External Auditory Exostosis

Aetiology / Pathology

• Chronic exposure to cold water and air stimulates periosteal bone growth in the canal

• Common in surfers, divers, swimmers, and others frequently in cold aquatic environments

• Typically presents as multiple, broad-based bony outgrowths near the tympanic ring

Symptoms / Presentation

• Recurrent ear infections or otitis externa (due to narrowed canal trapping debris and moisture)

• Sensation of ear blockage or discomfort

• Progressive conductive hearing loss in advanced cases (from canal narrowing or impacted cerumen)

• May notice frequent ear wax impaction due to restricted canal diameter

Examination

• Otoscopic inspection reveals bony mounds protruding into the EAC

• Canal may appear narrowed, limiting visualisation of the tympanic membrane

• Inflammation or debris can complicate the view if infection is present

Diagnosis

• Primarily clinical based on history (repeated cold water exposure) and otoscopic findings

• Audiometry if hearing impairment is suspected

• Imaging (e.g. CT temporal bones) may be considered for severe cases or surgical planning

Management

• Preventive Measures

  • Wear earplugs or neoprene hood when surfing or swimming in cold conditions

  • Thoroughly dry the ears after water exposure

  • Encourage avoidance of repeated exposure to cold wind or water if possible

• Medical Management

  • Treat infections or otitis externa promptly with topical agents to reduce inflammation and debris

  • Ear drops or gentle suctioning to manage impacted wax

• Surgical Removal

  • Indicated if canal stenosis is severe, recurrent infections, or significant hearing loss

  • Performed under microscope, removing exostoses with specialised drills

  • Risks include sensorineural hearing loss, facial nerve injury, and infection

  • Long-term follow-up may be required to monitor for regrowth

• Referral to ENT

  • Persistent or symptomatic cases

  • Progressive hearing loss, frequent infections, or difficulty in removing obstructive exostoses

  • Consideration of operative intervention if quality of life is affected

Notes:

• Early intervention and consistent preventive strategies can minimise complications

• Regular ear hygiene and protection help prevent recurrent exostosis formation and reduce infection risk

• Patients with significant bony overgrowth are at higher risk of cerumen impaction and external ear canal infections, emphasising the importance of ENT assessment if symptoms persist or worsen