Impacted Cerumen

Accumulation of cerumen that causes symptoms, prevents adequate examination of the tympanic membrane, or obstructs audiological assessment or hearing aid function. Asymptomatic wax that permits a full view of the drum requires no intervention.

Physiology

Cerumen is a mixture of apocrine ceruminous gland secretion, sebum, desquamated keratin, lysozyme and immunoglobulin A. It maintains a canal pH of approximately 5.0 to 5.7, is hydrophobic, and is antibacterial and antifungal. Epithelial migration carries it laterally from the tympanic membrane at roughly the rate of nail growth, assisted by jaw movement. Impaction is a failure of this clearance mechanism.

Risk factors

• Cotton bud use, which compacts wax medially past the isthmus.
• Hearing aids, earphones and earplugs, present in up to 50 percent of hearing aid users.
• Narrow, tortuous or hairy canals, exostoses and osteomas.
• Advancing age, in which cerumen becomes drier and more keratotic and epithelial migration slows. Prevalence exceeds 30 percent in institutionalised elderly.
• Cognitive impairment, Down syndrome and inability to report symptoms.
• Dry cerumen phenotype associated with the ABCC11 gene variant common in East Asian populations.

Impacted wax is a genuine cause of morbidity in the elderly, contributing to hearing handicap, social withdrawal, hearing aid feedback and, in some patients, worsening of cognitive test performance that improves after removal.

• Hearing loss, which generally requires near total occlusion. Complete obstruction produces a conductive loss of 30 to 40 dB, and partial occlusion often produces none.
• Aural fullness and blockage.
• Itch and irritation.
• Tinnitus, usually low pitched.
• Vertigo or unsteadiness when the wax presses on the tympanic membrane or during removal.
• Reflex cough through stimulation of the auricular branch of the vagus.
• Otalgia when the mass is impacted against the drum.
• Hearing aid whistling, discomfort or reduced output.
• Sudden onset of symptoms after showering or swimming, as water causes the wax to swell.

Examination

Brown to black obstructing material with a smooth or laminated surface. Distinguish from keratin, which is white and flaky and raises the question of keratosis obturans or cholesteatoma.

Otoscopy establishes the diagnosis. The essential clinical discipline is to reassess after removal, since wax may coexist with the real pathology.

• Always visualise the tympanic membrane after removal. Failing to do so risks missing perforation, cholesteatoma, effusion or a canal tumour.
• Pure tone audiometry when hearing loss persists after clearance. Persistent loss requires explanation and is never attributable to the wax that has just been removed.
• Suspect keratosis obturans when the plug is white, densely packed, bilateral, and associated with severe pain and a widened canal, particularly in a younger patient with bronchiectasis or chronic rhinosinusitis.
• Suspect external auditory canal cholesteatoma when there is focal bone erosion, usually on the posteroinferior wall, with localised keratin and dull pain.

Cerumenolytics

Used alone in mild cases and for 3 to 5 days before removal in hard impactions. There is no consistent superiority of one agent over another.

• Sodium bicarbonate 5 percent drops, 3 to 5 drops twice daily for 3 to 5 days. Effective and inexpensive, but drying with prolonged use.
• Olive oil or almond oil, 3 to 5 drops once or twice daily. Softens rather than dissolves, gentle on the canal, suitable for long term prophylaxis.
• Docusate sodium and carbamide peroxide preparations, similar efficacy.
• Hydrogen peroxide 3 percent, which effervesces and fragments the plug, but is irritant and can worsen canal dermatitis.
• Do not instil any cerumenolytic when a perforation is known or suspected, in an open mastoid cavity, or in the presence of active otitis externa.

Irrigation

• Use an electronic irrigator with controlled pressure rather than a metal syringe.
• Water at body temperature, approximately 37 degrees Celsius. Cooler or warmer water produces caloric stimulation with vertigo, nausea and nystagmus.
• Direct the jet along the posterosuperior canal wall so that water passes behind the plug and floats it out.
• Dry the canal afterwards and inspect the drum.

Contraindications to irrigation

• Known or suspected tympanic membrane perforation, current or previous.
• Previous middle ear or mastoid surgery, including any mastoid cavity, and grommets in situ.
• Only hearing ear.
• Previous complication of irrigation, or vertigo during a prior procedure.
• Active otitis externa or a discharging ear.
• Diabetes and immunosuppression, given the risk of precipitating necrotising otitis externa.
• Uncooperative patient or young child.
• Cleft palate, whether repaired or not.

Manual removal under the microscope

The preferred method for all patients in whom irrigation is contraindicated, and the safest overall.

• Microsuction with a 3 to 5 French suction tip. Warn the patient about noise and possible transient vertigo.
• Jobson Horne probe, wax hooks and crocodile forceps for firm plugs, with the instrument passed beyond the plug and withdrawn.
• Never use forceps on a smooth spherical plug, which pushes it medially.
• Local anaesthesia is rarely needed. In an inflamed canal, defer removal, treat the inflammation, then clear.

Complications and their management

• Otitis externa in up to 15 percent after irrigation. Treat with microsuction and ciprofloxacin with dexamethasone drops.
• Tympanic membrane perforation, roughly 1 in 1000 irrigations. Keep the ear dry, avoid ototoxic drops, and review at 6 weeks with audiometry.
• Canal laceration and bleeding, usually self limiting.
• Vertigo, tinnitus and, rarely, sensorineural hearing loss.
• Necrotising otitis externa in the elderly diabetic, which is the strongest argument for microsuction over irrigation in this group.
• Retained water causing later infection.

Prevention

• Stop cotton buds and all self instrumentation.
• Olive oil 2 to 3 drops once weekly in patients with a tendency to accumulate wax.
• Scheduled 6 to 12 monthly review with microsuction for hearing aid users, patients with narrow canals or exostoses, and residents of care facilities.
• Advise hearing aid users to clean the mould daily and to have wax filters changed regularly.