3. Diseases of the pinna and the external ear canal

• Auricle (pinna)
  • Elastic cartilage
  • Collects sound waves
  • Diseases
    • Malformations
      • Protruding ears
      • Auricular appendages
      • Congenital auricular fistulas
        • Infections
      • Microtia
      • Anotia
      • Stenosis of ear canal
      • Creased lobule (CAD)
    • Inflammation (often bacterial/viral)
      • Often with otitis externa
      • Acute
        • Herpes zoster oticus
        • Cellulitis, dermatitis
        • Perichondritis
      • Chronic
        • Eczema
    • Trauma
      • Perichondral haematoma (cauliflower ear)
        • Accumulation of blood in perichondrium
      • Frostbite
      • Piercings

• External ear canal
  • Outer third is cartilage, inner 2/3 is bone
  • Thin keratinized stratified squamous epithelium
  • Contains ceruminous glands -> produce cerumen
  • Diseases
    • Swimming, Q-tip use, scratching
    • Acute
      • Diffuse otitis externa
      • Circumscribed otitis externa
      • Bullous otitis externa
    • Chronic
      • Necrotizing otitis externa (pseudomonas)
      • Eczema
      • Fungal infection (otomycosis)
      • Cholesteatoma
  • Symptoms
    • Otorrhoea
    • Pain
    • Conductive hearing loss