Causes and types of hearing loss
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 which is 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
- 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.