Hearing loss is invisible and nearly always painless. It can also develop slowly over time. The number one cause of hearing loss is exposure to excessive noise. The normal aging process is a close second – and it starts much earlier than you might think. Changes in hearing begin at age 20, with significant decline in hearing ability occuring as early as 40 years of age.
There are two types of hearing loss: sensorineural and conductive. Here's a quick overview of both:
Sensorineural is the most common type of hearing loss and is caused by withering of the hair cells in the inner ear due to age, noise damage, or medications. Without these tiny hair cells, the ear cannot detect sounds properly. The vast majority of people with this kind of hearing loss benefit greatly from amplification with hearing aids.
Conductive hearing loss is the result of structural damage to the ear. This kind of loss can be caused by:
- Impacted wax
- Perforated eardrum
- Middle ear effusion (escape of fluid into the middle ear behind the eardrum)
- Otosclerosis (bones of the middle ear become immobile)
- Cholesteatoma (accumulation of tissue in the middle ear)
- Congenital anomalies
Other common causes for hearing loss include:
- Ototoxic drugs (certain antibiotics)
- Viral and toxic illness
- Disturbances of fluid in the inner ear