Otology Flashcards
What is AOM? How is it treated?
Infection and inflammation of the Middle Ear. Usually have pain (due to P on TM) that stops when discharge appears in the ear canal due to rupture of the TM. Systemic signs are common e.g. Fever. Common in kids that usually follows URTI that spreads via Eustacian Tube to middle Ear. Pus forms and TM bulges out.
Perforation due to blanching of blood supply at point of highest P and avascular necrosis.
PC: pain, systemic upset + fever, ottorhoea/ blood, hearing loss
Common causes: H influenzae, Strep pneumoniae
Complications can include- Pus drains to Mastoid Air cells via aditus causing Mastoiditis, Mastoid Abscess, Intracranial Abscess, Meningitis, Death.
Can be viral (most common therefore wait 24-48h before prescribe Abx)- antipyrexials, analgesia.
Bacterial if symptoms present 48h after presentation. Give Oral Abx: co-amoxiclav, keep ear dry if perf, simple analgesia. Myringotomy if severe complications/ fails to resolve.
Best scenario: Oral Abx resolves AOM/ rupture of TM to allow pus to drain.
What is OME? What are the tx options?
Glue Ear due to Eustacian Tube Dysfunction/ Blockage/ Cleft Palate. May see bubbles and grey fluid behind TM.
ET is blocked which creates sealed chamber of the Middle Ear. ET can be blocked by enlarged adenoid at back of nasal cavity/ mucosa oedema in post nasal space. As kids grow, these involute and grow away and the nasal cavity enlarges.
The resp epithelium of middle ear absorb O2 and N2 from air and eventually the PP in middle ear falls below that of the atmosphere. This results in negative PP in the middle ear and causes the release of fluid from the resp epithelium into middle ear. Initially this is yellowy and watery but as it remains in the middle ear, the water is absorbed from the fluid by the resp epithelium leaving a sticky grey fluid.
Sterile fluid collects in Middle Ear.
Glue ear fluctuates
In adults with unilateral must exclude carcinoma of postnasal space
Management options:
- Do nothing (bc will resolve eventually on own and can be manageable for some)
- Conservative management- monitoring
- Hearing aids bc hearing loss is the most common PC / developmental delay due to hearing loss
- Grommets to reduce the negative PP of the middle ear and the fluid will be naturally reabsorbed.
See flat tympanogram due to negative P behind TM
What is Otitis Externa? How is it managed?
Infection of EAM. Very painful due to inflammation in fixed bony cavity.
Can also be caused by eczema/ psoriasis.
Treated with Abx drops, oral have no effect.
How would you differentiate OM, OE, Cholesteatoma in the history?
Pain- AOM is very painful until TM perforates after which pain reduces/ ceases. Pain then discharge.
- Cholesteatoma: Painless discharge (often smelly). Skin cells in pocket are necrotic ie dead so no nerve supply.
- OE: Painful always (inflammation in fixed bony canal) and discharge at the same time.
What is Chronic Suppurative Otitis Media? (CSOM)
middle ear mucosa becomes repeatly infected leading to micro abscesses and inflammatory cell infiltrates and hypertrophy and hypersecretory resp mucosa. If perforation present chronic odourless discharge (pus) aka ottorhoea. Conductive hearing loss is common.
Repeated infections can lead to poor repair of TM perforation. Some patients with CSOM are at risk of developing Cholesteatoma or intracranial sepsis.
Tx: Myringoplasty if confined to middle ear/ Mastoidectomy if mastoid air cells also involved+ Myringoplasty.
What is myringosclerosis?
calcification of collagenous scar tissue originating from previous infection/ trauma e.g. TM perf. It may cause no symptoms if confined to TM or result in deafness due to calcification of ossicular chain.
RF for tympanosclerosis- grommets, high LDL, acute/ chronic OM.
Chalky white patches seen on inspection of TM.
What functions should you test if someone presents with inner ear pathology? Think about connections broadly.
- Dizziness, vertigo
- Cerebellar function
- Vision
- Nystagmus
- Facial n palsy
ADD TO
What is a cholesteatoma? What are the other ddx for it’s PC?
Pocket of necrotic skin cells that contains autolytic enzymes that degrade surrounding tissue and bone. Can be acquired due to a retraction pocket in TM following perf of TM or -ve P in Middle Ear encouraging retraction of pars flaccida. Congenital- due to ectodermal cells (skin) stuck where mesoderm/ endoderm (resp epithelium) found and the subsequent prolif of these cells. It is a benign and slow growing condition however can cause considerable hearing loss due to erosion of ossicles and other consequences:
1. vertigo due to erosion of semicircular canals
2. facial palsy due to erosion of CNVII in the facial n canal
3. sensorineural deafness due to erosion of cochlea
4. sepsis/ intracerebral abscess due to erosion of tegmen
5. thrombosis of sigmoid sinus
ddx- CSOM chronic suppurative Otitis Media.
What is a cholesteatoma? What are the other ddx for it’s PC? What are the complications?
Pocket of accumulating necrotic squamous skin cells that contains autolytic enzymes that degrade surrounding tissue and bone. Likely to follow retraction of TM e.g. due to Glue Ear. Discharge is due to bacteria hanging out in the pocket. It is a benign and slow growing condition however can cause considerable hearing loss due to erosion of ossicles and other consequences:
1. vertigo due to erosion of semicircular canals
2. facial palsy due to erosion of CNVII in the facial n canal
3. sensorineural deafness due to erosion of cochlea
4. sepsis/ intracerebral abscess due to erosion of tegmen
5. thrombosis of sigmoid sinus
ddx- CSOM chronic suppurative Otitis Media.
Causes painless offensive discharge. May look like ear wax on the TM however this is particularly troubling if ear wax is not present in the outer 1/3 of the canal (i.e. hairy bit). Particularly common to see in Attic region due to retraction pockets being most common in the Pars Flaccida.
Must be surgically removed.
What are imp questions to ask in history of ear pathology?
Pain (Otalgia)- present? persistent? Discharge (ottorhoea)- colour? smell? chronology with pain? blood? Hearing loss- sudden or progressive? Systemic signs? Vertigo/ Dizziness? Balance issues? Facial change? Hx of ear trouble? Change of meds- ototoxic / recent Abx use. Tinnitus? Tonsilitis?
What is malignant OE?
Not ca but caused by Pseudomonas Aeroginosa. Aggressive form of OE that can be lethal.
More common in Diabetics, Immunocompromised, Elderly. It spreads from EAM to bone causing osteitis or osteomyeltis, severe pain and CN VII, IX, X, XI palsies (affected at jugular foramen) due to it spreading across skull base.
Granulation tissue in Ext audit meatus.
High dose IV Abx and possibly surgical debridement.
What is acute mastoiditis? What might alert you to this possibility?
Complication of AOM where pus spreads to the mastoid air cells causing bony erosion. The pus may spread through the bone subperiosteally or to the subcuticular region in postauricular space.
PC: AOM that has not settled, persistent otalgia, ottorhoea, hearing loss. Patient often systemically unwell, pus in EAM, poss perf TM. Sagging postero-superior canal wall, tender over the bone immediately sup to the ear canal (Macewen’s triangle), mastoid abscess- red oedamotous skin post to pinna and pinna pushed forward.
** Unilateral headache should alert intracranial complication**
How is a perforation managed?
- left alone to heal, if small may take just a few days
- monitoring
- myringoplasty (grafting with temporalis fascia)
Perforations are usually described based on whether tissue surrounds all of the perf (central) or no tissue surrounds a portion of the perf (marginal).
what do you expect to see on an audiogram? What changes would indicate conductive vs sensorineural hearing loss?
anything above the 20dB line is essentially normal (at any freq)
- in sensorineural hearing loss both air and bone conduction are impaired
- in conductive hearing loss only air conduction is impaired
- in mixed hearing loss both air and bone conduction are impaired, with air conduction often being ‘worse’ than bone
