Ears Flashcards
Nerve distribution of ear
Upper later surface = auriculotemporal nerve (CN V3)
Lower lateral surface and medial = greater auricular nerve (C3)
Superior medial surface = lesser occipital nerve (C2/3)
External auditory meatus = auricular branch of CN X
Mx of ear lacerations
Clean the wound
Primary closure - ensure all exposed cartilage covered with skin
Plastic reconstructive surgery if significant skin loss
Mx of bites to ear
Gather hx to determine causative organism
Leave wound open
Irrigate and give abx
Mx of haematoma
Can disrupt blood supply to the cartilage -> vascular necrosis
Risk of associated deformity - cauliflower ear
Requires urgent drainage
Pressure dressing to prevent re-accumulation
Mx of tympanic membrane perforation
Can cause pain and conductive hearing loss
Often heals alone
- watch and wait
- advise not to get wet
If hasn’t resolved within 6 months consider myringoplasty
Mx of haemotypmanum
Blood in middle ear
- often associated with temporal bone fracture
Associated with conductive hearing loss
Self-resolving
Follow up to ensure no residual hearing loss - damage to ossicles
Define otitis externa
Diffuse inflammation of external ear canal
- may also involve pinna or tympanic membrane
Epidemiology of otitis externa
Life incidence of 10%
Most common 7-12 year old group
Common in warmer temps and humid conditions
Risk factors for otitis externa
External ear obstruction - cerumen blockage promotes retention of water/debris
High humidity
Local trauma
Skin disease
Diabetes
Immunocompromised
Prolonged use of topical anti-bacterial - inhibit normal flora
Pathophysiology of otitis externa
Most commonly bacterial infections - pseudomonas aeruginosa - staphylococcus aureus May be fungal - aspergillus Breakdown of skin integrity, insufficient cerumen production or blockage of ear canal can predispose to colonisation
Presentation of otitis externa
Rapid onset - within 48 hours Discharge from ear Painful ear - tragal tenderness Ear canal swelling and erythema Itchy ear
Ix for otitis externa
Pneumatic otoscopy - normal in otitis externa - abnormal in otitis media Tympanometry - normal Swab discharge for culture if resilient
Mx of otitis externa
Topical eardrops empirically - gentamicin - ciprofloxacin - dexamethasone Topical antifungals - acetic acid Pain mx with simple analgesia
Complications of otitis externa
Malignant otitis externa
- mainly seen in diabetes or immunocompromise
- infection spreads from soft tissue into the bone
- presents with chronic ear discharge, deep-seated severe ear pain, cranial nerve palsies
- granulation tissue in ear canal
- mx = IV ciprafloxacin as well as topical treatment
Define acute otitis media
Infection of middle ear space
Epidemiology of acute otitis media
> 80% of children present before 2 years
Peak incidence 6-18 months
Risk factors for acute otitis media
FHx Young age - shorter, more horizontal and poorly functioning eustachian tube Absence of breastfeeding Craniofacial abnormality - cleft palate Immunological deficiency
Pathophysiology of acute otitis media
Middle earl lined with respiratory (pseudostratified columnar) epithelium
- susceptible to infection with resp viruses
Creates effusion
Suppurative inflammatory response
Blockage in eustachian tube creates negative pressure in middle ear
- pressure against tympanic membrane leads to pain
Presentation of acute otitis media
Otalgia - children pull on ear Preceding URTI symptoms Bulging tympanic membrane - purulent middle ear effusion Myringitis - erythema of tympanic membrane Sleep disturbance Fever Decreased appetite Discharge CLINICAL DIAGNOSIS
Mx of acute otitis media
Analgesia - paracetamol/ibuprofen Delayed amoxicillin prescription - usually self-resolving Grommets - inserted to allow ventilation
Complications of acute otitis media
Bullous myringitis - visible on otoscopy - resolves with abx Tympanic membrane perforation - purulent otorrhoea - abx - usually heals rapidly Mastoiditis - infection extends into mastoid air cells
DDx of acute otitis media
Otitis media with effusion
- typically asymptomatic
- dull and retracted membrane
Myringitis - no symptoms associated with middle ear
Mastoiditis
- oedema, erythema and tenderness over mastoid process
Cholestaetoma
- normally presents with painless otorrhoea and hearing loss
Define chronic otitis media
Classified as active or inactive depending on whether discharge present
- active associated with chronic ear discharge and conductive hearing loss
Divided into squamous or mucosal
- squamous develops when keratinised squamous cells introduced into middle ear from retraction pocket or perforation
- mucosal develops when failure of tympanic membrane to heal after rupture
Presentation of chronic otitis media
Conductive hearing loss
Crusting in retraction pocket
Resistant to abx therapy
Mx of chronic otitis media
Squamous disease
- surgical clearance of cholesteatoma +/- mastoidectomy
- risk of recurrence if not totally cleared
Mucosal disease
- topical abx
- surgical repair of perforation
Risks of mastoid surgery
Facial nerve palsy Altered taste from damage to chorda typani CSF leak Tinnitus Vertigo Complete loss of hearing
Define otitis media with effusion
Fluid presence in middle ear with intact tympanic membrane
Epidemiology of otitis media with effusion
More common in children - shorter, more horizontal poorly functioning eustachian tube
Assess post-nasal space as tumour may cause eustachian tube dysfunction
Presentation of otitis media with effusion
No pain
Conductive hearing loss
Middle ear effusion - bulging tympanic membrane
Ix for otitis media with effusion
Otoscopy - bulging tympanic membrane - air under drum Pure tone audiogram - conductive hearing loss Tympanometry - type B flat compliance curve - no tympanic membrane movement
Mx of otitis media with effusion
Conservative
- settle in 3 months
Consider hearing aid
Grommet insertion +/- adenoidectomy in prolonged cases
Define oteosclerosis
Disease affecting ossicles in middle ear
Epidemiology of oteosclerosis
1-2% of population
F:M 2:1
Genetic and environmental components
Pathophysiology of oteosclerosis
Mature bone gradually replaces with woven bone
Symptoms develop as stapes footplate becomes fixed to oval window
Presentation of oteosclerosis
Progressive hearing loss
Tinnitus
Improved hearing in noisy surroundings
Pink hue on tympanic membrane
Ix for oteosclerosis
Tympanogram
- normal A trace
Pure tone audiogram
- conductive hearing loss
Mx of oteosclerosis
Hearing aid
Stapedectomy
Define vertigo
Hallucinations of movement
Associated with problems with vestibular system
Causes of vertigo
Central - stroke - migraine - neoplasms - demyelination - MS - drugs Peripheral - BPPV - Meniere's - vestibular neuronitis
Define benign paroxysmal positional vertigo
Vertigo occurring with particular head movements
- primary = idiopathic
- secondary = a/w head trauma, migraines, ischaemic processes
Epidemiology of BPPV
Peak incidence 50-70
More common in females
Risk factors for BPPV
Head trauma
Migraines
Inner ear surgery
Pathophysiology of BPPV
Crystals in semi-circular canals cause abnormal stimulation of hair cells
Presentation of BPPV
Episodic vertigo - provoked by specific positions - last less than 30 seconds Sudden onset intense vertigo Nausea Imbalance Lightheadedness
Ix for BPPV
Neuro and otological exam normal Dix-Hallpike test - patient sitting - turn head 45º - continue to support head - lower patient to 30º below horizontal - hold head for 30 secs and observe for nystagmus - return patient to seated position - positive if vertigo and nystagmus present
Mx of BPPV
Reassurance - most resolve spontaneously in 6 months Epley manoeuvre - patient sitting - rotate head to 45º to affected ear - lower patient to 30º below horizontal - maintain for 1-2 mins - observe for primary nystagmus - rotate head 180º to opposite ear - observe for secondary nystagmus - primary and secondary nystagmus in same direction indicates good response - maintain position for 30-60 seconds - sit patient up - should be no nystagmus or vertigo
Define Meniere’s disease
Auditory disease characterised by sudden, episodic onset of vertigo, low frequency hearing loss, low-frequency roaring tinnitus and sensation of fullness
Types of Meniere’s’ disease
Primary - idiopathic Secondary - head trauma - migraines - ischaemic processes
Epidemiology of Meniere’s disease
Disease of adulthood
- onset in 4th decade
Slightly higher female incidence
Evidence of genetic link
Risk factors for Meniere’s disease
Recurrent viral infection
Autoimmune disease
Presentation of Meniere’s disease
Recurrent episodes of vertigo - spinning sensation - lasts minutes to hours - a/w N+V Hearing loss - fluctuates - worsening during vertigo periods - chronic during later stages - unilateral Tinnitus - unilateral Aural fullness Drop attacks - sudden loss of balance without loss of consciousness Positive Romberg's test - sway when standing with feet together and eyes closed Positive fukunda stepping test - turn towards affected side when marching in place with eyes closed
Ix for Meniere’s disease
Pure-tone audiometry
- unilateral sensorineural hearing loss
- low frequency in early stages and high frequencies as disease progresses
Speech audiometry
- measures response to simple bisyllabic words
- compared to pure tone hearing to identify non-organic hearing loss
- no discrepancy
Tymapanometry
- normal
Mx of Meniere’s disease
Dietary changes - reduce salt, chocolate, alcohol and caffeine Thiazide diuretics Betahistine - symptomatic treatment of N/V during attaches Prochlorperazine - vestibular sedatives in acute attacks Dexamethasone - injected into middle ear Surgery - grommet insertion - endolymphatic sac decompression - surgical labyrinthectomy
Define vestibular neurontitis
Inflammation in the inner ear causes severe incapacitating vertigo lasting several days
- a/w N+V
- horizontal nystagmus during an attack
Mx of vestibular neuronitis
Symptomatic relief with vestibular sedatives during the acute attack IV fluids if recovered Cawthorne-Cooksey exercises to help with prolonged poor balance - look up then down - look left then right - bending neck forwards and backwards - turning head left and right - shrugging and rotating shoulders - walking up and down stairs
Features of hearing tests
Differentiate sensorineural hearing loss from conductive hearing loss
- sensorineural hearing loss otological emergency
Tuning fork tests
256 Hz or 512 Hz tuning fork used
Weber test
- knock tuning fork and place in centre of head
- should be equal in both ears
- if one ear sensioneural loss in other ear
Rinne test
- place tuning fork on mastoid for a few seconds then lateral to external ear meatus
- should be louder when held in air than bone - Rinne positive
- if louder over bone (negative) then conductive hearing loss
Uses of pure tone audiogram
Assess hearing thresholds at different frequencies
Used from ages 4 up
Tones played at different frequencies and quietest tone at each frequency recorded
Hertz on x axis, decibel on right
- lower decibel = quieter noise
- anything above 20 is normal
Air conduction and bone conduction measured
- air by headphones assess whole auditory pathway
- bone tested with bone conductor over mastoid bone
Findings of pure tone audiogram
Conductive
- pathology in middle or external ear
- audiogram has normal bone and reduced air conduction
Sensorineural
- pathology between cochlear and auditory of brain
- audiogram has reduced bone and air conduction thresholds - no air bone gap
Mixed
- air conduction worse than bone
- bone conduction worse than normal
Uses of tympanogram
Measures compliance of tympanic membrane at varying pressures
Probe inserted into external ear canal
Can be done at any age
Compliance measured along y axis and pressure on x axis
Findings of Tympanogram
Type A trace - normal - peak centred at 0 on x axis Type B - flat trace - suggest middle ear effusion or perforation - effusion has normal canal volume - perforation has large volume Type C - suggests Eustachian tube dysfunction Peak occurs at negative pressure
