Hearing loss in children

Hearing loss can cause detrimental effects on speech, language, development, educational, and cognitive outcomes in children.

It is recommended that newborn hearing screening test be done within the first three months of life.

Advances in hearing screening and cochlear implantation allows more than 75% of children with hearing loss to attend public schools mainstreamed with normal hearing students.

17-48% of children with unilateral hearing loss and 50% with cochlear implant have impaired vestibular function which influences their ability to participate in normal childhood activities.

Long-term studies have found significant relationships between childhood hearing loss and decreased well-being and self-esteem, along with anxiety and depression among women.

Prevalence of permanent bilateral severe-profound hearing loss in newborns is 1.1 per 1000 newborns.

There is an association with conduct and hyperactivity disorders and other emotional problems.

The most common causes of permanent congenital sensorineural and mixed hearing loss are congenital cytomegalovirus, 5-20%, structural abnormalities of the temporal bone, 30-40%, and genetic causes 50%.

Many  anatomical abnormalities are associated with genetic causes: branchiootorenal syndrome and CHARGE syndrome.

The incidence of hearing loss increases with premature birth and decreases with increasing gestational age and birthweight.

Hearing loss is present in 1.2-7.5% of infants in neonatal ICU ‘s.

Neonatal hearing loss increases with hyperbilirubinemia, sepsis, neonatal bacterial meningitis, necrotizing  enterocolitis, prolonged ventilation, ototoxic medications, and extracorporeal memory oxygenation.

Congenital CMV is usually a primary cause of hearing loss but other genetic or structural temporal bone abnormalities may also present with hearing loss.

Congenital infections such as syphilis and rubella can cause hearing loss.

Delayed onset hearing loss can occur with perinatal risk factors such as congenital CMV infection or extracorporeal membrane oxygenation.

Delayed onset hearing loss maybe associated with Pendred,Usher, and Alport syndromes.

119 genes affecting sensorineural or mixed hearing loss of been described.

Thirty percent of all genetic causes of hearing loss are associated with delayed onset or progressive hearing loss.

Postnatal acquired causes of hearing loss in children can be attributed to trauma, infection, ototoxic medications, or autoimmune disorders.

Much of pediatric hearing loss is due to acquired etiologies.

Preventable causes of childhood hearing loss include infections, 31%, postnasal birth complications, 17%, the use of ototoxic medications such as aminoglycosides by pregnant mothers and infants 4%, and 8% of the causes.

Trauma can cause conductive, mixed, or sensorineural hearing loss depending on the type of temporal bone injury.

Conductive hearing loss can result from tympanic membrane perforation or ossicular chain injury.

Temporal bone fractures can damage the cochlea, the cochlear nerve and result in sensorineural hearing loss.

Concussive injuries to the temporal bone without fracture may result in temporary or permanent sensorineural hearing loss.

Trauma to the cochlear can be in the form of noise exposure damaging the hair cells resulting in permanent loss.

Infectious causes of sensorineural hearing loss include: measles, mumps, varicella zoster, Lyme disease, bacterial meningitis, and, rarely, otitis media.

Ototoxic medications can cause permanent hearing loss and include: aminoglycosides, anti-neoplastic drugs, such as cis-platinum, and loop diuretics.

Salicylates and macrolides can cause hearing loss that is generally reversible.

Auto immune related hearing loss can be a cause of inner ear dysfunction.

Bilateral input to the auditory system, as opposed to unilateral input, improves biaural listening skills necessary to develop spoken language skills, effective communication, and learning, and ultimately academic success.

For children with bilateral sensorineural hearing loss , each of the ears should be fitted  with a hearing device.

Device options for children with bilateral sensorineural hearing loss consist of: 2 hearing aids, two ((cochlear implants)), or a cochlear implant in one year and a hearing aid in the opposite ear.

In children with mild to severe hearing loss use of hearing aids is associated with lower spoken language outcomes than their typically hearing peers: scores for receptive language, expressive language, speech production, and vocabulary range from 0.5-2 standard deviations lower than their  normative mean for typically hearing peers.

Initially cochlear implants were recommended for children with profound sensorineural hearing loss demonstrated no benefit from conventional hearing aids, now guidelines are expensive expanded to consider cochlear implants for children with less severe hearing loss.

Criteria for placing a cochlear implant in children with bilateral profound sensorineural hearing is from nine through 24 months and older than two years for children with severe to profound sensorineural hearing loss.

The early receipt of a cochlear implant is safe is and associated with a greater likelihood of improve spoken language and academic outcomes.

Children with cochlear implant implants with a history of bilateral severe to profound hearing loss can attain age-appropriate speech Perception, speech production, and expressive and receptive language skills by the time they at the elementary school, although 30-50% fail  to achieve age-appropriate spoken language skills.

Unilateral hearing loss leads to harmful effects on speech and language development, educational difficulties and behavioral issues.

Unilateral hearing loss options include: hearing aids, frequency modulating systems, contralateral routing of signal aids, bone conduction hearing aids, and cochlear implant.

Frequency modulating systems transmit sound from the person wearing the transmitter to the hearing aids being worn, reducing distracting background, listening fatigue, and the distance between the speaker and listener.

Contralateral routing of signal hearing aids collect sand from the year with the hearing loss and routes it to the better hearing ear.

Bone conduction hearing aids bypass the middle ear, directly stimulating the auditory nerve on the same side if is functioning or to the opposite ear with normal hearing.

Cochlearimplant‘s directly stimulate the auditory nerve through an electrode placed into the cochlea.

In children with severe to profound unilateral sensorineural hearing loss, bone conduction hearing devices show improvement in hearing thresholds, speech recognition and hearing in noisy environments.

Cochlear implants have been approved for profound hearing loss for children older than five years.