Hearing Loss Types and Causes

To make informed decisions, it's helpful to understand your baby's specific hearing loss. Every child has a unique profile, but here are the basic facts.

Conductive Hearing Loss

• A conductive hearing loss involves the outer and/or middle ear. This includes the pinna (the part of  the ear you can see), the external auditory canal, the tympanic membrane (the ear drum), and/or the ossicles (the three tiny bones in the middle ear).
• Causes: There are many reasons a child may have a conductive hearing loss.
• Otitis Media- more commonly known as an ear infection. When they are chronic, the child is at risk for a hearing loss.
• Otitis Externa- an infection of the external auditory canal.
• Atresia- the child is born without an external auditory canal or a very small/narrow canal.
• Microtia/Anotia- the outer ear is very small or absent.
• Otosclerosis- the stiffening of the ossicles, often due to chronic otitis media.
• Ruptured or perforated tympanic membrane- a tear or hole in the ear drum. Can be caused by otitis media or trauma.
• In some cases, is required in addition to the use of listening devices. Click here to learn more about ear surgeries.
• This type of loss will NOT be helped by cochlear implants! However, there are other options available. Click the links to learn about hearing aids, hearing aid technology, and assistive listening devices.

Sensorineural Hearing Loss

• A sensorineural hearing loss involved the cochlea and/or auditory nerve.
• Causes: As with a conductive loss, there are many reasons a child may have a sensorineural loss.
• Prenatal
• Infections
• Rh factor complications- mom's blood creates anitbodies to baby's blood
• Fetal Alcohol Syndrome
• Anoxia- lack of sufficient oxygen
• Maternal diabetes
• Perinatal
• Anoxia
• Cochlea damage with forceps (this is quite rare)
• Postnatal
• Ototoxic drugs- some life-saving antibiotics can cause damage to the cochlea 
• High fever
• Influenza, meningitis, measles, mumps, rubella, encephalitis
• Genetics
• 50% of congenital hearing loss in children is thought to be due to genetics
• In 25% of cases, the causes are unknown
• 90% of children with severe to profound hearing loss have parents with normal hearing
• This type of loss can be helped by cochlear implants, hearing aids, and assistive listening devices.