The Importance of Regular Eye Examinations for People with Learning Disability
“Why should my child have their eyes tested? – They seem to see OK.”
“This individual cannot read the letters so won’t be able to have an eye test.”
“Jane has autism and would not sit still or cooperate with an eye test”
“Andrew cannot communicate verbally so you won’t be able to test him”
All of these statements are often heard by eye care professionals who examine people with learning disability and yet 90% of these people can be examined in a normal high street optometrist’s practice with some adaptations to the routine tests and a sympathetic practitioner; the other 10% can be examined using more specialised tests, multiple visits to build confidence, and in a few cases multidisciplinary working with optometrists, ophthalmologists, orthoptists, and the rest of the health care and educational and social care teams.
Why is it important for people with learning disabilities to have an eye examination?
90% of our sensory input comes from vision, so in order to learn, communicate, and get around, it is important to be able to see clearly. If there are any restrictions to an individual’s vision then it is important to correct these (where possible) to allow normal visual development and learning to take place. Sometimes a defect in vision cannot be corrected, for example damage to the visual pathway caused by brain injury, which is quite common in people with moderate to severe learning disability. In these cases it is important that parents, teachers, and other carers know the nature of the visual problem, so that the necessary adaptations can be made to the living and learning environment. On more than one occasion we have encountered people who were thought not to be progressing due to their learning disability (e.g. changing from a speech synthesiser with 8 buttons to one with 32) only to find that their vision was hindering progress.
Is an eye examination more important if an individual has a learning disability?
Studies both in the UK and around the world have shown that up to 66% of people with learning disabilities have some visual problem. 14-20 % may be classified as blind or partially sighted, 15 - 30% may have defects in their vision which cannot be corrected with spectacles. For example, people with Down’s Syndrome have a far higher need for spectacles than the general population and the proportion of this group who need strong spectacles (both for shortsightedness – myopia, and longsightedness – hyperopia) are far higher. People with Down’s Syndrome and cerebral palsy are more likely to have reduced accommodation (the ability of the eye to focus on near objects), and everyone with learning disability is more likely to have a squint (turning eye) or lazy eye than the rest of the population. The presence of structural defects in the eye due to developmental abnormalities and disease associated with various syndromes are also more common in people with learning disability.
My child would never keep glasses on even if they did need them!
Studies have shown that only 2% of people with learning disabilities who have a significant need for glasses fail to wear them. Sometimes an adaptation programme is needed to desensitise individuals to the sensation of spectacles on the nose, and the change on visual perception caused by the lenses, but in the majority of cases if the person can see better then the spectacles are worn.
How can an eye test be done if someone can’t read the chart?
If someone is unable to read letters they are often able to match them against a ‘clue card’ with 5 or 6 letters on it. Sometimes lines of letters are used sometimes single letters. (e.g. Sheridan Gardiner test). If letters are not recognised then we use pictures either asking the patient to name or match the pictures (Kay Pictures). If the person cannot name or match symbols or letters then a technique called preferential looking is employed. This relies on the fact that if an individual is given the choice between looking at a blank sheet of card or one with a pattern on it they preferentially look at the one with the pattern. The examiner presents cards to the patient, which have a pattern at one end and are plain grey at the other, then observes which way the patient looks when presented with the choice, recording whether the pattern was seen. The size of the pattern is then reduced until no preference is detected. This technique was initially used for examining infants (Teller Cards), but was refined by Dr Margaret Woodhouse at Cardiff University who developed Cardiff Cards.
Of course in a number of people no responses to any of these tests can be obtained and observation of responses to different stimuli, behaviour in various environments, and an assessment of the structure and likely function of the eye and visual pathways is needed to estimate likely visual potential. These cases can prove the most challenging and often require multidisciplinary assessment to confirm findings.
Kay Pictures
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Sheridan Gardiner Matching Test
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Cardiff Cards - a preferrential looking test
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How do you test for glasses in people with no verbal responses?
A technique called retinoscopy is employed. This allows the optometrist to work out the strength of lens needed, and whether someone is longsighted, shortsighted, or has astigmatism just by shining a light in their eyes and inserting various lenses to ‘neutralise’ the apparent movement of the reflected light from the retina. In some patients to increase the accuracy of this test drops are instilled in the eye to prevent unwanted focussing of the eye during the examination (Cycloplegic examination). Using a variation of this test the focussing power of the eye (accommodation) can also be assessed (Dynamic retinoscopy). In some cases an instrument called an autorefractor can be used instead of a retinoscope. This is a computerised version of a retinoscope and can sometimes be helpful, but a degree of cooperation is needed from the patient which may sometimes either prevent its use or give inconsistent results. From the results of these tests spectacles of the correct strength can be prescribed.
Where should we go for an eye test? What will it cost?
There is no charge for an eye examination for children under 16 and under 19 in full time education. The fee is paid by the NHS. Anyone who is on income support is also eligible for an NHS examination. There are other exempt groups.
All optometrists working in high street opticians practices should be able to examine people with learning disabilities, and certainly those with a mild learning disability should have no problem finding a suitable practitioner. People with moderate to severe learning disabilities, or those with challenging behaviour can sometimes need a different approach to achieve a successful outcome. Charities such as SeeAbility in cooperation with Royal National Institute for the Blind (RNIB), are developing a list of optometrists who are interested in examining people with learning disability, and who would have contacts with other professionals in arranging referrals and multidisciplinary assessments.
Many of the optometrists at Linklaters and Leslie Warren are familiar with examining patients with learning disabilities, however if you feel there are likely to be any difficulties such as access to consulting rooms with wheelchairs, need for extended examination times, unfamiliarity or fear of strange environments then please contact our team for further advice.
Case Study : Faisel age 13
I was asked by a specialist worker in learning disability and visual impairment to carry out visits to two schools one afternoon, to examine five children where teachers had expressed concern, and where no other eye examinations had taken place.
Faisel was 13, a well built young man with severe autism. He had no verbal communication and at times challenging behaviour, using his physical strength to get what he wanted! The school records showed that whenever school eye screening tests had taken place, ‘unable to examine’ had been recorded. Teachers had become concerned as he seemed to becoming more withdrawn, had developed a head down posture, and was less confident with his mobility.
Faisel was seen in a small classroom accompanied by his favourite learning assistant and the specialist worker. He was sitting with his head down constantly tearing up pieces of paper, which was his normal response to stressful situations. Initial attempts to look at Faisel’s eyes were met with a threatening response due to invasion of his personal space and his anxiety. We sat and chatted for 20 minutes or so, made tea, and after a few biscuits, Faisel relaxed enough to start to become curious about some of the toys and equipment in the room. Gradually we were able to carry out some basic tests of visual function, and I became concerned that something serious could be wrong with his eyes. In order to look into Faisel’s eyes it was necessary to build his trust further and get closer to him, and it became apparent that I would need to use some drops to dilate his pupils to gain an adequate view. We would also need a darker room.
Parental consent was required to use the drops and unfortunately Faisel’s mother did not speak English as a first language so we also needed an interpreter. These challenges were soon overcome and the headmaster’s office was employed as a temporary consulting room. The view, or rather glimpses, I obtained of the inside of the eyes raised suspicion further, and I was becoming more concerned that there was possibly a retinal detachment. However due to the environment, the equipment available and by now Faisel’s understandable inattention, I was unsure. We therefore arranged for Faisel to come to the practice the next day with his parents and sister.
Considering the abnormal environment, Faisel cooperated well with the examination allowing confirmation of retinal detachment in his right eye, but no examination of the other eye was possible. A phone call to a friendly ophthalmologist at the local hospital resulted in Faisel attending immediately; and after giving up her lunch break and several hours of clinic time, the detachment in the right eye was confirmed and emergency surgery with a vitreo-retinal specialist arranged. Under general anaesthesia the retinal detachment was repaired, and examination of the other eye revealed the presence of a detachment in this eye as well.
Faisel continues to do well at school, and whilst he now has some degree of visual impairment he is able to socialise and navigate well. Without intervention by teachers who noticed the behavioural change, the specialist worker who confirmed their suspicions and arranged for my visit, and all the other eye care professionals involved Faisel would have had to cope with blindness as well as his learning disability for the rest of his life.
And the other 4 children…well they were examined on another day!!
Other Useful Websites:
Information on eyecare for people with learning disabilities www.lookupinfo.org
The Royal National Institute for the Blind www.rnib.org.uk
Special Olympics www.specialolympics.org |
