Types of hearing loss
The most common causes of hearing loss are age or overexposure to loud noise. But hearing loss can also be caused by infection, a head injury, cancer treatments, or taking certain medications.
Hearing loss can be caused by problems in the outer and middle ear or by damaged cells or fibres in the inner ear. Or it can be a combination of both.
Outer and middle ear hearing loss (Conductive)
Conductive hearing loss is caused by problems in the outer and middle ear, which can prevent sounds getting through to the inner ear. The most common causes are a build-up of wax in the ear canal, perforated eardrums, fluid in the middle ear, or damaged or defective middle ear bones (ossicles).
Inner ear hearing loss (Sensorineural)
This type of hearing loss happens when the delicate nerve fibres in the inner ear get damaged, which prevents them from transmitting sound properly. It can be caused by excessive exposure to noise, but the most common causes of sensorineural hearing loss are the natural processes of ageing. For some the sensory cells wear out already at the age of 50 whereas others have only negligible hearing loss even at the age of 80. This condition is permanent in most cases.