Otology Flashcards
What causes otitis externa?
P aeruginosa Staph aureus Aspergillus (black spores) Candida Risk factors: Cotton buds, water exposure, foreign bodies, adults/teens
What is seen upon examination of otitis externa?
Severe ear pain, discharge, itching, hearing loss Pinna tender to move Tragus tender Ear canal filled with discharge Ear canal swollen TM often not seen
What is the management for simple otitis externa?
Keep ears dry No poking Analgesia Topical antibiotics + steroid Eg gentisone HC, sofradex (don’t use cipro for OE as Pseudomonas becomes resistant quickly)
What is the management for complex otitis externa?
ENT referral Microsuction Pope wick and drops Admission IV antibioitcs (risk of pinna perichondritis) Aural toilet
What is necrotising otitis externa?
Severe unrelenting pain with canal granulation
Skull base osteomyelitis
Affects cranial nerves
Seen in immunocompromised
IV antibiotics for 6 weeks (some palsies may not recover)
What is pinna perichronidritis?
Pinna itself red and inflammed, lobule has no cartilage and therefore is spared. Consider autoimmune disorder. IVabx
What are the differential diagnoses for otitis externa?
Necrotising OE
Mastoiditis
Pinna perichondritis (lobule spared)
Pinna cellulitis (lobule inflamed)
What are the functions of the parts of the ear?
External: Sound amplification Protection of TM Cosmesis Middle: Sound/ energy transformer Inner: Hearing (Sensorineural)/ Balance
What is the scale for hearing loss severity?
Mild: 20-40 dB
Moderate: 40-70
Severe 70-90
Profound worse than 90
What are the results shown by tympanometry?
A: triangle, normal
B: flat, TM perf or effusion (OME)
C: wide triangle at start, negative pressure- poor eustachian function or effusion
As: tiny triangle, stiff- osteosclerosis
Ad: large triangle, dislocated- ossicular discontinuity
What is a pinna haematoma?
Collection of blood (distinct from bruise)
Blood between cartilage and perichondrium, leading to increased diffusion distance between cartilage and perichondrium and infection risk (perichondrium supplies cartilage with nutrients and O2)
Cartilage necrosis- cauliflower ear
Requires aspiration / drainage: ENT referral
What is a tympanoplasty / myringoplasty?
Repair of tympanic membrane
What are the types of mastoidectomies?
Cortical mastoidectomy. Removes just outer cortex. Used for cochlear implant, mastoiditis, combined approach tympanoplasty
Atticotomy (drills attic), atticoantrostomy (attic and antrum), modified radical mastoidectomy (drills out entire mastoid air cell system and creates a mastoid cavity); for cholesteatoma
Combined approach tympanoplasty. Type of cholesteatoma surgery where approach is both via ear canal and via a cortical mastoidectomy. It avoids a cavity, but recurrence rate is high so usually need several procedures
When is a bone anchored hearing aid used?
Ear atresia, and chronic ear discharge that stops use of a standard air-conducting hearing aid
What could an adult with glue ear signify?
Sign of a nasopharynx tumour
Commoner in south east asia
What are the signs of temporal bone fractures?
Bleeding ear CSF otorrhoea (test beta2 transferrin) Perf TM-canal laceration haemotympanum: blood behind TM Battle’s sign: mastoid bruise facial palsy
What is the management for temporal bone fractures?
Need CT
ENT management usually conservative. Steroids for FN palsy. Rarely FN exploration if immediate FN palsy. Management mostly directed by associated injuries
What is a cholesteatoma?
Squamous otitis media- lined sac in the mid ear
Most common aged 10-20
V=Cleft palate increases risk by 100 fold
When bursts releases osteoclatic enzymes:
Conductive hearing loss, SNHL, facial nerve palsy
Managed by surgical excision
In dry ear or frail patients- observation, aural toilet and ear drops
What is benign paroxysmal positional vertigo (BPPV)?
Abnormal presence of calcium carbonate crystals, usually in posterior semicircular canals. Spinning lasts seconds, usually on rolling over in bed. Very common
Tested with hallpike- dix
Treated with epley manouvre physiotherapy
What is meniere’s disease?
Triad of: spinning (hrs), worsening hearing associated with attack, tinnitus worse with attack. (aural fullness also common but not part of triad)
MRI: normal
What is the management for meniere’s disease?
MRI to exclude vestibular schwannoma Dietary: low salt, caffeine Medical: Betahistine, bendroflumethiazide Grommets Intratympanic gentamycin or steroid Pressure devices
What is tinnitus?
Perception of noise in absence of external stimulus Pulsatile: likely to find a cause. Look for bruits, anaemia, hyperthyridism; consider CT/MR angiogram (especially I unilateral – look for glomus jugulare tumour) Non pulsatile (Scan only if unilateral). Often associated with SNHL
What is the management for tinnitus?
Sound enrichment (TV on, music at night)
Hearing aids work well if associated hearing loss
Tinnitus masker plays noise into ear, which for some patients is less annoying than tinnitus
Tinnitus therapy: psychological techniques based on information giving and strategies to avoid stress response
Tell patient several options available, eventhough no easy cure
What are the causes of sudden SNHL?
Idiopathic (60%) Viral (labrynthitis) Tumours – (vestibular schwannoma)cystic expansion Temporal bone fractures Perilymph fistula- blast or barotrauma Menieres disease Ototoxic drugs (aminoglycoside, furosemide) CVA (hypoxic damage 8th nerve) Autoimmune Treated with steroids- narrow window Over 30db hearing loss in one frequency
What are the features of a cholesteatoma?
Foul-smelling, non-resolving discharge Conductive hearing loss Vertigo Facial nerve palsy Cerebeloopontine angle syndrome Attic retraction filled with squamous debris Attic aural polyps Discharging attic perforation
What are the complications of a cholesteatoma?
Facial palsy, vertigo, intracranial sepsis
What is the pathology of a cholesteatoma?
A negative pressure in the middle ear has its maximal effect on the pars flaccida of the tympanic membrane
causes it to balloon backwards forming a retraction pocket and trapping the outer layer of epithelium, this ball of squamous debris slowly enlarges and invariably becomes infected with pseudomonas
It tends to grow upwards into the attic region and backwards into the mastoid
Which structures are at risk of being eroded in cholesteatoma?
Ossicles- causing a conductive deafness of 50dB or more
Lateral semicircular canal- causing vertigo
Facial nerve- causing facial palsy
Labyrinth/cochlear- causing a sensorineural hearing loss (total or partial)
Roof of the middle ear- causing intracranial sepsis
Sigmoid sinus- causing it to thrombose