BATOD
The British Association of Teachers of the Deaf
Promoting Excellence in Deaf Education

Is vision care and assessment crucial for deaf children and young deaf people?

Barbara Homer (NDCS) and Mary Guest (SENSE)

For more than five years the National Deaf Children's Society and Sense have been working together raising the profile of, and identifying the need for, good eye care for deaf children. Subsequently we have been collaborating with key people who work with deaf children, with parents, and essentially with ophthalmologists to produce quality standards and good practice guidelines on optimum vision care for the deaf child.

In 2002 we commissioned an evidence-based overview of ophthalmic disorders in deaf children. Over 1000 relevant research papers were identified, of which 190 were analysed in detail, and a summary of this research is being prepared. For more than 70 years, studies have repeatedly shown a high level of vision impairment among deaf children, but the differences in definitions and classifications of vision impairment make comparison between the various studies difficult.

Consistent findings show, nevertheless, that 30% to 60% of deaf children have a significant vision impairment. For example, Burdge (1933) found that 40% of deaf children tested needed spectacles, Braly (1938) reported that 38% out of 422 deaf children had less than 20/20 vision on the Snellen chart and, in a study in 1952, Stockwell found that of 960 deaf children 46% needed spectacles. In 1973, Alexander identified that out of 572 children, 35% had refractive errors and 22% had other ocular pathology, and Regenbogen & Godel (1985) showed, in a comparative analysis with the study by Coleman (1970) on 3,623 hearing children, that more than two and a half times as many deaf children had eye abnormalities.

More recently, in 1988 Rogers and others screened 360 deaf children and young people aged between 6-22 years for vision problems. Overall, 43% either had a significant refractive error or other eye abnormalities. They concluded that a deaf child is at greater risk of vision problems than a child who is not deaf and that a comprehensive examination should be performed at identification of deafness. In 2001, Brinks et al (2001) found significant ocular pathology in 111 (48%) out of 231 young deaf people. They concluded that deaf students had a high frequency of eye disease, that early diagnosis and treatment could improve their quality of life and that the potential benefits of ophthalmologic screening in deaf children is enormous. Lastly, in 2003, Guy et al showed that out of 110 children in southern Derbyshire who underwent ophthalmic assessment, 48 had ophthalmic abnormalities; and of the 82 children with uncomplicated deafness, 26 had refractive errors.

These higher rates of ocular pathology have been attributed to important elements of the eye and ear (eg retina and cochlea) maturing during the same embryological stage, from the same embryonic layer, which may be susceptible to genetic or environmental factors, and to environmental insults, such as hypoxia, toxic agents, viruses, meningitis, and other conditions which may affect both the eye and the ear.

If a deaf child has a problem with their vision it is essential that this is identified and treated as soon as possible. Those identified with ocular abnormalities will require long-term ophthalmological review. In 2001 Brinks et al found that this is often overlooked and that 63% of deaf students aged 10-22 had significant ocular pathology, but that they had not seen an ophthalmologist in the previous two years.

For the majority of deaf children, when an ophthalmic problem is identified, it is unlikely to be of a serious nature (as in Guy's study where, of the 75 ocular abnormalities identified, 47 (60%) were refractive errors such as astigmatism, myopia and hypermetropia). But more serious eye conditions (resulting in deafblindness) can create enormous challenges for the individual, particularly in relation to communication, information access, mobility and social inclusion.

Regardless of the seriousness of the eye condition, it is essential that each deaf child is assessed and supported by well-trained and well-informed staff who understand the child's individual needs. Specialist staff working closely with the child and family, such as Teachers of the Deaf or teachers working with those with multi-sensory impairment, play a crucial role in ensuring that eye assessment takes place at appropriate times in the child's development.

The optimum times for referral and assessment of eye care for deaf children and young people is clearly set out in the document 'the ophthalmic care pathway for the deaf child', and the key points are identified here:

  • At birth - as part of the routine screening programme
    Newborn babies will have their eyes examined as part of the routine screening programme and babies with identified disabilities should be routinely examined by the paediatric team for congenital abnormalities that may have ophthalmological or audiological implications.
  • At diagnosis of deafness
    As soon as a child is identified with a permanent hearing loss they should be referred for a full ophthalmic assessment.
  • At 2-4 years
    Children with bilateral profound congenital sensorineural hearing loss of unknown aetiology should be re-referred to the paediatric ophthalmologist for assessment. Ideally the child should be seen in the child development centre or specialist ophthalmic clinic where they can be accurately monitored and any relevant treatment or referral undertaken.
  • At 4 to 5 years - routine screening in the general child population
    The Child Health Sub-Group of the National Screening Committee recommends that all children have their vision screened by an orthoptist between the ages of four and five years of age, which will include an assessment of visual acuity. As part of this screening programme deaf children will have their vision assessed. This 'routine screen' may not, however, meet the additional needs of the deaf child.
  • At 7 to 9 years
    Children with a sensorineural hearing loss, where the cause of the deafness is unknown, should be re-referred to ophthalmology where they can be tested for Usher syndrome using electroretinography (ERG). An ERG can be performed at any age and there are a number of conditions for which this test is useful. While there is no guidance on the optimal age for testing for Usher syndrome, seven years of age is generally considered to be the most appropriate. A normal ERG at this age may not, however, exclude type II Usher syndrome.
  • At 10 years and above
    Since myopia may increase during the adolescent years, deaf children should have their visual acuity re-assessed at this age by an optometrist. If there are any concerns regarding night vision, field loss or visual loss that is not corrected by spectacles, the child should be referred for a full ophthalmological assessment.
  • At referral for cochlear implantation and other complex interventions
    When a child is referred to a specialist service, the specialist service should ensure that the child has had their vision checked. If there has not been an ophthalmic assessment they should arrange for the child to be seen by the ophthalmology service as soon as possible.
This 'long-awaited' document is being launched by NDCS and Sense on the 1 April 2004. The document will be evaluated and revised by 2008. Copies will be available from NDCS and Sense and it can also be downloaded from our respective websites from the beginning of April.

We very much welcome comment and feedback from professionals working in the field with deaf children and young people.

Barbara Homer is no longer with The National Deaf Children's Society

Mary Guest Sense, the National Deafblind and Rubella Association
11-13 Clifton Terrace
Finsbury Park
London N4 3SR
www.sense.org.uk

References

Alexander J C C (1973)Ocular abnormalities among congenitally deaf childrenCanadian Journal of Ophthalmology 8; 428-433
Braly K (1938) A study of defective vision among deaf childrenAmerican Annals of the Deaf 83: 192-193
Brinks M, Murphey W, Cardwell W, Otos M, Weleber R (2001) Ophthalmologic screening of deaf students in OregonJournal of Pediatric Ophthalmology & Strabismus 38(1): 11-15
Burdge A (1933) Conserving the vision of our deaf children International congress on the education of the deaf Proceedings: 500-502 Deafblind International Conference Canada
Coleman H M (1970) An analysis of the vision of the visual status of an entire school population Journal of the American Optometric Association 41(4): 341-347
Guy R, Nicholson J, Pannu S S, Holden R (2003) A clinical evaluation of ophthalmic assessment in children with sensorineural deafness Child: Care, Health and Development 29:377-384
Regenbogen L, Godel V (1985)Ocular deficiencies in deaf childrenJournal of Pediatric Ophthalmology and Strabismus 22(6): 231-233
Rogers G L, Fillman R D, Bremer D L, Leguire L E (1988) Screening of school-age hearing-impaired children Journal of Pediatric Ophthalmology and Strabismus 25(5): 230-232
Stockwell E (1952) Visual defects in the deaf child Archives of Ophthalmology 67:18

March 2004

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