ENT Flashcards
What is the normal threshold for hearing?
-10dB to +15dB
What is the normal hearing range for humans?
20 to 20,000 Hz
What are the different severities of hearing loss?
Mild = 20-40dB
Moderate = 41-70dB
Severe = 71-95dB
Profound > 95dB
What are the categories of hearing loss?
Conductive
Sensorineural
Give examples of what causes a conductive hearing loss
Sound conduction is impeded through external ear, middle ear or both
Earwax Trauma to tympanic membrane Otitis Otosclerosis Cholesteatoma
Give examples of what causes a sensorineural hearing loss
Problem with the cochlea or the neural pathway to the auditory cortex
Presbyacusis (progressive, irreversible hearing loss of ageing)
MS
Acoustic neuroma
Occupational acoustic trauma
Ototoxicity - aminoglycosides, loop diuretics, quinine
Meniere’s disease
What test identifies the side of the hearing loss?
Weber’s test
- Conductive hearing loss = loudest in affected ear (blocked out background noises)
- Sensorineural hearing loss = quieter in affected ear
How can you distinguish between whether it is a conductive or sensorineural hearing loss?
Rinne’s test - if the tuning fork is perceived louder on the mastoid process, there is a conductive hearing loss
What is glue ear?
Otitis media with an effusion
The negative pressure in the Eustachian tube pulls fluid out of the lining of the middle ear
What usually causes otitis media?
Viral URTI - adenoid pads enlarge and block off eustachian tube
What is an important complication of otitis media? How does this occur and what is found on examination?
Mastoiditis
Infection can spread from the middle ear to form an abcess in the mastoid air spaces of the temporal bone.
This leads to post-auricular swelling pushing the auricle outwards and forwards
Mastoid tenderness will be present..
What is otosclerosis?
Autosomal dominant metabolic dysplasia of the ossicles
How does otosclerosis present?
Progressive bilateral conductive hearing loss (low frequencies)
Tinnitus
Quiet speech
What is Schwartze’s sign?
Red-blue oval window due to hyperaemia in otosclerosis
How do you treat otosclerosis?
Hearing aids
Stapedectomy
What usually causes otitis externa?
Swimmer’s ear
Trauma from ear buds
How does otitis externa present?
Otalgia (worse at night) Itchiness Lymphadenopathy of preauricular nodes Minimal discharge Tragal tenderness Conductive hearing loss if meatus becomes blocked by swelling/discharge
How do you treat otitis externa depending on the severity?
Mild to moderate
• Combined antibiotic/steroid drops - Gentamix (gentamicin + dexamethasone)
• Advise to keep ear dry for next 7-10 days
Severe
• Pope wicks - strip of ribbon gauze used for application of topical antibiotics (gentamicin) to enable deeper penetration
• Oral antibiotics if:
○ Cellulitis extending beyond external ear canal
○ If ear canal is so swollen that wick cannot be inserted
○ Immunocompromised patients including diabetics
What is cholesteatoma?
Locally erosive collection of epidermal/connective tissue in the middle ear
What causes primary cholesteatoma?
Chronic negative pressure due to a poorly functioning eustacian tube leads to dead skin cells getting trapped in the pars flacida
What causes secondary cholesteatoma?
Trauma
Chronic otitis media
How does cholesteatoma present?
Foul-smelling otorrhoea
Otalgia
Conductive hearing loss
Headache
What are risk factors for cholesteatoma?
Chronic otitis media
Trauma
What is the management for cholesteatoma?
Mastoid surgery to remove the sac of squamous debris
What do the otolith organs do?
Detect tilt and acceleration/deceleration
There are 2 otolith organs (utricle + saccule)
What do the semi-circular canals do?
Detect rotation
Control eye movements in the plane of the canal
What does dysfunction of semi-circular canals lead to?
Nystagmus
What causes benign paroxysmal positional vertigo?
Otolith detachment into semicircular canals (especially posterior ones)
Head movements set the particles in motion which gives spinning sensation until they settle
What investigation can you do for BPPV?
Dix-Hallpike test - vertical nystagmus on rapid depression of tilted head
How can you manage BPPV?
Usually self limiting
If persistent - Epley’s manehouvre
Rarely surgery eg vestibular nerve section
How can you distinguish between different causes of vertigo depending on how long they last?
Seconds to minutes = BPPV
Minutes to hours = Meniere’s disease
Hours to days = vestibular neuronitis
What is Meniere’s disease?
Disorder of the endolymph volume (labyrinthine fluid) with progressive distention of the labyrinthe
What is Meniere’s disease associated with?
Autoimmune diseases
Allergy
Metabolic disorders
Infection
What are the symptoms of Meniere’s disease?
Triad of:
- Vertigo
- Tinnitus
- Hearing loss (sensorineural)
Preceded by aural fullness
Last minutes to hours
+/- nystagmus
How can you treat Meniere’s disease?
Acute: Prochlorperazine - Buccastem 3mg/8hr bucally (vestibular sedative)
Prophylaxis:
Betahistine 16mg/8hr po
Limit salt intake
Surgical procedures:
Instillation of gentamicin via grommets
Labyrinthectomy (but causes total ipsilateral deafness)
Vestibular neurectomy
What is vestibular neuronitis/labyrinthitis?
aka acute vestibular failure
Isolated vestibular (CNVIII) neuropathy due to viral infection/herpes simplex reactivation
How does vestibular neuronitis/labyrinthitis present?
Sudden and severe vertigo that persists for several days but improves with time Nausea + vomiting Worsened with head movements Often following URTI Nystagmus away from affected side
Neuronitis - no hearing loss or tinnitus
Labyrinthitis - hearing loss + tinnitus
(NB cochlear + SCC = labyrinth)
How do you manage vestibular neuronitis/labyrinthitis?
Vestibular suppressants eg buccastem 3mg TDS po or PO cyclizine 50mg TDS
What does the facial nerve supply?
Mostly motor fibres to muscles of facial expression
Sensory fibres from anterior 2/3rd of tongue
What causes weakness of only the lower part of the face?
UMN lesion e.g. stroke, MS
Neurones in the CNVII nucleus supplying the upper face receive bilateral supranuclear innervation
What causes ipsilateral weakness of all facial expression muscles?
LMN lesion
- Bell’s palsy
- Trauma
- Otitis media
- Ramsay Hunt syndrome - herpes zoster
- Parotid tumour
What are the symptoms of Bell’s palsy?
Unilateral facial droop
Inability to close eye
Taste impairment
Hyperacusis - increased sensitivity to certain frequencies/volume ranges
How do you treat Bell’s palsy?
It is self-limiting
Can give prednisolone
80% make full recovery
What are nasal polyps associated with?
Asthma Hayfever Aspirin hypersensitivity Cystic fibrosis Sinusitis
Are nasal polyps usually unilateral or bilateral?
Bilateral = polyps Unilateral = malignancy
What defines acute and chronic sinusitis?
Acute = <4 weeks Chronic = >12 weeks
What causes acute and chronic sinusitis?
Acute
- S. pneumoniae
- H. influenzae type B
- Moraxella
Chronic
- Polyps
- Fungal infections
What are some risk factors for sinusitis
URTI Atopy Smoking Diabetes Swimming Dental problems CF
What are some complications of sinusitis?
Orbital cellulitis
Meningitis
Cerebral abscess
Osteomyelitis
How do you treat sinusitis?
Usually self limiting and resolve in 2.5 weeks
Nasal decongestants
Inhaled steroids e.g. beclometasone
Co-amoxiclav
What most commonly causes bacterial tonsillitis?
Beta-haemolytic streptococcus
What are the guidelines for when someone can have an elective tonsillectomy?
> 7 cases in last year
5 per year for 2 years
3 per year for 3 years
How do you treat tonsillitis?
Penicillin V if exudate present
What should you not give in pharyngitis?
Amoxicillin - if it were EBV, would cause a rash
What is quinsy?
Peritonsillar abscess
How does glandular fever present?
Cervical lymphadenopathy
Soft palate petechiae (rash on roof of mouth)
Exudative tonsils
Hepatosplenomegaly
How does epiglottitis present?
Odynophagia
Hoarse voice
Dyspnoea
Stridor
How do you manage epiglottitis?
Adrenaline nebulisers
IV dexamethasone
Intubate
Cricothyroidostomy
What are some causes of reactive lymph nodes?
Bacterial - TB, syphilis, s. aureus
Viral - URTI, EBV, CMV, HIV, herpes
Parasites - head lice, toxoplasmosis
Non-infective - sarcoidosis, SLE, amyloidosis
Children - cat scratch disease, Kawasaki disease
What malignancies most commonly cause enlarged lymph nodes?
Leukaemia - AML, CLL, ALL, (not CML)
Lymphoma
Mets from elsewhere
What are some congenital causes of neck lumps?
Thyroglossal cyst Dermoid cyst Pharyngeal pouch Cervical rib Laryngocoele
What is the criteria for 2 week wait referral for head/neck cancer?
- Unexplained ulceration in the oral cavity
- Persistent unexplained sore throat
- Persistent unexplained hoarseness
- Unexplained thyroid lump
How does acute otitis media present?
- Otalgia - might be pulling at ear
- Malaise
- Crying, poor feeding, restlessness
- Fever
- Vomiting •Coryza/rhinorrhoea
Perforation of TM often relieves pain - a child who is screaming and distressed may settle remarkably quickly then ear starts to discharge green pus
What causes pain in acute OM and how may this be relieved?
Bulging of tympanic membrane causes pain
Eases if drum perforates - associated with purulent discharge
What is the management of acute OM?
Analgesia
Acute OM resolves in 60% in 24hr with no abx
When should abx be considered in acute OM?
Immediate abx:
Systemically unwell
Immunocompromised
No improvement in symptoms in >4 days
Immediate or 2 day ‘delayed’ abx:
<3 months old
Perforation / discharge
<2yrs with bilateral OM
Which abx and dose are used in acute OM?
Amoxicillin 40mg/kg/day in 3 divided doses for 5 days
Erythromycin if penicillin allergic
What is chronic otitis media?
An ear with a tympanic membrane perforation in the setting of recurrent or chronic infections, associated with:
- Hearing loss
- Otorrhoea
- Fullness
- Otalgia
What are the 3 types of chronic otitis media?
1) Benign / inactive COM
2) Chronic serous OM
3) Chronic suppurative otitis media
What is benign / inactive COM?
Dry tympanic membrane perforation without active infection
How does chronic serous OM present?
Continuous serous drainage
Typically straw coloured
What is chronic suppurative OM?
Persistent purulent drainage through a perforated tympanic membrane
What is the management of COM?
Topical or systemic abx based on swab results Aural cleaning Water precautions Careful follow up Surgery
When is surgery considered in COM?
Aural cleaning and abx fail Persistent perforation / discharge Conductive hearing loss Chronic mastoiditis Cholesteatoma formation
What are the two surgical procedures offered in COM?
Myringoplasty = repair of tympanic membrane alone using a graft
Mastoidectomy = surgical repair of tympanic membrane and ossicles
How does a cholestaetoma form following chronic OM?
Prolonged low middle ear pressure allows for the development of a retraction pocket of the pars tensa or flaccida. As this enlarges, squamous cell epithelium builds up
What are some rare but serious complications of cholesteatoma?
Meningitis Cerebral abscess Hearing loss Mastoiditis Facial nerve dysfunction
Why is cholestatoma a misnomer?
It is not made of cholesterol nor is it a tumour
It is locally destructive around and beyond the pars flaccida from the release of lytic enzymes
How may a cholesteatoma present?
Foul discharge +/- deafness Headache Pain Facial paralysis Vertigo
These symptoms indicate impending CNS complications
What is the leading cause of hearing loss in children?
OM with effusion (OME) = glue ear
What is the management of OME?
Usually transient, mild and resolves spontaneously
50% with bilateral will resolve within 3 months
Observation for 3 months then reassess hearing
Auto-inflation of eustation tube via a balloon through the nose can help during this period
Surgery
What surgery can be offered in OME?
If worse after 3 months of persistent bilateral hearing loss, ventilation tubes can be inserted
Tympanostomy tube / grommets
What are some possible complications of grommet insertion?
Infections and tympanosclerosis
What advise is given regarding grommets?
Okay to swim post op but avoid forcing water into the middle ear by diving
Use ear plugs
Grommets extrude after 3-12 months, recheck hearing at this point
Approx 25% need reinsertion
Very rarely, a small perforation remains after grommets come out which may require surgery
When is systemic treatment indicated for otitis externa? What may be given?
Immunosuppression
DM
Severe OE with cellulitis of face and neck
Topical administartion not possibly eg severe oedema
Oral ciprofloxacin
What is necrotising inflammation of the external auditory canal?
Malignant otitis externa
Rare life threatening infection of the external ear that can lead to temporal bone destruction and base of skull osteomyelitis
What is the causative organism of malignant OE?
Pseudomonas aeruginosa (95%)
How does malignant OE present?
Severe ear pain
Red and swollen periauricular soft tissue
Otorrhea
Conductive hearing loss
What are some complications of malignant OE?
Facial nerve palsy
Osteomyelitis of skull base leading to extradural abscess, venous sinus thrombosis, paralysis of other cranial nerves
How should malignant OE be investigated?
CT for bone destruction
MRI for intracranial extension eg venous sinus thrombosis, cranial abscess
Biopsy to distinguish from a tumour
What is the management of malignant OE?
Prompt IV abx for several weeks
1st line ciprofloxacin
2nd line other antipseudomonals eg piperacillin-taxobactam
Surgical debridement
High mortality
What is cerumen?
Natural protective wax produced and secreted in outer third of the canal
How may excess impacted ear wax present?
Dulled hearing
Feeling of fullness
+/- tinnitus
How is excess ear wax removed?
Ear drops alone can clear the wax - Drops should be inserted 2-3 times each day for 3-7 days
if not…
Suction under direct vision using a microscope
OR
Irrigation (syringing) after softening with olive oil
When should an ear not be irrigated?
Perforated TM
Grommets in place or within 1.5yrs
Cleft palate
After mastoid surgery
Describe the Epley manoeuvre
Follow these steps if the problem is with your right ear:
Start by sitting on a bed.
Turn your head 45 degrees to the right.
Quickly lie back, keeping your head turned. Your shoulders should now be on the pillow, and your head should be reclined. Wait 30 seconds.
Turn your head 90 degrees to the left, without raising it. Your head will now be looking 45 degrees to the left. Wait another 30 seconds.
Turn your head and body another 90 degrees to the left, into the bed. Wait another 30 seconds.
Sit up on the left side.
How may conductive hearing loss present?
Hearing improves in noisy environments
Volume of voice remains normal because inner ear and auditory nerve are intact
Sound is not normally distorted
Features of external auditory canal pathology present eg cerumen impaction
How may sensorineural hearing loss present?
Hearing worsens in noisy environments
Volume of voice may be loud because nerve transmissions are impaired
Tend to lose higher frequencies preferentially = sound may be distorted
Often associated with tinnitus
What is the most common cause of sensorineural hearing loss?
Presbycusis
What is presbycusis? Which frequency is lost?
Progressive bilateral and irreversible damage of the hair cells of the organ of corti that impairs high frequency hearing
What is the management of presbycusis?
Hearing aids
Cochlear implants
How do hearing aids work?
Devices that amplify sound to help with conductive and sensorineural hearing loss
How do cochlear implants work?
When are they indicated?
Prosthetic devices that are surgically implaned and function by electrical stimulation of CN VIII
Indicated if hearing aid treatment was unsuccessful
Auditory nerve and auditory system must be intact
What is the most common way to assess hearing?
Pure tone audiometry
How does pure tone audiometry work?
Headphones deliver sounds over frequencies 250-8000 Hz
Initially played above hearing threshold then is decreased in 10dB intervals until no longer heard
Then increase in 5dB until a 50% response rate is obtained
What is the most common cause of otalgia (ear pain)?
50% non otological
List five common causes of otalgia
Barotrauma Eustachian tube dysfunction FB Otits externa Otitis media
What does a pt with otalgia with a recent scuba diving hx?
Barotrauma
How can barotrauma be prevented?
Topical decongestants
Autoinflation
List come uncommon causes of otalgia
Cellulitis of auricle eg following insect bite Cholesteatoma Wegener granulomatosis - granulomatosis Malignant OE Mastoiditis Ramsay Hunt syndrome - Herpes zoster oticis Relapsing polychondritis Trauma Tumours Infected cyst Viral myringitis
How may ramsay hunt syndrome present?
Pain can be present before lesions develop
+/- hearing loss, vertigo, tinnitis
Vesicular rash on auricle of ear canal with possibly palsy of CNVII
How does relapsing polychondritis present? Is the ear lobe involved?
Recurrent swelling of the auricle
Hearing loss
Earlobe not involved as it has no carticale
How would wegener granulomatosis present?
Arthralgia Hearing loss Myalgias Oral ulcers Otorrhea Rhinorrhea
What should be tested for in wegeners granulomatosis?
Antineutrophil cytoplasmic autoantibodies
What are some secondary causes of otaligia?
Bell palsy Carotidynia Cervical adenopathy Tumours Neuralgias Sinusitis TMJ syndrome
How may Bell palsy present?
Retroauricular pain that is less severe than with Ramsay Hunt syndrome
