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Flashcards in The Middle Ear Deck (38)
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1
Q

What does the middle ear consist of?

A

Ossicles - MIS bones - Malleus, Incus, Stapes

Eustachian tube

Between tympanic membrane and oval window

2
Q

What is otosclerosis?

A

Increased boney turnover leading to sclerosis and fixation of stapes to oval window

May eventually affect bone structures of cochlea

3
Q

What are some causes of otosclerosis?

A

Genetic - autosomal dominant

Environmental factors - hormones in pregnancy

4
Q

Who does otosclerosis affect?

A

Females
15-35yo
Symptomatic in about 1-2% of population

5
Q

How does otosclerosis present?

A

Progressive hearing loss (bilateral in 70%) - worse for low tones (male voices harder to determine)
Tinnitus
Improved hearing in noisy surroundings - early stage
Patients speak quietly - enhanced bone conduction so their own voice sounds loud
Family history
Normal examination but pos. schwartze sign

6
Q

What is Schwartze sign?

A

Pink hue to tympanic membrane (vascular hyperaemia of immature bone)

7
Q

How would you investigate otosclerosis?

A

Tympanogram - normal type A trace

Pure tone audiogram - conductive hearing loss, characteristic Carhart notch at 2kHz

CT

8
Q

How is otosclerosis managed?

A

Conservative - hearing aid

Surgery - Stapedectomy

9
Q

What does the middle ear have important close relations to?

A

Internal carotid artery
Internal Jugular Vein
Facial Nerve

10
Q

What muscles are present in the middle ear? What is their function?

A

Tensor tympani - attach to handle of malleus - CNV3

Nerve to stapedius - attach to stapes - CN7

Contract in response to loud noises to inhibit vibration and reduce sound transmission

11
Q

What are the types of otitis media?

A

Acute OM - acute inflammation of the middle ear

Acute suppurative OM - presence of pus in middle ear

Otitis media with effusion - Chronic inflammation of the middle ear with presence of glue like effusion behind tympanic membrane

Chronic suppurative OM - long standing pus in middle ear - often associated with perforated TM

12
Q

What are the risk factors associated with acute otitis media?

A
Smoker/smoking in household
Bottle fed
Craniofacial abnormality - e.g. Down's
Allergies
Chronic Sinusitis
13
Q

How does acute otitis media appear on examination?

A

Red, yellow or cloudy
Bulging disk
Air fluid level visible
Discharge in external acoustic meatus due to perforation

14
Q

What is the pathophysiology of acute otitis media?

A

Organism reach middle ear from nasopharynx via the eustachian tube - flatter in children

70% bacterial - H Influenzae/S Pneumoniae
Viral - RSV or rhinovirus

15
Q

How does acute otitis media present?

A
Pain - children tug at ear
Hearing loss
Fever
Malaise
Crying, poor feed, irritable
Coryza/co-incidental bronchiolitis
16
Q

How is acute otitis media managed?

A

Paracetamol/ibuprofen + warm compress

Delayed prescription of amoxicillin 4 days

If <3months - immediate Abx is systemically unwell or at risk of complications

17
Q

What differentials are considered for acute otitis media?

A

Otits externa/URTI

Dental problem

Cardiac issue - referred pain from MI

Temporomandibular Joint Dysfunction

Cranial Nerve Palsy

Headaches

18
Q

What complications can arise from acute otitis media?

A

TM perforation

Progress to chronic suppurative otitis media

Meningitis/Sepsis

Facial nerve palsy

Febrile convulsions

Mastoiditis

19
Q

What is mastoiditis?

A

Inflammation of mastoid periosteum and air cells following spread of acute otitis media

20
Q

What is glue ear?

A

Otitis Media with Effusion - fluid in the middle ear with chronic inflammation

21
Q

How common is glue ear?

A

80% of children have an episode by the age of 10

22
Q

When does glue ear normally occur?

A

Following acute OM

More likely if underlying Eustachian tube dysfunction, adenoidal hypertrophy or infection

23
Q

How does glue ear present?

A

Hearing loss - tv volume high, poor concentration, impaired speech development

Intermittent ear pain, fullness and popping

PMG of recurrent ear infections and URTI

24
Q

How would the tympanic membrane appear with glue ear?

A

Opacification

Loss of light reflex

Indrawn eardrum

Fluid level

25
Q

How would you investigate and manage glue ear?

A

90% self-resolve so just require ear hygiene advice

3 months - refer to audiology - may show conductive hearing loss

Repeat hearing test after another 3 months, if still showing hearing loss then refer to ENT

26
Q

When is grommets (+- adenoidectomy) considered for glue ear?

A

Bilateral otitis media with effusion (OME) >3 months

> 25dB loss in good ear

OME cause severe developmental problems

27
Q

What surgical complications can arise from grommet insertion +- adenoidectomy?

A

Tympanosclerosis
Infection
Chronic perforation

28
Q

What is chronic suppurative otitis media?

A

Chronic pussy inflammation of the middle ear and mastoid accompanied by tympanic membrane perforation +- cholesteatoma

29
Q

What is the difference between safe and unsafe chronic suppurative otitis media?

A

Safe - central (tubotympanic perforation), no cholesteatoma

Unsafe - top (atticoantral perforation) - cholesteatoma

30
Q

How does Chronic Suppurative Otitis Media present?

A

> 2 weeks otorrhoea
TM perforation
Conductive hearing loss

If otalgia, fever or vertigo req. URGENT assessment!

31
Q

What may be seen on examination with Chronic Suppurative Otitis Media?

A

Discharge - serous, purulent or cheese like

Granulation tissue within external acoustic meatus/middle ear space

Middle ear mucosa oedematous and red

32
Q

How is Chronic Suppurative Otitis Media managed?

A

Routine ENT assessment:

  • micro suction to visualise TM and remove debris
  • topical ahminoglycosides (ototoxic but benefit outweigh risk)
  • topical steroids - reduce granulation tissue
  • Surgery - if unsafe or persistent despite other treatment
33
Q

What complications can occur due to chronic suppurative otitis media?

A

Facial nerve palsy
Meningitis
Labyrinthitis
Abscess

Long term - hearing loss & tympanosclerosis

34
Q

What is a cholesteatoma?

A

Keratinising squamous epithelium within the middle ear following tympanic membrane retraction

35
Q

Why should otitis media with effusion in adults be treated as suspicious?

A

Very rare

5% have head and neck cancer

36
Q

What are the other risk factors for otitis media with effusion in adults?

A

Paranasal sinusitis - Eustachian tube inflammation and dysfunction

Severe nasal septum deviation - block airway

Large tonsils - block ET

Barotrauma

37
Q

How should otitis media with effusion in adults be managed?

A

Urgent ENT referral

If no underlying cause - treat as in children: self resolve/grommets if persistent or >25dB hearing loss

38
Q

What complications are associated with stapedectomy?

A
Sensorineural hearing loss
Tinnitus
Perforated TM
Facial nerve injury
Taste disturbance