for presbycusis; state some of these
* Loss of hair cells in cochlea
* Loss of neurones in cochlea
* Atrophy of the stria vascularis *(produces endolymph)*
* Reduced endolymphatic potential *(electrochemical gradient required for hair cell mechanotransduction)*
31
State some risk factors for presbycusis- highlighting two key ones to remember
* **Age**
* **Loud noise exposure**
* Male gender
* Family history
* Diabetes
* Hypertension
* Ototoxic medications
* Smoking
32
Describe typical presentation of presbycusis
_Features:_
* Gradual hearing loss
* Affects high pitched sounds first *(pt may say finds male voices easier to hear)*
* Associated tinnitus
_Pt's may present because:_
* Others think they are not paying attention
* Concerns about dementia (when issue is hearing loss)
33
How is presbycusis diagnosed?
**_Audiometry_**
* Sensorineural
* Normal/near-normal hearing at low frequencies
* Poor hearing at high frequencies
34
Discuss the management of presbycusis?
Can't be reversed hence management focused on supporting individual to maintain normal functioning by e.g.:
* Hearing aids
* Assistive listening devices (e.g. for telephone, louder doorbells etc)
* Learning to lip read
* Optimising environments (e.g. reducing background noise during converations)
* Cochlear implants
35
Patients with presbycusis are more likely to develop \_\_\_\_\_?
**Dementia** (but treating hearing loss may reduce risk)
36
What is otosclerosis (include pathophysiology)
**Abnormal bone remodelling of ossicles** in middle ear, which results in **fixation of the stapes at the oval window**, leading to **conductive hearing loss** *(oto- ears, sclerosis- hardening)* as stapes can no longer transmit sound effectively.
37
What is the cause of otosclerosis?
Who does it affect more, men or women?
What age does it usually present by?
* Thought to be due to combination of environmental and genetic factors; can be inherited in autosomal dominant pattern
* More common in women
* Before 40yrs
38
Describe typical presentation of otosclerosis
Patient **\<40yrs with unilateral or bilateral**:
* **Hearing loss** *(affects lower pitched sounds first)*
* **Tinnitus**
* Talking quietly because to them their voice seems loud due to conductive hearing loss
39
What might you see on otoscopy of pts with otosclerosis?
Schwartz sign/flamingo tinge (red tinge to tympanic membrane on otoscopy)
40
What investigations would you do for someone with suspected otosclerosis?
* **Audiometry (initial investigation of choice):** *conductive hearing loss, worse at lower frequencies*
* **Tympanometry:** *reduced admittance (absorption) of sound*
* **CT scan of the ear** *(not always required)*
41
Discuss the management of otosclerosis
Options include:
* Conservatively with **hearing aids**
* Surgically with:
* **Stapedectomy** *(removing entire stapes bone and replacing with prosthesis)*
* **Stapedotomy** *(remove part of stapes bone but leave base of stapes/footplate attached to oval window then make hole in stapes for prosthesis to enter and other end hooks around incus)*
42
Why is it a problem if the Eustachian tube is not functioning properly?
* Cannot equalise air pressure
* Cannot drain fluid freely from middle ear
… both can result in middle ear filing with fluid
43
Describe typical presentation of Eustachian tube dysfunction
* Reduced or altered hearing
* Popping noises or sensations inear
* Fullness sensation in ear
* Pain or discomfort
* Tinnitus
*\*NOTE: symptoms get worse when external pressure changes and middle ear cannot equalise e.g. flying, climbing a mountain, scuba diving*
44
What investigations would you do if you suspect Eustachian tube dysfunction?
Investigations not usually required as it Eustachian tube dysfunction is associated with a clear cause. However, if persistent, severe or problematic then may do investigations:
* Tympanometry *(will show peak admittance with negative ear canal pressures)*
* Audiometry
* Nasopharyngoscopy
* CT scan ear
45
Explain what tympanometry involves
***Tympanometry*** involves:
* Inserting a device into the ***external auditory canal*** (ear canal)
* Creating different ***air pressures*** in the canal
* Sending a sound in the direction of the tympanic membrane
* Measuring the amount of sound reflected back off the ***tympanic membrane***
* Plotting a ***tympanogram*** (graph) of the sound absorbed (admittance) at different air pressures
The amount of sound absorbed by the tympanic membrane and middle ear (not reflected back to the device) is known as the ***admittance***.
Normally, sound is absorbed best when the air pressure in the ***ear canal*** matches the ***ambient air pressure***. The ambient air pressure is equal to the middle ear pressure in healthy ears.
When there is ***Eustachian tube dysfunction***, the air pressure in the ***middle ear*** may be **lower** than the ***ambient air pressure*** because new air cannot get in through the tympanic membrane to equalise the pressures. As a result, the ***tympanogram*** will show a peak ***admittance*** (most sound absorbed) with ***negative ear canal pressures***.
46
Discuss the management of Eustachian tube dysfunction
Various options for management:
* **No treatment** (wait for it to resolve spontaneously)
* Manoeuvres to inflate E.T
* **Valsalva** (hold nose & blow into it)
* Otovent (OTC device in which pt blows into balloon using single nostril)
* Pharmacological
* **Decongestant nasal sprays** (short term)
* **Antihistamines**
* Surgery
* To **treat pathology causing dysfunction** e.g. adenoids
* **Grommets** (to help equilibrize pressure)
* **Balloon dilation Eustachian tuboplasty**
*\*\*\*\*Balloon dilatation Eustachian tuboplasty:* *inserting a deflated balloon into the Eustachian tube, inflating the balloon for a short period (i.e., 2 minutes) to stretch the Eustachian tube, then deflating and removing it. This is usually done under general anaesthetic.*
47
What is an acoustic neuroma?
State 2 other names for an acoustic neuroma
* Benign tumours of Schwann cells surrounding the vestibular component (or of all parts???? ASK) of the vestibulocochlear nerve
* Alternative names:
* Vestibular schwannoma
* Cerebellopontine angle tumours (due to location)
48
Acoustic neuromas are usually unilateral; bilateral acoustic neuromas are associated with what?
Neurofibromatosis type II
49
Describe typical presentation of acoustic neuromas
Typically aged 40-60yrs presenting with **gradual onset of:**
* Unilateral **sensorineural hearing loss** (unless bilateral acoustic neuroma in which case bilateral)
* Unilateral **tinnitus**
* **Dizziness or imbalance**
* Sensation of **fullness** in ear
* **Absence of corneal reflex**
* May be associated with **facial nerve palsy** *(if large enough to compress facial nerve)*
50
For each of the symptoms of acoustic neuroma explain, in terms of structures affected, why pts get each of these symptoms
* CNVIII: sensorineural hearing loss, tinnitus, vertigo
* CNV: absent corneal reflex *(remember trigeminal nerve responsible for facial sensation)*
* CNVII: facial palsy
51
What investigations are required if you suspect an acoustic neuroma?
* **Audiometry**: *establish hearing loss*
* **CT or MRI brain/cerebellopontine angle**
52
Discuss the management of acoustic neuromas
Refer to ENT for management:
* **Monitor/observation** (often the case initially as they are slow growing & benign)
* **Surgery** to remove tumour
* **Radiotherapy**
53
State 2 potential risks associated with surgery for acoustic neuromas
* CNVIII nerve injury which may lead to permanent hearing loss or dizziness
* Facial nerve injury leading to facial weakness
54
What is a cholesteatoma?
**Abnormal, destructive collection/growth of keratinising squamous epithelial cells within the middle ear or mastoid air cells**; it can **invade local structures** (tissue, nerves, bones) and also predispose to infections.
*NICE definition: "A cholesteatoma is an abnormal sac of keratinizing squamous epithelium and accumulation of keratin within the middle ear or mastoid air cell spaces which can become infected and also erode neighbouring structures."*
55
Describe pathophysiology of cholesteatomas
Not fully understood but think that **Eustachian tube dysfunction** causes **negative pressure** in middle ear which causes part of tympanic membrane (usually pars flaccida) to **retract into middle ear**. Squamous epithelial cells, that originate from outer surface tympanic membrane, **continue to grow and proliferate into surrounding space and structures causing destruction** (can damage tissue, nerves and bones)
56
What is typical age of presentation for cholesteotomas?
Are there any risk factors?
* **10-20yrs**
* Being born with clef palate increases risk
57
Describe typical presentation of cholesteatomas
_Main features:_
* **Foul discharge**
* **Unilateral conductive hearing loss**
_Other features due to local invasion:_
* Vertigo
* Facial nerve palsy (e.g. facial weakness)
* Trigeminal nerve palsy (e.g. reduced facial sensation)
58
What might you see on otoscopy in pt with cholesteatoma?
* Presence of a **deep retraction pocket**, with or without granulation tissue and skin debris.
* **Crust or keratin in the upper part** of the tympanic membrane.
* The tympanic membrane may be **perforated**
59
What does a congenital cholesteatoma look like on otoscopy?
**White mass behind an intact tympanic membrane**, in a person with no prior history of ear discharge, tympanic membrane perforation, or surgical procedures on the ear.
60
What investigations are done if you suspect a cholesteatoma?
* **CT head to confirm diagnosis**
* May do MRI head if want to see soft tissues in more detail
61
Discuss the management of cholesteatomas?
Referral to ENT for surgical removal of cholesteatoma
62
When do pts with suspected cholesteatoma require emergency admission?
* Emergency admission should be arranged for people with a suspected cholesteatoma associated with a serious complication, including:
* A **facial nerve palsy**
* **Vertigo.**
* **Other neurological symptoms** (including pain) **or signs** that could be associated with the **development of an intracranial abscess or meningitis**
* Semi-urgent referral to an ear, nose, and throat specialist should be arranged for people with a suspected cholesteatoma who do not have a serious complication.
63
For an auricular haematoma, discuss:
* What it is (being specific about where blood accumulates)
* Common cause
* Management
* Complications
* **Blood and serum accumulates between the cartilage and overlying perichondrium in the ear** *(most commonly affects helical rim of pinna)*
* **Trauma**
* **Cartilage is avascular** and gets it blood supply from perichondrium hence separation of these layers results in avascular necrosis of cartilage
* **Same day referral to ENT** for assessment & management
* Aspiration
* Incision & drainage *(shown to be superior)*
* Complication: **cauliflower ear deformity** *(get new asymmetrical cartilage development)*
64
For noise related hearing loss, discuss:
* What it is
* Risk factors
* Diagnoses to exclude
* Symptoms/how it presents
* Investigations
* Management
* Hearing loss due to damage to stereocilia due to excessive noise; can be a single loud event or damage over a period of time (generally sounds \>85dB)
* Risk factors:
* Occupational e.g. construction worker
* Recreational e.g. loud music
* Accidental e.g. blast injury, gunfire
* Not wearing appropriate ear defenders
* Diagnoses to exclude/other reasons for hearing loss:
* Impacted wax
* Acute ear infection
* Otitis media with effusion
* Symptoms/presentation:
* **Bilateral** hearing loss
* No features suggestive of infection, impaction, effusion etc...
* **Muffled speech**
* **Sensorineural** hearing loss
* Often accompanied by **high pitched tinnitus**
* **Hyperacusis**
* **Risk factors** present
* Investigations:
* Otoscopy: rule out other causes
* Weber's & Rinne's
* Audiometry
* Management:
* Irreversible therefore about trying to improve hearing and preventing further damage:
* Hearing aids
* Nosie protection e.g. foam ear plugs
* Education about how to protect ears
* Early detection
65
State some different types of hearing aids
66
State 3 different types of hearing implants
* Bone conduction implants
* Cochlear implants
* Brainstem implants
67
Briefly outline how bone conduction implants work
* External sound processor converts the sound picked up by its microphone into vibrations. The sound processor then transmits the vibrations through the bones of the skull to the cochlear of the inner ear. The inner ear then converts these (sound) vibrations into electrical signals that the brain interprets as sound.
* Bypasses external and middle ear
* Can be transcutaneous (magnet) or percutaneous (shown in image)
68
Briefly outline how cochlear implants work
* Sound picked up by microphone worn on or near ear
* Sound waves then converted into digital signal
* Wire delivers signals from to electrodes that have been surgically implanted in cochlear
* Electrode receives signal and creates and sends electric impulses directly to cochlear nerve
69
Briefly outline how brainstem implants work
Who are they often given to?
* Sound is picked up by microphones in the external speech processor and converts this into digital signals. Digital signals delivered to electrodes on cochlear nucleus producing stimulation that can be interpreted as sound in auditory cortex of brain
* Patients with neurofibromatosis type II (these pts often have bilateral acoustic neuromas; surgery for these may involve injury to CNVIII)
70
Briefly discuss the criteria for receiving cochlear implants
* Moderate to profound sensorineural hearing loss in both ears and did not get any benefit from hearing aids- give you 1 cochlear implant
* If you fulfil the above and are \<16yrs or have another sensory deficit- give you 2 cochlear implants
*\*\*\*Strict criteria as each implant is £60,000*
71
What must pts have in order to benefit from cochlear implants?
Good cochlear reserve (some surviving spiral ganglion neurones remaining in organ of Corti)
72
One of the risks of having cochlear implant surgery is increased risk of meningitis; hence, what should all patients have?
Up to date **pneumococcal vaccine**
