Visual Impairment

A child is partially sighted if visual acuity is less than 6/18 and therefore educational aids such as large print books can be used. A child is defined as blind if visual acuity is <3/60 and therefore education can only be provided by methods such as Braille that do not involve sight.

Prevalence

1 in 2500 children are registered blind or partially sighted and 50% have additional functional impairments.

Aetiology

The commonest causes are optic atrophy, congenital cataracts and choroidoretinal degeneration.

Clinical Features

The eyes of visually impaired children may look abnormal or there may be unusual movements. When children are visually impaired from birth, their psychomotor development is altered. Early smiling is inconsistent and they do not turn towards sound. Reaching out for objects and the development of a pincer grip is delayed. Although early language may be normal, the development of more complex language may be slower. ‘Blindisms’ (eye poking, eye rubbing and rocking) may occur. Hearing deficit or severe learning difficulties are commonly associated problems.

How Visual Impairment Presents

In neonates the diagnosis is suspected if cataracts, nystagmus or purposeless eye movements are present. Otherwise it may be identified by parents or through child health surveillance. If there is any suspicion of visual impairment, an ophthalmological examination is required which may involve visual evoked response (VER) testing.

Management

Early intervention needs to focus on developmental progress, reducing blindisms and increasing parental confidence. Expert teaching assistance for educational support is needed to advise on approach to learning, mobility and support services.

Growing Up with Visual Impairment

Parents need advice on how to care for their child, adaptations for the home and how to provide stimulation in a non-visual way. Mainstream preschool is usually appropriate with support. Beyond this, placement depends on learning abilities and may be at mainstream school, a partially sighted unit or school for the blind. Mobility training is an important aspect of education.

Hearing Impairment

Prevalence

Four per cent of children have hearing deficits. Most are mild but 2 per 1000 need a hearing aid and 1 per 1000 needs special education.

Aetiology

Most mild to moderate hearing loss is conductive, and is secondary to otitis media. Sensorineural deafness may be genetic, may result from pre- or perinatal problems or follow a cerebral insult.

Factors that Increase the Risk of Deafness

How Hearing Impairment Presents

Universal neonatal screening with otoautistic emissions (OAE) is now being introduced to identify congenital sensorineural loss. Audiological testing should be requested for children at risk (see above), any child with significantly delayed or unclear speech or where there is parental suspicion of deafness. Investigations may include brainstem evoked responses (BSER) if the child is young or unable to cooperate.

Clinical Features

Hearing impairment may manifest itself in a number of ways:

• A lack of response to sound
  
• Delayed speech
  
• Behavioural problems
  
• Associated problems: learning disabilities, neurological disorders, visual deficits.

Management

Grommets are inserted in children with persistent conductive hearing loss. Hearing aids are fitted for sensorineural deafness, and early speech therapy is needed to develop communication. Cochlear implant surgery may be considered for moderate to severe sensorineural deafness. Genetic counselling may be needed.

Growing Up with Hearing Impairment

Parents need to learn to communicate with the child, which may include sign language. Moderately deaf children can attend mainstream school. Severely deaf children require specialist education in a hearing unit attached to a mainstream school, or at a special school for the deaf. Deaf children have a higher risk of psychological developmental disorders.