Introduction

It is estimated that some degree of hearing loss exists in 1/100 of live births, in which 1/1000 ( 0.1 % ) has severe hearing loss. 5% of children under 18 years old suffer from history of hearing loss. Hearing loss can be present at birth or progress over time. Hearing loss can be hereditary or acquired by environmental means.

Characteristics

Because most children with hearing loss have no other abnormalities or distinguishing features ( called non-syndromic hearing loss ), it is difficult to diagnose the hearing problem in children earlier. Many children are not noted to have hearing loss until some significant sequel such as delay in language development establishes.

Etiology

Genetic factors contribute to development of hearing loss in 50 % of prelingual deaf children ( the “ prelingual ” means that “hearing loss obtains prior to the acquisition of speech”). Non-genetic factors such as environment factors contribute to another 25 % of prelingual deafness. The common environmental factors include some typical infection diseases such as meningitis and otitis media. 25 % of prelingual deafness is idiopathic.

Diagnosis

Because of the poor compliance, accurate hearing testing is often difficult and time consuming in children. Some screening tests such as otoacoustic emission ( OAE ) could be performed in newborns or infants. In toddlers, behavioral observation audiometry is a common hearing test used by experienced audiologist. Objective hearing tests include auditory brainstem responses ( ABR ) or steady state evoked potentials ( SSEP ). The diagnosis of pediatric hearing loss requires careful investigation of family history and physical examination. Advances in genetic testing ( molecular biology ) have extended our ability to investigate the causes of hearing loss.

Treatment

The management of a deaf child is a team approach, including the family, otolaryngologist, pediatrician, audiologist, school teacher, and a speech and language pathologist. All the associated medical problems should be actively and aggressively treated. Early diagnosis and treatment cannot be overstressed.

Prevention

Early intervention and treatment of hearing loss via the appropriate form of rehabilitation is essential to developing appropriate cognitive development as well as speech and language development.