Hearing loss can present in different ways depending on the age of the child. Hearing loss in neonates is almost exclusively picked up via newborn screening programme assessments. In older children, parents or other professionals such as school teachers, may notice delayed language skills, behavioral problems or listening to the television at raised volumes. In the history, it is important to ascertain whether there are any associated otological symptoms such as otorrhoea, otalgia, tinnitus, or vertigo. A thorough history is required including asking about any other neurological symptoms, medical history including drug history and precipitating events such as trauma, recent viral infections or new medications.

The examination will involve assessing the ear including the appearance of the pinna particularly inspecting for any deformities such as microtia or anotia. Otoscopic examination of the external auditory canal and tympanic membrane is crucial, with special attention on the attic for cholesteatoma. An examination should also include assessment of cranial nerves, a full neurological assessment, and assessment of balance depending on the age of the child.

With the implementation of Universal Newborn Hearing Screening program, today most patiets are identified within a few months after birth, with intervention started by 6 months.

Hearing assessment in children is age and ability dependent and will be addressed per age group here.[9]

Neonates

Otoacoustic Emissions

In the UK, all newborns and those who require less than 48 hours of special care in neonatal intensive care (NICU), are offered evoked otoacoustic emission (OAE) testing within the first 4-5 weeks of birth as part of a Newborn Hearing Screening Programme.[9] Oto-acoustic emissions are outer hair vibrations that are detected in the external auditory canal in response to a click stimulus. This test is easy to perform and does not involve a general anesthetic.

Automated Auditory Brainstem Response

This investigation is offered to all newborns who have spent over 48 hours in the neonatal intensive NICU and is also offered to those who do not pass two OAE tests.[9] It involves measuring brainstem electrophysiological responses to click stimuli using electrodes placed on the scalp. This assesses hearing throughout the entire hearing pathway; form the external ear through to the brainstem.

6-8 months                                               

Distraction techniques

An assistant engages the child’s attention, and the tester, whilst placed behind and to the side of the child, makes sounds of different intensities. The child is assessed to see whether they turn to the side of the noise.

9 – 36 months

Visual Reinforcement Audiometry

The child is placed at a table with some toys with two speakers either side that produce sounds. If the child looks towards the speaker playing a sound they are delivered a visual reinforcement (such as a flashing light).[10]

24-60 months

Conditioned Play Audiometry

The child is conditioned to perform a task in response to an auditory stimulus such as placing a ball in a cup. Once the task is learned the sound volume is reduced in order to determine their hearing threshold.

Over 60 months

Pure Tone Audiometry

A 5 years of age most children can undergo pure tone audiometry. Hearing thresholds are determined by presenting sounds of various frequencies and at various intensities until the quietest sound is reliably detected 50% of the time. This test requires a higher level of attention and therefore is rarely done below the age of 5 years.

Other investigations

Additional investigations will be tailored to the precise clinical picture. In syndromic children, chromosomal testing is advised. There is also a role for imaging in the form of either computed tomography (CT) or magnetic resonance imaging (MRI)

Some authors advocate measurement of renal function and testing for connexin-26, which is a marker who sensorineural hearing loss. In some children, imaging studies may prove useful and detect abnormalities of the cochlea or the cochlear nerve. Finally, ECG may be useful in children with Jervell Lange Nelsen syndrome. The ECG will reveal a prolonged QT interval, which can lead to syncopal attacks and death.

Treatment for hearing loss depends on the type of hearing loss present, the underlying cause and often there is an element of patient/parent preference.

Conductive hearing loss due to otitis media is treated with antibiotics. Some children may benefit from a myringotomy tube. Sensorineural loss cannot be treated with medical measures. Mild cases may be treated with amplifcation aids and speech therapy is useful. However, amplifcation of sound can result in ear pain and discomfort.

Conservative management

A key element to managing hearing loss in family support and advice. There are a number of behavioral measures that can be used to improve hearing without the need for adjuncts or surgical intervention. The principles of this are rooted in creating a deaf-friendly environment such as limiting background noise, talking face-on, and clear intonation. There are also a range of hearing assist devices that can be used such as television listeners. It is also crucial that the child educational support which could be in the form of special equipment or positioning in the classroom.

Hearing Aids

There are a variety of hearing aid types that are used in specific situations. Each type will be briefly covered here.

Binaural air conduction hearing aids rely on at least a partially functioning inner ear and central auditory processing system. They work by converting sound detected by a microphone into digital signals which can then be amplified and re-converted into audible sounds that are transmitted to the ear. They can be classified based on whether these key parts are housed in an earpiece that sits externally (behind-the-ear), inside the canal (in-the-canal) or further inside the canal (in-the-ear). 

Bone conduction hearing aids are used typically in a conductive hearing loss when there are ear problems that impede the use of a regular air conduction hearing aid such in children with external ear deformities (anotia, microtia) or when there are chronic ear infections. Bone-anchored hearing aids (BAHA) are fitted surgically under general anesthetic over two stages. A titanium implant is fixed into the temporal bone. Through this setup, a sound is conducted directly to the inner ear by way of the bone, bypassing the middle ear. Typically the BAHA is fitting from 4 years of age once the temporal bone has developed, however, soft-band bone conducting aids can be used from several weeks of age.

Contralateral routing of sound (CROS) hearing aids are used when there is a unilateral sensorineural hearing loss. The sound in the problem ear is diverted to the better hearing ear without amplification. In cases where neither ear has normal hearing but one side is significantly better, a variation on this can be used called a BiCROS.

Cochlear Implant

Cochlear implants work by converting sound into digital signals that are transmitted directly to the auditory nerve via an electrode array. In the UK, the National Institue of Clinical Excellence (NICE) recommends cochlear implants in children who have severe to profound deafness in one or two ears with minimal benefit from conventional hearing aids after 3 months of use.[11]

Other options

Ventilation tubes are indicated in conductive hearing loss secondary to flue ear, or less frequently in the context of recurrent otitis media. They are inserted surgically and typically self-extrude on average a year of insertion. Children found to have cholesteatoma invariably require surgical clearance of disease via a mastoidectomy.

• Acute otitis media

• Cholesteatoma

• Congenital stenosis

• Exostoses

• Foreign body

• Hemotympanum

• Impacted cerumen

• Keratosis obturans

• Middle ear tumour

• Otitis externa

Prognosis of hearing loss will vary considerably based on the underlying aetiology. Congenital sensorineural hearing loss left untreated will invariably not improve or can progress, such as in the case of congenital CMV. On the other side of the spectrum, glue ear shows an excellent prognosis with resolution of symptoms even without intervention.[12]

Hearing loss in the pediatric population must be managed as part of an interprofessional team. Most children with hearing loss are otherwise normal but unfortunately, are often treated as if they are mentally dysfunction. Thus the key is awareness and education of the caregivers and the public. Parents should be provided with resources by the social worker where they can seek specialized help.

Today, many states have social workers and a hearing loss nurse or developmental nurse dedicated to providing caregivers with the best school environment, the best form of communication and the best resources. The nursing and audiology team should work with the clinicians to coordinate the cause of hearing loss and provide suitable treatment. Further, they should assist in patient education.

Other members of the team include medical doctors including otolaryngologists, audiologists, speech therapists, geneticists, and pediatricians. In addition to this, audiologists, speech and language therapists, educational psychologists and specialist nurses are vital parts of the wider team.

Communication is the most significant loss in people with deafness. Communication is vital for integration and socialization into society. Thus, every effort must be maintained to reverse the hearing loss. Today, most deaf children are taught to lip read and/or learn sign language. In addition, the hearing loss nurse should provide parents with information on devices like strobe lights connected to alarm clocks, doorknobs, and timers. Schools need to have a system so that the hearing loss child is able to hear any overhead announcements. All the latest TVs are now equipped with closed captioning.

Children who are deaf are at a high risk for abuse and thus a social worker should always follow these patients.

Delivery of the highest quality of care and support requires a coordinated approach amongst services including between primary and secondary care. It is important to identify hearing loss at an early age, because the earlier treatment is offered, the better the prognosis. (Level V)[13]