ENT Flashcards
Webers test
How to: Strike tuning fork and place on centre of forehead.
Results;
* Normal = patient hears sound equally in both ears
* Sensorineural hearing loss = Sound is quieter in affected ear
* Conductive hearing loss = Sound is **louder **in affected ear
Rhinne’s test
How to: Strike tuning fork and place it flat on the mastoid process. Ask the pt to tell you when they stop hearing it and then remove it and hover it 1cm away from the ear.
Results;
* Normal = pt can hear the sound again once placed next to the ear
* Conductive hearing loss = Bone conduction is better than air conduction.
Causes of Sensorineural hearing loss
Sudden sensorineural hearing loss
Presbycusis
Noise exposure
Meniere’s disease
Labrynthitis
Acoustic neuroma
Neurological conditions
Infections (e.g meningitis)
Medications
Which medications cause sensorineural hearing loss
Loop diuretics
Gentamicin (&other aminoglycosides)
Cisplatin
Causes of conductive hearing loss
Ear wax / blockage
Infection - otitis media / otitis externa
Fluid in middle ear
Eustachian tube dysfunction
Perforated tympanic membrane
Otosclerosis
Cholesteatoma
Exostoses
Tumours
Presbycusis
Age related hearing loss - due to a loss of hair cells & neurons in the cochlea & atrophy of the stria vascularis
RF = old age / male / loud noise exposure / diabetes / HTN / ototoxic meds / smoking
Presentation;
* Typically affects **high pitched sounds first **
* Occurs gradually and symmetrically
* Often noticed by friends & family before patient
* **Tinnitus **
Invx = Gold standard = Audiometry which shows a sensorineural hearing loss pattern (worse at higher frequencies).
Management = optimise environment, give hearing aids or cochlea implants
Sudden sensorineural hearing loss (SSNHL)
Hearing loss over <72hours, unexlpained by other causes - an Otological emergency.
Causes;
* 90% idiopathic
* Infection e.g meningitis, mumps, HIV
* Meniere’s disease / MS / Migraine / Stroke
* Acoustic neuroma
* Ototoxic meds
* Gogan’s syndrome (rare autoimmune condition causing inflammation of eyes + inner ear)
Invx = Audiometry (loss of 30db in 3 consecutive frequencies)
MRI head / CT head to rule out stroke/acoustic neuroma/MS
management = immediate ENT referal (<24hrs) +/- steroids.
A loss of 30 decibels in 3 consecutive frequencies on audiometry testing is diagnostic of what condition?
Sudden sensorineural hearing loss
Labrynthitis
Inflammation of bony labrynth - including semicircular canals, vestibule + cochlea.
Usually attributed to a recently viral URTI.
Sx;
* Acute onset vertigo
* Hearing loss
* Tinnitus
* May have associated coryzal symptoms
Diagnosis = exclusion of other causes. Can do head impulse test (confirms peripheral cause of vertigo e.g labrynthitis)
Management = supportive care + short term symptomatic relief with Prochlorperazine/antihistamines
Meniere’s disease
Long term inner ear disorder caused by excess endolymph in the labrynth (endolymphatic hydrops) distrupting the sensory signals.
Sx;
* Typically age 40-50yrs
* Unilateral hearing loss - fluctuates at first then becomes permanent. Typically low pitched sounds first
* Vertigo - episodes lasting 20mins-hours. Not positional
* Tinnitus
* Unidirectional nystagmus may be seen during an acute attack
Diagnosis = Made by ENT specialist. Need audiology assesment.
Management;
- Prochlorperazine & Antihistamines
- Prophylaxis = betahistine (anti-vertigo)
Main difference between labrynthitis + vestibular neuritis
Both present with vertigo however vestibular Neuritis has No loss of hearing
Benign tumour of schwaan cells around the vestibulocochlear nerve
Acoustic neuroma (Vestibular schwwanoma)
Tumours typically occur at the cerebellopontine angle.
Features;
* Usually unilateral - if its bilateral then associated with neurofibromatosis type 2
* Hearing loss
* tinnitus
* Dizziness/imbalance
* Feeling of fullness in the ear
* Facial nerve palsy - if the tumour is large enough to compress the facial nerve - forehead is NOT spared as its a LMN lesion
Investigations - Audiometry confirms sensorineural hearing loss. MRI/CT can detect the tumour.
Management = Conservative. Surgery can be done to remove it / Radiotherapy to reduce growth
*Risks = Vestibulocochlear nerve injury / facial nerve injury
Eustachian tube dysfunction
Often related to viral URTI, Allergies or smoking.
Sx;
* Altered hearing
* Popping sensation in the ear
* sensation of fullness in the ear
* pain
* tinnitus
Symptoms typically get worse when the external air pressure changes e.g flying
Investigations = Otoscopy (to rule out other causes).
Tympanometry + audiometry can be of use.
Management = conservative manage
Valsalva manoevre (to inflate eustachian tube)
Decongestant nasal sprays / Otovent
Antihistamines / steroid nasal sprays if allergies
Surgical options = Adenoiectomy / grommets / Balloon dilation eustachian tuboplasty
Otosclerosis
= remodelling of the small bones in the inner ear leading to conductive hearing loss = autosomal dominant inheritence. Mainly affects the base of the stapes.
Sx;
* Usually presents <40yrs
* Hearing loss - affects low pitched sounds first
* Tinnitus
* pts may hear their voice sounding really loud compared to the environment
Invx = audiometry confirms conductive loss. Tympanometry shows reduced admittance of sound. High res CT can be done.
Management = hearing aids +/- Stapedectomy
Acute otitis media
Infection of the middle ear
Streptococcus pneumoniae most common
Sx;
* Ear pain
* Hearing loss in affected ear
* fever
* Coryzal symptoms
* May cause balance issues/vertigo
If the tympanic membrane perforates = discharge from ear (purulent otorrhoea)
Investigations;
* Otosopy shows a bulging tympanic membrane causing loss of light reflex. Also see opacification/erythema of the membrane.
Management = generally self limiting.
Antibiotics if indicated
Diagnostic criteria of acute otitis media
- acute onset of symptoms (otalgia/ear tugging)
- Presence of a middle ear effusion (bulging membrane, ottohorea)
- inflammation of the tympanic membrane
Indications for anitbiotics in otitis media
Symptoms lasting >4days or no improvement
Systemically unwell
immunocomprimised
Age <2yrs with bilateral otitis media
Perforation/discharge
Give 5-7 days amoxicillin (or clarith if pen allergic / erythromycin in pregnant allergic)
Complications of otitis media
Perforation
Chronic suppurative otitis media
Hearing loss
labrynthitis
mastoiditis
Meningitis
brain abscess
facial nerve palsy
Otitis externa
Inflammation of the skin in the external ear. A.K.A swimmers ear
Causes;
1. pseudomonas auerginosa (treat with gentamicin or ciprofloxcain)
2. Staph aureas
3. fungus - suspect this in pts with multiple recent Abx
Features = ear pain + discharge + itchiness + hearing loss. Otoscopy shows erythema of canal
Management;
1. Mild = Treat with acetic acid 2% (available OTC - use before and after swimming for prophylaxis)
2. Moderate = Topical antibiotic + steroid (e.g Neomycin + dexamethasone or Gentamicin + hydrocort) - *note these are ototoxic so do not give if perforation - refer to ENT *
3. Severe = Oral antibiotics (fluxoc or clarith) or admit to ENT