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Eccentric viewing and steady eye techniques.

This CET article highlights the use of the training techniques that can be employed to assist patients with visual loss. The methods are discussed along with the type of patients that are most likely to benefit from this approach. Further guidance is provided on how patients can access this specialist training.

INTRODUCTION

600,000 people are thought to be living with age-related macular disease (AMD) in the UK today.

With projections indicating that the number of cases of late AMD will reach 679,000 by 2020, a significant number of patients will be facing the news that they are developing signs of macular disease or will already be living with central vision loss. (1)

In addition to existing rapid access referral protocols where active wet disease is suspected, there is also a need to ensure that individuals with all forms of macular disease receive appropriate ongoing information and support. Timely support and advice means that an individual can better adapt and learn to cope with any reduction in functional vision, retain their confidence and independence, which in turn can reduce the incidence or severity of falls, depression and social isolation due to visual impairment.

Optometrists and dispensing opticians are in an ideal position to provide information on the condition, advise on modifiable risk factors such as smoking cessation, and on the availability of local and national services that offer both practical and emotional support whether provided by health, social care or the voluntary sector. To do this effectively it requires improved inter-professional and cross-sector working.

There is a growing awareness that better outcomes can be achieved with the development of person-centred services and a closer integration of health and social care services; this is reflected in the UK Vision Strategy. (2) The strategy is a cross-sector collaboration that sets out a framework for change for the development and delivery of excellent services where we all take greater responsibility for our eye health, avoidable sight loss is eliminated and individuals living with sight loss have a fully participative and inclusive part in society.

Strand 2 of the UK Vision Strategy is focused on the individual who has a sight-threatening condition or is experiencing sight loss, and on the integration of the relevant health and social care services. Everyone with an eye condition receives timely treatment and, if permanent sight loss occurs, early and appropriate services and support are available and accessible to all. Also embedded within the strategy are the 10 'See it my way' measures developed by people living with sight loss. (3) Person-centred holistic services must reflect what is important to the people using them.

In addition to the optimisation of vision following refraction and the provision of appropriate lenses, all optometrists and dispensing opticians, not just low vision practitioners, have an important role to play in providing a practical demonstration on how to effectively use task lighting, managing glare control and appropriate use of colour and contrast. All of these simple interventions can be of benefit even at the earliest stages of macular disease for most people.

Along with the obvious difficulty that macular disease causes with reading, it is important that we take into account the functional impact that the loss of fine detail and reduced colour vision has on everyday activities such as recognising faces, selecting colour coordinated clothing, setting temperature dials on the washing machine or oven, telling the time, shaving, applying make-up or nail cutting.

Referral to or provision of low vision and rehabilitation services needs to be offered as soon as there is a noticeable impact on an individual's daily activities, in parallel to any referral for treatment.

ECCENTRIC VIEWING AND STEADY EYE TECHNIQUES TOOLS IN THE BOX

As part of a person-centred low vision and rehabilitation package, eccentric viewing (EV) and steady eye strategy (SES) are practical techniques that can help many people with central vision loss use their residual vision more effectively. With training and practise it is possible for an individual to develop or refine these skills making it easier to perform daily activities such as:

* Preparing food and drink

* Walking safely by being more aware of hazards like the edge of a kerb

* Seeing photographs and recognising faces including their own face in a mirror

* Reading with improved speed, accuracy and fluency Watching the TV

* Telling the time.

Many individuals who have received training on EV and/or SES report a renewed interest in hobbies including theatre, gardening, painting and writing poetry. EV and SES are tools in the low vision and rehabilitation toolbox along with the effective use of lighting, LVAs, independent living skills, mobility and orientation training, leading to a better quality of life and improved visual functioning.

Eccentric viewing

Many people with macular disease naturally adopt eccentric fixation to a degree for distance objects but may not do so consistently or consciously for a wide range of tasks. For example, they may notice that they can see a friend's face or the television better when they are not looking directly at it but few people can translate this skill to near tasks without training.

The area or direction of gaze that the patient uses for occasional distance tasks is not necessarily the best position to use for near tasks such as reading.

In patients with bilateral central vision loss EV training may be a viable tool to help people use what remains of their vision. EV involves identifying an area of the retina that retains reasonable functionality, and is as close to the fovea as possible in order to maximise detail, and learning to use it effectively.

Not everyone with central vision loss will need to eccentrically fixate as it depends on the type and amount of damage or scotoma(s). There are five main types of scotoma and individuals may have one or a combination of these:

* Patients often describe a relative scotoma as 'misty' vision. In such cases the macula is working but at a reduced level. Lighting and magnification may be all that is required to help the individual, however, if the scotoma is significant, it may be beneficial to teach EV and SES techniques

* Absolute scotoma results in an absence of central vision. EV and SES, using an area of retina, which is closest to the fovea, might benefit the individual

* Oedema occurs when fluid builds up between the retinal layers and often results in wavy lines and distortion. If the distortion disrupts reading, EV along with SES may help an individual

* Ring scotoma is characterised by normal macular functioning at the very centre but is surrounded by damage. In these cases EV would not be appropriate, however, SES may assist with reading. Ring scotomas often close up as the disease progresses, so EV will remain an option to return to if required in the longer term

* Patients often describe multiple scotomas as 'patchy' vision, as sight loss has occurred in patches across the macula. These individuals tend not to benefit from high levels of magnification--simply making something bigger means less fits into the small area of foveal clarity, however, EV and SES may be of benefit.

How to identify the preferred retinal locus (PRL)

When training patients it is important to emphasise the functional, rather than the damaged areas of vision. Understanding they still have useful vision and how to use it is encouraging and motivational. Although it may be of interest to the practitioner to map the scotoma(s) this is not particularly helpful in terms of low vision and rehabilitation.

In every case, it is useful to start with a conversation where the individual describes their own vision and what they are having difficulty with; this conversation should help identify the type of scotoma and whether EV and/or SES are needed. It is important to ascertain which is the better eye, which isn't just dependent upon acuity but also the type and location of damage. Working with the better eye, the following methods can help to identify and then refine the PRL:

* Face-to-face--using one eye at a time, ask the patient to look straight at your nose and describe any parts of your face that are clearer or more distinct. From this you should be able to identify which is the better eye and the clearest area is the vision you will use as a PRL

* Clock face technique--ask the patient to imagine a clock around your face and report which area is clearer by reference to the clock number. The clock number reference not only helps to identify the vision you will use as a PRL but may help an individual to remember where their own PRL is (see Figures 1 and 2)

* Amsler grid--use an Amsler grid with diagonal lines and a dot in the centre. Work with the better eye and ensuring the patient wears their usual reading prescription. Avoid using bifocals and varifocals for this purpose as they may cause confusion as to which area is clearer. The patient should concentrate on the centre of the grid and describe the location of the clearest areas.

Eccentric viewing--using the PRL

Once the clearest vision has been identified, a person should be taught how to eccentrically fixate and use their new PRL. Should the individual describe the clearest area as being top right, in order to see things which are central they will need to look down to the bottom left in this case or using the clock face technique, the clearest area might be reported as at number one, thus an individual should look towards the number seven in order to see the central object of interest. When reading, instead of looking straight at the first letter of the text, the individual would need to apply the same principle. In the example given they would to look down and to the left of the first letter.

The next step would be to introduce SES--the individual should be instructed to keep their head still and without moving their eyes from the position (relative to the text) they should move the text from right to left, like a typewriter.

Steady eye strategy

Individuals with central vision loss often describe their experience of reading as 'words seem to come and go' or that when they are holding text they keep moving it trying to get it clear; both of these are indications that they might benefit from adopting SES as a means of improving accuracy and fluency when reading. The letter or word would normally disappear in patients with central vision loss when the movement of the eye places the scotoma over the word that is being read. The learned saccadic reflex is disrupted by a foveal scotoma but the brain still tries to utilise saccades when reading; this results in irregular (scribble-like) eye movements.

SES is a technique that specifically helps with reading and can be useful for many individuals with low vision, not just those with central vision loss. SES requires the patient to break the saccadic reflex by keeping their gaze still and scrolling the text through their functional piece of vision. The technique enables the individual to keep their place in the text and improve their accuracy and reading speed, although not to pre-macular disease levels.

During a standard appointment, practitioners are unlikely to have time to do more than introduce the concept of EV and an explanation of the face-to-face and clock face techniques. Follow up with the provision of further information on the techniques to the patient can be offered or the contact details provided of other agencies providing EV and SES training, for example, the local low vision service rehabilitation officers for the visually impaired. Practitioners are encouraged to advise the Macular Society if they offer EV and SES training. (4)

The Macular Society operates a Skills for Seeing programme, which provides free one-to-one coaching in EV and SES through a growing network of volunteer trainers, many of whom have central vision loss (see Figure 3). It also holds information about other providers of EV and SES coaching within the voluntary sector or health and social care. A Skills for Seeing leaflet is available and practitioners and patients can contact the Macular Society helpline on 0300 303 0111 for more information.

THE IMPORTANCE OF PRACTISE

It takes patience to fully utilise EV and SES and people with bilateral central vision loss will need encouragement to practise several times a day for a few minutes at a time after they leave the clinic. They should practise using everyday things they want to see, for example, photographs, letters or watching the TV. For reading it may be useful to start with larger print, such as the headlines, before moving on to smaller print, using a magnifier if needed.

DISCUSSION

The concept of training around EV and SES as a component part of a holistic low vision and rehabilitation package is not new with the first published paper on the subject written by Krister Inde and Orjan Backman in Sweden in 1975. (5)

Numerous studies have taken place since and there is not a single definitive model or approach to the delivery of EV and/or SES training. Different models and approaches and subsequently non-comparable outcome measures have evolved dependent on the service setting, funding and the professional background of those involved in the design and implementation of the service.

As would be expected it is difficult to isolate the impact of any one element of an intervention as there are many different factors that influence how an individual copes with and adjusts to sight loss including: level of acceptance, progression of condition, individual circumstances and social support network, availability and effectiveness of treatment options, use of non-optical and optical low vision aids, along with their motivation.

Some form of EV and/or SES training is widely available in the US, across Scandinavia and in parts of America. Prior to 2006, EV and SES training was rarely offered in the UK and there was no easy way of identifying where the few providers were. Since then the Macular Society has been striving to increase awareness of the potential benefits of EV and SES training as one element of low vision rehabilitation and supporting the further development of the evidence base.

A systematic review of literature evaluating EV and SES techniques was undertaken by Cardiff University for the Macular Society in August 2012 and highlighted that these interventions can improve reading ability and the capacity for participants with central vision loss to perform a wide range of daily living activities. (6,7)

The review also found that EV training is more effective than provision of magnifiers alone for improving near visual acuity in individuals with an absolute central scotoma.

Ideally, low vision practitioners, optometrists and dispensing opticians need to provide or enable access to EV/SES training prior to the issuing of magnifiers.

Course code: C-39845 Deadline: April 4, 2015

LEARNING OBJECTIVES

To be able to explain to patients about the use of specialist techniques to aid visual rehabilitation (Group 1.2.4)

To be aware of the availability of external resources for visual rehabilitation (Group 2.2.2)

To identify patients that may benefit from low vision rehabilitation and understand the availability of services for these patients (Group 4.2.2) To understand how to modify examination techniques for patients with severe visual impairment (Group 7.1.7)

LEARNING OBJECTIVES

To be able to explain to patients about the use of specialist techniques to aid visual rehabilitation (Group 1.2.4)

To be aware of the availability of external resources for visual rehabilitation (Group 2.2.2)

To understand the use of specialist techniques in visual rehabilitation (Group 4.4.1)

To recognise when it is appropriate to refer patients with impaired vision for additional support from specialist teams (Group 6.4.3)

LEARNING OBJECTIVES

To understand how to modify examination techniques for patients with visual impairment (Group 3.1.4)

KEEP INFORMED

The Macular Society offers a free professional membership, providing easy access to the full range of patient literature and updates on the latest developments in the field. If you would like to join as a professional member please register at http://bit.ly/1hByULd

INTERNATIONAL ECCENTRIC VIEWING CONFERENCE

The Macular Society is hosting an eccentric viewing conference at Aston Conference Centre, Birmingham on June 3, 2015. The conference gives eye care professionals the opportunity to hear from international experts in eccentric viewing and low vision. At least two CET points are available for optometrists and dispensing opticians. For more information see www.macularsociety.org/ evconference

Amanda Reeves is a dispensing optician with experience in both high street and hospital low vision clinics. Until recently she was the low vision services manager for the Macular Society having started with the organisation in November 2006. Ms Reeves was the organisational lead and expert technical advisor for all aspects of the Society's work relating to low vision and rehabilitation and responsible for raising awareness and dissemination of good practice amongst eye care professionals. Prior to this she worked for the RNIB as a low vision officer and trainer.
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Title Annotation:CET: ECCENTRIC VIEWING
Author:Reeves, Amanda
Publication:Optometry Today
Geographic Code:4EUUK
Date:Mar 7, 2015
Words:2854
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