Sensorineural Hearing Loss / Inner Ear Hearing Loss
Sensorineural Hearing Loss (SNHL) happens when the inner ear hearing mechanism isn't working. This is quite different to conductive hearing loss, which happens when the outer ear, ear drum or middle ear are affected.
What causes inner ear hearing loss?
Inner ear hearing loss affects 0.3% of all schoolchildren. Often it is present at birth or develops shortly afterwards, but it can develop at any age. There are some things that make it more likely that a child will have hearing loss, including having other family members with deafness, some medications, infections such as mumps or meningitis or rubella, low birth weight, prematurity, other genetic health problems, or if the parents were related before marriage. In about a fifth of children a specific cause cannot be identified.
It's important to get vaccinated as recommended by your GP, as several of the infections that can cause hearing loss are preventable by vaccination.
How is sensorineural hearing loss identified and investigated?
Many babies will be identified at the new-born hearing screening, and in others the parents will notice a problem within the first few months of life. Children with a lesser degree of hearing loss may only be identified later on, perhaps with speech difficulties or behavioural problems or problems at school.
If the hearing loss is one sided rather than on both sides, parents may notice no problems at all in the first few years of life! This is because if one ear is working, children manage nearly as well as they would with both ears. In children with one sided loss, they develop normally and speech is OK. The hearing loss may be picked up completely coincidentally on a routine test at some stage, or because the child becomes old enough to notice that the two ears are different.
Dedicated hearing tests will be required to determine the degree of hearing loss and its nature. Depending on that, children may need other investigations to try and find a cause, for example blood tests or scans or heart tracings. Don't be surprised if the doctors are interested in parents' and relatives' health and hearing, so it is worth making notes about any other health problems that the child's relatives may have.
How is inner ear hearing loss treated?
Hearing loss can have personal, educational and social implications for a child and their family. Once identified, health professionals aim to offer a holistic approach to help you navigate any problems encountered. Early identification helps children with hearing loss develop better language, speech, social and emotional development.
Health professionals can offer a number of ways to support children and family members with advice and information. If the hearing loss is severe, a team of professionals including audiologists (people that do hearing tests and manage hearing aids), teachers, and surgeons will be available to help and guide you. If hearing is more mild or one sided, little treatment may be needed. But if more severe, then hearing aids, surgery, or school help may be required. Have a look also at hearing aids and cochlear implants.
Section contributor:
Mitra Mummadi MRCS
ENT registrar