Child deafness detection

What is deafness?

In medical terms deafness is called hearing loss, which means, total or partial lack of hearing. It is one of the most serious problems that can affect a child. Parents should observe the baby's behavior during its first months of life to sound stimuli. During the first two months of life the newborn blinks, wakes up or is frightened by loud and high intensity noises; His mother's voice is able to reassure him and he pays attention to listening to her. At 3 and 5 months of life he directs his gaze and turns his head towards the sound source and between 6 and 9 months he is able to search for the source of the voice or sound by moving his head and body to observe it. Parents should immediately consult a Pediatrician if they think their child is not hearing well. The most serious consequence of childhood deafness, if not detected early, is the absence of language. A deaf child may have apparently normal development up to 18 or 24 months of age, in which a delay in language acquisition may be normal, so that the child is deaf may be overlooked. The problem with late detection is that these children do not speak because they do not hear, so detection and treatment must be as early as possible for the child to develop language. The warning signs in language development that should make us suspect the presence of hearing loss are:

• 6 months: does not make sounds or babbles
• 12 months: does not hear sounds (doorbell, telephone), does not recognize their name
• 15 months: does not imitate simple words
• 24 months: does not speak words (10)
• 36 months: two-word phrases
• 48 months: simple sentences

Deafness does not affect only the child, but all the people around him: family, friends and teachers. It is for this reason that its early detection should be a priority.

Causes of deafness in the newborn

About 1 to 3 out of every 1,000 newborns are deaf. Broadly speaking, half of the cases of deafness in the newborn are of hereditary or genetic cause (generally they are the most serious cases). For this reason, it is important to inform the Pediatrician if there is any case of deafness in the family. Some inherited forms of deafness are associated with other malformations or physical problems such as Waandenburg syndrome or Usher syndrome. Other causes that can cause deafness in the newborn are intrauterine infections or the side effects of some medications if taken during pregnancy. 80% of childhood deafness is present at birth and 95% of deaf children are born in families without a history of deafness.

Risk factors for deafness in children

There are factors that make it necessary to screen for deafness when the child is born and these are children who must be closely followed by the Pediatrician and their parents. Risk factors in the newborn are: family history of deafness, intrauterine infections (cytomegalovirus, rubella, syphilis, toxoplasmosis or herpes), head and neck malformations, severe hyperbilirubinemia, prematurity and weight below 1,500 grams, Neonatal meningitis, taking ototoxic drugs during pregnancy, low APGAR score at birth, admission to the neonatal ICU with mechanical ventilation for more than 5 days, and genetic syndromes associated with deafness. Approximately 30% of deafness appears late when the child is older than two years. From the age of two, the observation of the child by parents and educators is essential to detect hearing loss early. Risk factors for deafness in older children are: recurrent otitis media or serous for more than three months, severe head trauma, delayed language acquisition, meningitis, or use of ototoxic medications.

Consequences of the delay in the diagnosis of deafness

There are consequences at several levels:

• Learning: the child has a delay in learning at school, shows no interest in activities and has difficulty memorizing songs or poems. The teacher may notice that the child is not able to remember the instructions that have been given, that he copies the attitudes of his classmates and that it is very difficult for him to learn new concepts. Normally, relations with the rest of the students are not good and they tend to isolate themselves.
• Language: its development is very slow or non-existent, it uses very simple linguistic structures and it is not understood when it speaks. You have diction problems and have trouble learning new words or telling a story. The child with a hearing deficit has trouble reading and writing.
• Social relationships: has a very short concentration period, it is difficult for him to maintain a long conversation, he does not participate in games with other children, he is often distracted, he is not entertained by movies or stories told, he says a lot "what?" It seems that he does not obey the orders that are given him verbally. These children are often labeled as very busy, disobedient, and distracted.

How is deafness in the newborn diagnosed?

Nowadays it is widely accepted that the detection of infantile hearing loss within the first month of life, diagnosing it at 3 months and starting treatment in the first 6 months, are essential to avoid or minimize important alterations in the child. The only way to achieve this goal is by introducing universal hearing screening to all newborns.

Two methods are used to assess the baby's hearing ability:

• Otoacoustic Emissions (OEA): assesses the functioning of the inner ear when it is stimulated. It is a very simple test that is used to screen for deafness in the newborn and should be performed on all babies at birth.
• Auditory Evoked Potentials (PEA): Examines the brain's electrical response to sound to assess whether the ear is working properly. It is the test that gives the definitive diagnosis.

The incorporation of the early detection of hearing loss in newborns aims to:

• Identify any hearing impairment from birth.
• Start early treatment and rehabilitation.
• Allow the best development of oral language.
• Achieve the integration of the child with hearing impairment.
• Improve their communication, intellectual, emotional, social development, school performance and their professional future.

Treatment

When the child is diagnosed with hearing loss, the treatment should be multidisciplinary with the collaboration of the pediatrician, ENT specialist, speech therapist, psychologist and hearing care professionals. Collaboration with the school and the help of deaf associations in each Autonomous Community is essential at the time of diagnosis. Treatment consists of early stimulation of the child, adequate speech therapy and hearing aid treatment using hearing aids or a cochlear implant.

Cochlear implants

A cochlear implant is an electronic device that can help deaf people hear. It does not restore normal hearing, but rather provides the deaf child with a useful understanding of environmental sounds and helps him understand speech. That is, it has a completely different function to a hearing aid, whose function is simply to amplify sounds so that the ear can detect them. Cochlear implants directly stimulate the auditory nerve, avoiding the damaged ear, so hearing through a cochlear implant takes a learning period. The implant has two parts: an external one that is placed behind the ear, and an internal one that is placed under the skin through a small surgical procedure. This complex device comes equipped with:

• Microphone: picks up the sounds of the environment
• Speech processor: selects and organizes the sounds the microphone picks up
• Transmitter and Receiver / Stimulator: Receive signals from the speech processor and convert them into electrical impulses
• Electrodes: collect stimulator impulses and send them to the auditory nerve

Children who can receive cochlear implants are those with severe hearing difficulties; the most appropriate thing is to implant it as early as possible. This device will provide them with the ability to converse without the need for sign language or lip reading.