12
Vol. 66, No. 1 2015
Northeast Florida Medicine
Otolaryngology
Cochlear implantation has allowed children to overcome
social and vocational isolation inherent to their hearing
loss. In 1984, the Food and Drug Administration (FDA)
approved the first cochlear implant for use in adults ages
18 and older. Five years later, the FDA approved the first
cochlear implant for use in children ages two years and older.
In 2000, the FDA approved the implantation of children as
young as 12 months of age.
In many cases, hearing loss is identified in children when
they are screened for hearing loss as newborns. Although
children with hearing loss are identified at a much younger
age with newborn screening, we continue to see implant
candidates who have had progressive hearing loss. For
example, childrenwith hearing loss due to enlarged vestibular
aqueduct syndrome and those withmutation of the connexin
26 genemay pass newborn screening and still have progressive
loss. In a recent study, up to 30 percent of pediatric cochlear
implant recipients were not identified as hearing impaired as
newborns.
1
This will affect the age at implantation as children
identified with newborn screening with hearing loss were
implanted at 1.7 years, and those who passed or were not
screened were implanted at 2.6 years.
1
Once identified, a
child then undergoes definitive audiometric testing, which
is most likely a sedated auditory brainstem response and
otoacoustic emissions. This includes testing for auditory
neuropathy/dyssyncrony. Children identified later may be
evaluated by age appropriate behavioral audiometry. If the
child is found to have a profound hearing loss, the cochlear
implant process begins.
Evaluation of a child for a cochlear implant is a multi-
faceted process. After review of previous medical records,
childrenwill be evaluated by several members of the cochlear
implant team. The team consists of an implant surgeon,
cochlear implant audiologist, speech pathologist, genetics
and ophthalmologist.
Themedical and surgical evaluationbegins with a thorough
medical history and a physical performed by a physician. It
includes a focus on prenatal, perinatal and postnatal causes
of the child’s hearing loss. Family history of a hearing loss
is also important. Then, the diagnostic work-up proceeds.
The use of routine laboratory testing is not needed in most
children with hearing loss. Laboratory testing should be
performed on a case by case basis, depending on the possible
cause of the hearing loss.The use of routine laboratory testing
has a low yield in establishing the diagnosis of hearing loss
ranging from zero to two percent.
2,3
Children with newly diagnosed hearing loss will require
imaging. There is controversy, however, regarding the
appropriate imaging study to obtain.The long time standard
has been a computerized tomography scan (CT) of the
temporal bones. Magnetic resonance imaging (MRI) in the
past was considered expensive and required sedation. MRI
for hearing loss, however, is faster and provides excellent
anatomic information of the temporal bone.
4
In addition,
there is some suggestion that since some studies have found
no association betweenGJB2-positive children and temporal
bone abnormalities, these children do not need imaging if
they have a hearing loss not requiring cochlear implantation.
5,6
An integral part of the evaluation process is the speech
and language evaluation. Often times, young children
are incapable of speech or language and cannot complete
traditional speech perception testing. The speech language
pathologist on the cochlear implant team will complete
appropriate testing and observation of a child to assess
benefit from hearing aids. An aural rehabilitation/speech-
language evaluation for a cochlear implant can be difficult
to define. The process varies depending on the age of the
child, the current mode of communication and overall
language ability. Young infants and toddlers are not typically
given formal assessments; the evaluation primarily includes
parent questionnaires, play-based interactions and clinician
Address correspondence to:
Drew M. Horlbeck, MD
Nemours Children’s Clinic
Division of Pediatric Otolaryngology
807 Children’s Way,
Jacksonville, FL 32224
Pediatric Cochlear Implants
By Drew M. Horlbeck, MD
Abstract:
Pediatric cochlear implantation has allowed children to
overcome social and vocational isolation inherent to their hearing loss.
Evaluation of a child for a cochlear implant is a multi-faceted process.
The medical and surgical evaluation begins with a thorough medical
history and a physical performed by a physician. It includes a focus
on prenatal, perinatal and postnatal causes of the child’s hearing loss.
An integral part of the evaluation process is the speech and language
evaluation. This multidisciplinary approach to the cochlear implant
evaluation process allows for a comprehensive picture of the child’s
hearing, listening skills, hearing aid benefit and medical issues.
