Week 2 Flashcards
What is conductive hearing loss
Hearing loss due to sound conduction being blocked / impaired
pathology is in the external or middle ear
What is sensorineural hearing loss
Hearing loss due to damage to the neural pathway
Pathology is in the inner ear / brain / nerves
What are the causes of conductive hearing loss
Otitis media
Otitis externa
Otosclerosis
Perforation of the tympanic membrane
Choleastoma
Glue ear
What will the audiometry for conductive hearing loss be like
Difference in air conduction level and bone conduction level where bone > air
Carhart’s notch in otosclerosis
What will the audiometry for sensorineural hearing loss be like
Significant drop in hearing in all frequencies
No difference in air conduction and bone conduction
What clinical examinations can be done to differentiate between conductive and sensorineural hearing loss
Rinne’s test
Weber’s test
What is otitis externa
Inflammation of the external acoustic canal
Otitis externa is most common in
Children and young adults
Risk factors of otitis externa
Swimmers
Humid air
Obstruction of the external acoustic canal
Eczema
Psoriasis
What can cause obstruction of the external acoustic canal
Use of cotton buds
Foreign bodies
Main cause of otitis externa
Bacterial infection
Causes of otitis externa
Bacteria
Fungal
Eczema
What skin conditions may lead to otitis externa
Contact dermatitis
Seborrheic dermatitis
What is contact dermatitis
Dermatological symptoms (pruritus, rash) due to direct contact with a substance
What bacterial pathogens are the main cause of otitis externa
S aureus
Pseudomonas aeruginosa
What fungal pathogens can cause otitis externa
Candida
Aspergillus
Symptoms of otitis externa
Otalgia
Discharge
Itchiness
Swelling
Erythema
Hearing loss (In severe cases)
Management of mild to moderate otitis externa
Analgesia
Topical antibiotics +/- topical steroids
Avoid swimming and keep ears dry
Management of severe otitis externa
Use Pope wicks to apply topical antibiotics +/- steroids deeper
What should you be aware of in immunocompromised patients with otitis externa
Malignant otitis externa
Are oral antibiotics used for otitis externa
Not usually used
Indications for used of oral antibiotics for otitis externa
Ear canal is occluded by swelling and cannot be treated by Pope wicks
Immunocompromised patients
Infection spreading beyond the external ear
What is malignant otitis externa
Invasive infection of the mastoid and temporal bones surrounding the ear canal
Malignant otitis externa is most commonly caused by
Pseudomonas aeruginosa
What is otitis media
Inflammation of the middle ear
Otitis media is most common in
Children especially after URTI
Why may otitis media occur after URTI
Pathogens from URTI made their way up to the middle ear through Eustachian tube
Why are children more susceptible to otitis media after URTI
Children’s Eustachian tube is shorter and less angled, making it easier for pathogens to enter the middle ear cavity
Children have immature immune system
Otitis media is mostly commonly caused by
Bacteria
Virus
What are the bacteria responsible for otitis media
Streptococcus pneumoniae
H influenza
Which bacteria is the most common cause of Otitis media
Streptococcus pneumonia
What viruses are responsible for Otitis media
RSV
Rhinovirus
Adenovirus
Influenza virus
Why may children and infants present otitis media differently from adults
Because they cannot express well
Symptoms of otitis media in infants and children
Fever
Irritability
Difficulty feeding
Holding / tugging ear
Symptoms of otitis media in adults
Fever
otalgia
Hearing loss
Investigations for otitis media
Otoscopy
What may be seen through otoscope in a patient with otitis media
Erythematous tympanic membrane
Swelling
Bulging tympanic membrane
Perforation of tympanic membrane
Dilated vessels on tympanic membrane
What causes bulging of tympanic membrane
Pus filled in the middle ear cavity
Complications of otitis media
Facial nerve palsy
Mastoiditis
Meningitis
Labrynthitis
Brain abscess
Sigmoid sinus thrombosis
Patients with facial nerve palsy can present differently. Why is that
Because different parts of the nerve are affected - it can be upper or lower motor neurone that is affected
Difference in presentation between upper ad lower motor neurone facial palsy
If upper motor neurone is affected - forehead structures are not affected - furrowing of eyebrows, blinking, closing eyes are not affected
If lower motor neurone is affected - all facial muscles are weak
How does otitis media cause mastoiditis
Infection may have spread to the mastoid air cells via mastoid antrum which is an opening in posterior wall of middle ear cavity
What are the signs of mastoiditis
Postauricular swelling
Auricle pushed outwards and forwards
Mastoiditis tends to affect
children
What is labrynthitis
Inflammation of the semicircular canals
What can labrynthitis cause
Vertigo
Loss of balance
Nausea
Vomiting
Management for acute otitis media
Generally self limiting
Analgesia - paracetamol / ibuprofen
Consider antibiotics and admitting the patients under certain conditions
When should you consider delayed prescription of antibiotics (i.e. wait and see before giving) to patients with otitis media
If symptoms don’t improve after 3 or 4 days
When should you consider immediate prescription of antibiotics to patients with otitis media
If systemically very unwell
If at high risk of complications
When should you admit a patient with acute otitis media
Children under 3 months with > 38 temperatuer
Children with suspected complications
What is chronic otitis media
A group of conditions that causes inflammation and infection for 3 months or more
What conditions are included in chronic otitis media
Otitis media + effusion (glue ear)
Cholesteatoma
Perforation
What is glue ear
Inflammation of the middle ear with accumulation of fluid without the signs and symptoms of acute otitis media
Is glue ear an infection
No, it is not an infection
Cause of glue ear
Eustachian tube dysfunction - fluid builds up due to blocked Eustachian tube unable to drain it from middle ear cavity to the nasal cavity
Glue ear can occur after certain conditions
Recurrent URTI
Recurrent otitis media
Frequent nasal obstruction
Risk factors for glue ear
Day care
Bottle fed (poor immunity)
Smoking household
Genetic mucociliary disorders (Cystic fibrosis, Primary ciliary dysfunction)
Genetic craniofacial disorders (Down syndrome)
Symptoms of glue ear in children
Learning or language difficulties
Listening to loud TV or devices
Talk loudly
Lack of concentration
Need to repeat things for them
Ear rubbing
Investigations for glue ear
Otoscopy
Audiometry / Weber’s / Rinne’s
What would be seen on otoscope for glue ear
Visible fluid or air bubbles due to fluid
Cloudy tympanic membrane
Immobile tympanic membrane
Retraction of the tympanic membrane
Management for glue ear
Generally resolves by itself after 3 months
Review at 3 months
Only perform surgery under certain conditions
Hearing aid if surgery is not appropriate
When is surgery for glue ear considered
If it doesn’t resolve after 3 months
If the child is having learning / language difficulties
If the child is having behavioural problems
Surgical options for glue ear
Grommet
Grommet + adenoidectomy
Hearing aid instead of surgery is mostly offered to
Patients with down syndrome because complications from grommet is common
What are the complications of grommets
Infection
Perforation
Falls out too early / doesn’t fall out
What can cause perforated tympanic membrane
After acute otitis media
Trauma - sudden negative pressure
Insertion of foreign objects
Perforation of the tympanic membrane is most common in
Children after acute otitis media
Symptoms of perforation
Sudden pain
Bleeding
Tinnitus
Hearing loss
Management of perforation
Generally heals by itself taking up to a year
Keep ears dry to prevent infection
Surgery if there is recurrent discharge
What is cholesteatoma
Growth of keratinising squamous epithelium in the middle ear and invading other areas such as mastoid bone
Causes of cholesteatoma
Perforation
Retraction
How does retraction of tympanic membrane cause cholesteatoma
Negative pressure pulls the tympanic membrane inwards (retraction) and create a pocket of dead epithelial cells. The pocket becomes infected / grow and erode other bones and surrounding structures
Most common location of cholesteatoma
Anterosuperior quadrant of tympanic membrane
Symptoms of cholesteatoma
Discharge
Hearing loss
Vertigo
Facial nerve palsy
Investigation for cholesteatoma
Otoscopy
Audiometry / Rinne / Weber
What will you see on otoscope in a patient with cholesteatoma
Retraction or perforation of the tympanic membrane
White material usually at anterosuperior quadrant
What is otosclerosis
Progressive fixation of stapes footplate so it doesn’t function as a piston onto the cochlea
= no movement of perilymph
= no movement of hair cells
What does otosclerosis cause
Progressive conductive hearing loss
Cause of otosclerosis
Familial - autosomal dominant condition
Management of otosclerosis
Hearing aids
Stapedectomy
What are the causes of sensorineural hearing loss
Presbycusis
Noise induced
Drug induced
Vestibular Schwannoma
Meniere’s
Trauma
What is presbycusis
Degenerative condition of the cochlea causing progressive sensorineural hearing loss
What causes presbycusis
Loss of hair cells
Loss of ganglion cells
Strial atrophy
What is strial vascularis
Capillary loop in in cochlear duct producing endolymph for scala media
Risk factors for presbycusis
Elderly
High levels of noise exposure
Presbycusis is most common in
Elderly
Management of presbycusis
High frequency hearing aid
What causes noise induced hearing loss
High levels of industrial noises
Characteristic of noise included hearing loss in audiometry
Dip at 4000Hz
What are the drugs that can cause drug induced hearing loss
Gentamicin
Cisplatin
Vincristine
Overdose aspirin and NSAID
What is Vestibular Schwannoma
Benign subarachnoid tumour arising from the vestibular portion of CN VIII in the internal acoustic meatus
What is CN VIII
vestibulocochlear nerve
Symptoms fo vestibular schwannoma
Progressive unilateral hearing loss
Progressive tinnitus (only on affected side)
Loss of balance
Facial numbness
Progressive episodes of dizziness
Headaches
Management fo vestibular schwannoma
If small - monitor every 6 months
If big - surgery
What causes facial numbness in vestibular schwannoma
Compression of trigeminal nerve
What is Ménière’s disease
Idiopathic dilatation of the endolymphatic spaces of membranous labyrinth
What may be a possible reason for Ménière’s disease
Due to increase in endolymphatic pressure caused by dysfunctioning of sodium channels
Symptoms of Ménière’s disease
Episodes of vertigo - dizziness, nausea, vomiting
Unilateral hearing loss and tinnitus during the episodes of vertigo
Aural fullness on the affected side
How long does each vertigo episode last in Meniere’s disease
Hours
The vertigo in Ménière’s disease is in which direction
Rotational vertigo
Investigations for Meniere’s
Audiometry
What is a pattern on audiometry shown in Meniere’s
Low frequency hearing loss
Management for Ménière’s disease
Betahistine for prophylaxis
Prochlorperazine for acute attacks
Reduce salt intake
Avoid chocolate, caffeine, stress
What is vertigo
A hallucination of movement- spinning, falling ..etc
What is dizziness
A non-specific term that may include vertigo, disequilibrium, pre syncope ..etc
Causes of vertigo
Cardiac
Neurological
Vestibular
Visual
Ototoxicity
What are the vestibular causes of vertigo
BPPV
Meniere’s
Vestibular neuronitis
Acute labyrinthitis
Ototoxicity
How do you differentiate between the different types of vertigo
Through history
E.g. If present with palpitations - probably cardiac
If present with visual disturbance - probably visual
If present with paraesthesia, weakness, speech problems - probably neurological
How do you differentiate between the different otogenic causes of vertigo
By duration of episodes and associated symptoms
What is the most common otogenic cause of vertigo
BPPV
What is the vestibulo cochlear reflex
When your head turns one way, your eyes will turn to the opposite way to stabilise your gaze during head movement
What causes nystagmus
Defects in vestibulo cochlear reflex
When What causes BPPV
Otocania (otoliths) becomes dislodged into the semicircular canals
This causes the otocania to roll around freely in those semircular canals during head movements
As it rolls, hair cells are triggered
So inappropriate signals are sent
When can vertigo in BPPV occur -when they
Looking up
Rolling in bed
Getting out of bed
Bend forwards
bend backwards
Symptoms BPPV
Vertigo
Nausea and vomiting
no auditory symptoms
How long does vertigo of BPPV usually last
30 seconds to 1 minute
Investigations for BPPV
Dix Hallpike manoeuvre
What is a positive Dix Hallpike manoeuvre
Torsional geotropic nystagmus
Vertical nystagmus
Nausea and vomiting
Management of BPPV
Epley manoeuvre
Selmont manoeuvre
Brandt Daroff exercises - 10 reps for 3 time a day
