Causes of Hearing Loss

Hearing loss can be categorized by which part of the auditory system is affected. There are 3 basic types of hearing loss: sensorineural, conductive and mixed

Sensorineural Hearing Loss

– Occurs when there is damage to the inner ear (cochlea) or hearing nerve in the brain.
– Some causes of sensorineural hearing loss include:

• Aging – gradual age-related hearing loss is called presbycusis
• Excessive exposure to loud noise
• Viral or bacterial infections
• Certain Medications
• Meniere’s Disease
• Acoustic Neuroma –  a tumour located between the ear and the brain
• Hereditary factors

Conductive Hearing Loss

– Occurs when sound is not conducted efficiently through the ear canal, ear drum or middle ear.
– Some causes of conductive hearing loss include:

• Infection of the ear canal or middle ear
• Fluid in the middle ear
• Perforation or scarring of the eardrum
• Wax build-up
• Dislocation of the ossicles (three middle-ear bones)
• Foreign objects in the ear canal
• Otosclerosis
• Unusual growths, tumours

Mixed Hearing Loss

– Occurs when there is a combination of both sensorineural and conductive issues. In other words, both the middle ear and inner ear are affected.