ENT JC097: Common Ear Diseases And Hearing Loss Flashcards
Type of deafness
- Conductive
- Eardrum
- Ossicles - Sensori-neural (difficult to distinguish between sensory / neural)
- Cochlea
- Auditory nerve
- Brainstem - Mixed type
- e.g. Chronic suppurative otitis media
Assess Hearing loss
***Pure tone audiogram PTA
- Thresholds (softest sound when patient notice)
—> 2 types:
—> Air conduction (sound heard from external ear)
—> Bone conduction (vibrator on mastoid process)
Severity of hearing loss —> assess through **Decibel + **Frequency:
1. Decibel
- <20: normal
- 20-40: mild
- 40-70: moderate
- 70-90: severe
- >=90: profound
***Causes of Conductive deafness
- External ear canal
- Congenital meatal stenosis (no external ear canal at all) - Middle ear problem
- Eardrum perforation
- Ossicular chain problem (not in continuity), infection, post-op, Otosclerosis (spongy bone replace part of normally dense enchondral layer of bony otic capsule (footplate of stapes)), tumour
- Middle ear fluid
***Causes of Sensorineural deafness
Children:
1. Born profoundly deaf, genetic
2. Neonatal (e.g. uncontrolled neonatal jaundice)
Adult:
1. **Meningitis
2. Ear / Head trauma
3. Noise
4. Inner ear dysplasia, Deficient inner ear (hearing loss even from a minor trauma)
5. **Drug-induced e.g. TB drugs (Gentamicin)
6. Chronic ear infection
7. ***Cochlear otosclerosis
8. Radiotherapy
Consequences of Deafness
In-born:
1. Deaf + dumb (affect development of language and speech)
2. Education
Adult:
1. Communication / social
2. Occupation
3. Socio-economic
4. Safety issue in daily activities
***Common ear diseases
External ear:
1. Pinna
- Preauricular sinus
- Accessory auricle
- Bat ear
- Microtia +/- Meatal atresia
- Pinna keloid
- Perichondritis
- Herpes zoster
- Haematoma auris
- Pinna carcinoma
- External ear canal
- Impacted wax
- Foreign body
- ***Otitis externa
- Osteoradionecrosis
- Aural polyp
- Squamous carcinoma
- Malignant tumour (not from ear canal)
NB: External ear diseases **seldom is cause of hearing problem (Need to look for **Middle ear problems)
Middle ear:
1. Tympanosclerosis
2. **Acute otitis media (AOM) (急性中耳炎)
3. **Chronic suppurative otitis media (CSOM)
4. Traumatic perforation
5. Otitis media with effusion
6. Haemotympanum
7. Congenital cholesteatoma (unrelated to “Unsafe” CSOM)
8. Glomus tumour
9. Facial nerve neuroma
Inner ear:
1. Temporal bone fracture + Ear injury
2. ***Acoustic neuroma (Vestibular schwannoma)
- Pinna diseases
- Preauricular sinus
- developmental defects of the first and second pharyngeal arches
- most asymptomatic, but can be infected - Accessory auricle
- developmental defects
- no effect on hearing - Bat ear (兜風耳)
- Microtia +/- Meatal atresia
- malformation of pinna
- usually have middle ear deformity as well
- more severe the external ear deformity —> more severe the middle ear structure - Pinna keloid
- ∵ trauma (e.g. ear piercing) - Perichondritis
- inflammation of cartilage of pinna - Herpes zoster
- Ramsay-Hunt syndrome: **Sensory hearing loss (poor recovery potential), **CN7 (facial paralysis, poor recovery potential), Vesicles on pinna skin (can go away) - Haematoma auris
- blood under perichondrium ∵ trauma
- need to be dealt with early —> ∵ pinna cartilage depend on blood supply from perichondrium —> necrosis of cartilage if left untreated —> permanent deformity (cauliflower ear, although not affect hearing) - Pinna carcinoma
- ∵ pinna often exposed to sunlight
- External ear canal diseases
- Impacted wax
- wax are normal + antiseptic —> normally pushed out spontaneously
- can be infected - Foreign body
- esp. in paediatrics
- ***mercury battery most dangerous —> local pressure + electricity + chemical damage
- cotton wool bud, plastic, insect - ***Otitis externa
- Diffuse (more common): Skin infection of external ear canal (EAC)
- Furunculosis: Localised, hair follicles, cartilaginous part of EAC, abscess - Osteoradionecrosis
- exposed bone in EAC (∵ necrosis of soft tissue + bone in EAC due to ***RT) —> prone to infection - Aural polyp
- soft tissue with discharge (result of infection / inflammation —> granulation)
- may have underlying ***neoplastic process (may need biopsy if not respond to general treatment) - Squamous carcinoma
- rare but lethal - Malignant tumour (not from ear canal)
- e.g. spread from parotid gland posteriorly
Otitis externa
S/S:
- Pain
- Discharge
- ***NO hearing loss
Causative organism:
- ***Staphylococcus aureus
Predisposing / Triggering factors:
1. Narrow ear canal (congenital, trauma)
2. Skin disease (e.g. eczema)
3. DM
4. Humidity (“Singapore ear”)
5. Impacted ear wax
6. Foreign bodies
7. Swimming, Shower (Swimmer’s ear)
8. Scratching, pricking —> Abrasion (breakage of epidermis —> introduction of bacteria)
Treatment of Diffuse otitis externa:
1. Local cleansing
- remove wax / foreign body
- suction clearance
2. Keep away from moisture (no swimming for 2-3 weeks)
3. ***Local antibiotic eardrops (against Staphylococcus aureus)
4. Correct underlying causes
- Small meatus
- Osteoma
Fungal otitis externa:
- Aspergillosis
- Candidiasis
- usually in ***overuse of antibiotic eardrops (usually should be <1 week)
- Treatment: Cleansing + Anti-fungal
Middle ear diseases
- Tympanosclerosis
- scarring in middle layer of eardrum (∵ infection, middle ear effusion during childhood)
- usually ***no hearing problem - ***Acute otitis media (AOM) (急性中耳炎)
- ***Chronic suppurative otitis media (CSOM)
- Traumatic perforation
- usually good healing power, usually heals within ***3-4 weeks
- no treatment needed (not even cleaning up blood)
- document baseline hearing loss —> see any improvement later - Otitis media with effusion
- Haemotympanum
- **skull base fracture: ear trauma, head trauma
- **conductive hearing loss
- usually blood absorbed within 2-3 weeks time - Congenital cholesteatoma (unrelated to “Unsafe” CSOM)
- intact ear drum
- **conductive hearing loss
- occasionally **CN7 palsy ∵ inflammation - Glomus tumour
- vascular tumour - Facial nerve neuroma
- ***Acute otitis media (AOM) (急性中耳炎)
- Inflammation of middle ear cleft
- Ascending infection (coming from nasopharynx)
- ***Children (∵ Eustachian tube more horizontal + relatively large compared to middle ear cavity)
Causative organisms:
1. **Viral (initially)
2. **Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis
S/S (紅腫痛熱):
- Pain
- Deafness, **Conductive (∵ effusion)
- Constitutional symptoms (sick, tired, fever)
- **NO otorrhoea (unless eardrum perforated)
Initial stage:
- middle ear still filled with ***air / thin fluid
- congested vessels on eardrum
Late stage:
- middle ear filled with ***pus
- congested vessels on eardrum
Treatment:
1. Oral antibiotics (against Gram +ve bacteria)
- ***Amoxicillin
- Erythromycin
- Co-trimoxazole
- Cefuroxime (2nd gen)
—> 7-10 days
—> generally good response
- Supportive treatment for fever / pain
- ***Myringotomy (Drainage of pus + culture) if resistant
- under GA
- release pressure to relieve symptoms
- culture to find out antibiotic sensitivity
- ***Chronic suppurative otitis media (CSOM)
Persistent, non-healing eardrum ***perforation
S/S:
- Recurrent otorrhoea / infection
- Hearing loss (usually **conductive, sometimes mixed)
- Inactive state: **No pus, only perforation with hearing loss, no infection / discharge
- Active state: ***Discharge + perforation + hearing loss
Original causes of perforation in CSOM:
1. Severe AOM
2. Trauma
- Direct mechanical
- Iatrogenic e.g. grommet
- Barotrauma
- Blast injury
Types of CSOM:
1. Central perforation (more common)
- aka **Tubotympanic disease / “Safe” CSOM
- perforation on **Pars tensa (central)
- Marginal perforation / Attic perforation / Cholesteatoma (presence of keratinising squamous epithelium in middle ear)
- aka **Atticoantral disease / “Unsafe” CSOM —> **higher chance of complications
- perforation on ***Pars flaccida (rim)
Causative organisms:
1. ***Mixed
- Staphylococcus aureus
- Pseudomonas aeruginosa
- E. coli
- Bacteroides fragilis (anaerobes)
- Fungi (∵ overuse of antibiotic eardrops)
- Aspergillosis
- Candidiasis - TB
- rare (e.g. resistant to usual treatment)
Clinical approach to CSOM:
1. Otoscopic diagnosis
- Persistent perforation
- Type of CSOM (Tubotympanic disease vs Atticoantral disease)
- Active infection?
- Ear swab + Bacterial culture - ***Audiological assessment
- Pure tone audiogram (degree of conductive hearing loss + assess whether inner ear damaged (sensorineural hearing loss as well)) - Local cleansing, Ear mopping
- ***Broad spectrum antibiotic eardrops
- systemic oral antibiotics usually not required
Definitive management of “Safe” CSOM
- Hearing improvement
- Tympanoplasty (eardrum repair)
- Hearing aid - Prevent otorrhoea
- Tympanoplasty - Activity, water sports
- Tympanoplasty
“Unsafe” CSOM
Cholesteatoma:
- Erosive and expanding growth
- Consisting of keratinizing squamous epithelium in the middle ear and/or mastoid process
Complications:
1. Extracranial
- **CN7 paralysis
- **Ossicular chain erosion —> conductive hearing loss
- ***Labyrinthitis (Inner ear inflammation)
- Lateral SCC (semi-circular canal) fistula
- SC / Subperiosteal abscess
- Intracranial
- **Extradural abscess
- **Subdural abscess
- Sigmoid sinus thrombophlebitis
- Meningitis
- Brain abscess (temporal lobe, cerebellum)
- Otitic hydrocephalus
Management:
1. Otoscopic diagnosis
2. Complications (e.g. CN7 palsy, inner ear damage)
3. Audiological assessment (e.g. how much hearing damaged)
4. **Definitive surgery
- must have surgery
- **Mastoidectomy
—> eradicate Infection + Cholesteatoma from middle ear —> prevent complications
- Otitis media with effusion
- air-fluid level in middle ear
- usually ∵ obstruction in Eustachian tube
- common in children (∵ inflammation)
- in adults —> suspicious (i.e. obstruction by malignant conditions)
Causes:
1. Mechanical obstruction
- **Enlarged adenoid
- **Tumour e.g. NPC
- Poor mucociliary clearance in Eustachian tube
- Infection
- Rhinitis
- Post-irradiation - Eustachian tube dysfunction
- Cleft palate
- Post-op
