6. Diseases of the auricle and external auditory canal.

What are developmental abnormalities

• protruding ears

• auricular fistulas and cysts

• auricular appendages

• auricular dysplasia

• stenosis and atresia of the external ear canal

What is the treatment of developmental abnormalities

• surgerry

• BAHA hearing aid if outer ear canal atresia

What are the types of injury of the external ear

• thermal injjry

• trauma

• auricular avulsion

• foreign bodies

Describe thermal injury

• frostbite, burns

• damage confined to skin

  • Grade 1- local erythema

  • Grade 2- blistering of the skin

• Damage involving the skin- cartilage unit

  • Grade 3- deep tissue necrosis

Describe external ear trauma

• auricular hematoma/ seroma- collection of serous fluid between the perichondrium an auricular cartilage

Describe auricular avulsion

• open injury where cartilage is exposed over an area of variable size

• can be

  • partial- with intact bridge of skin

  • complete- part of the auricle is completely detached

what is the treatment of injury

• disinfection with 3% H2O2

• antibiotics

• tetanus injection

• cover wound with sterile dressings

What is the treatment of ear canal injuries

• with no signs of tympanic membrane or ossicular chain injury

• sterile Burrow strip with antibiotics can be inserted into the canal

What is the treatment of foreign bodies

Removal with extraction hook

What is the treatment of hematoma/ seratoma

• Paracentesis if small

• drainage if big + surgical evacuation and reattachment of perichondrium to cartialage

What is the treatment of auricular avulsion

• remove naked cartilage pieces and sew freee edges together ± skin transplant

• torn helix part of whole helix can be transported on ice in sterile sheet with saline to keep alive until surgery

  • performed within 1-2h

What is the treatment of frostbite and burning

• keep surface sterile ± anticoagulant therapy

• frostbitten areas gently warmed and circulatory stimulats

  • dextrans or pentoxifylline

• surgery can only be performed after 6 months when site has completely healed

• superficial burns should be cooled immediately and treated with local anti inflammatory drugs

What are the tumouts of the external ear

• Precancerous lesions:

  • Actinic keratosis, Bowen’s disease, cutaneous horn

• Benign tumors:

  • Papillomas, angiomas, fibromas, adenomas, osteomas, atheroma, chondrodermatitis

• Malignant tumors:

  • Basal cell carcinoma, squamous cell carcinoma, malignant melanoma

What are non inflammatory diseases of the external ear

• Cerumen impaction

• Exostoses

What is cerumen impaction

• Cerumen= earwax

• mixture of secretion from ceruminous and pilosebaceous glands, squamous epithelium, dust, debris

What is the etiology of cerumen impaction

• Disturbance of normal self cleaning mechanism

• excesive cerumen secretion

What is the risk factors of cerumen impaction

• hairy or narrow ear canals

• in ear hearing aids

• cotton swab use

• osteomata

What is clinical signs of cerumen impaction

• CHL → cerumen impaction is the most common cause of CHL for those aged 15-50

• other symptoms- tinnitus, vertigo, otalgia, aural fullness

How do you diagnose cerumen impaction

• inspection

• otoscopy

How do you treat cerumen impaction

• cerumenolytic ear drops

• removal with a hook (Jansen hook)/ curette or by aural irrigation

What is exostoses

• bony protuberances in external auditory canal composed of lamellar bone

• most commonly located near the annulus on superomedial canal wall

What is the etiology of exostoses

• associated with swimming in cold water

What are the clinical signs of exostoses

• usually an incidental finding

• if large, can cause cerumen impaction or otitis externa

How do you treat exostoses

• no treatment required unless symptomatic

What are the inflammatory diseases of the auricle

• eczema and dermatitis

• perichondritis

• cellulitis

• herpes zoster oticus

define perichondritis

inflammation of skin, perichondrium and auricular cartilage

define cellulitis

acute streptococcal infection of the subcutaneous tissue of the auricle

how do you treat inflammatory diseases of the auricle

• mild- topical and oral antibiotics

  • amoxicillin, cephalosporin, macrolides

• severe- IV antibiotics

What is Herpes zoster oticus

• Ramay Hunt syndrome

What is the etiology of Herpes zoster oticus

• reactivation of dormant VZV in ggl cells

• HZO CN VII and/or VIII

What are the clinical signs of Herpes zoster oticus

• initially, ear pain, burning on one side in the absence of physical findings

• then vesicles erupt a few days later →

  • severe pain of pinna, mouth or face

  • SNHL

  • vestibular symptoms- vertigo, nystagmus, disequilibrium

  • facial nerve palsy

  • lymphadenitis of cervical LN

How do you diagnose Herpes zoster oticus

• history + insepction

• examination of facial nerve

• lab- direct electron microscopy and serology

What is the treatment of Herpes zoster oticus

• systemic antivirals → acyclovir, valaciclovir, famciclovir

• high dose B12 + NSAIDs

• facial nerve palsy → CS

What are the inflammatory diseases of the external auditory canal

• acute diffuse inflammation

• circumsribed ear canal inflammation- furunculosis

• chronic ear canal inflammation

  • eczema, atopic dermatitis, psoriasis

• otitis externa

• necrotising malignant otitis externa

  • skull base osteomyelitis

What is the etiology of otitis externa

• Bacteria 90%

  • pseudomonas- aeruginosa, vulgaris

  • E coli, S aureus

What are the risk factors of otitis externa

• swimmers ears

• mechnical cleaning Q tip, skin dermatitis, aggressive scratching

• devices that occlude the ear canal- hearing aids, headphones etc

• allergic contact dermatitis, dermatological conditions

  • psoriasis, atopic dermatitis

• absence of cerumen, cerumen impaction

What are the symptoms of otitis externa

• earache, external part of ear canal is painful

  • especially tragus

• discharge, itching

• ear congestion, hearing loss

• fever is uncommon

What are the clinical signs of otitis externa

• swelling and hyperremia of the skin of the ear canal

• serous or purulent discharge

• accumulation of debris in the ear canal

• tympanic membrane appears to be normal

How do you diagnose otitis externa

• inspection + palpation

• otoscopy

• lab- culture and sensitivity testing

How do you treat otitis externa

• discharge removal, thorough cleaning

• burrow gauze strip placed in ear canal

• disinfection- betadine, boric acid dust

• antibiotic, antimycotic and steroid combination cream on gauze

• ear drops

  • antibiotic, antimycotic, steroid drops

What is necrotising malignant otitis externa

• osteomyelitis of the temporal bone

What is the etiology of necrotising malignant otitis externa

• rare complicatoin of otitis externa

• pseudomonas infection in 99% of cases → occurs in elderly diabetics and immunocompromised patients

what are the clinical signs of necrotising malignant otitis externa

• otalgia and purulent otorrhea- refractory to medical therapy

• granulation tissue on the floor of auditory canal

• complications → cranial nerve palsy, systemic infection= death

How do you diagnose necrotising malignant otitis externa

• inspection + palpation

• otoscopy

• lab- culture and sensitivity testing

• imaging- high resolution CT, gadolinium enhanced MRI, technetium scan

how do you treat necrotising malignant otitis externa

• requires hospital admission, debridement, IV antibiotics, hyperbaric O2

• may require surgery for debridement of necrotic tissue/ bone