Vision rehabilitation

Recruiting research participants to assess vision therapy

Over the last year and a half we have been busy developing a computer game for young people with visual field loss caused by brain injury that builds on neuro-rehabilitation training programmes involving specialised computer software. These training programmes have been assessed in adults and significant improvements in functional vision have been observed, improving skills of independent living and quality of life. However, these training programmes are typically tedious and time-consuming so we have been exploring the potential of using computer game technology to increase motivation and engagement with rehabilitation. Now, we want to assess whether the computer game we have developed can improve the way in which young people with visual field loss use their vision and assess whether similar functional improvements occur that transfer to activities of daily living.

Jade-jonathan-300roundIf you have visual field loss or care for someone who does, and are between the ages of 8-25 years old, then we would like to invite you to take part in this research study. The study is sponsored by the University of Lincoln and the WESC Foundation in Exeter. Please contact Jonathan Waddington from the Research and Development team on 01392 454349 or email jwaddington@wescfoundation.ac.uk if you are interested and would like more details.

Functional vision and hemianopic alexia

A recent article in the British Journal of Ophthalmology has reviewed the results of published studies investigating how we might best help children with visual impairment who also have a condition affecting their neurodevelopment (Williams et al., 2014)*. They found strong evidence to support the effectiveness of providing spectacles to improve distance or near vision, and to support the use of ultraviolet light (as opposed to normal white light) as an environmental modification during visual training exercises. They also found suggestive evidence to support specific training strategies for improving acuity and the efficiency of eye movements. What was less clear was evidence to suggest whether the improvements in visual skills observed in the lab transfer to general skills and daily activities: something we refer to as functional vision.

The debate about whether or not rehabilitation strategies for visual field loss are effective often centers around the mechanism of effect, and whether observed improvements are the result of changes in the actual visual field (e.g. restoration of neural pathways) or the result of functional changes (e.g. compensatory eye movements). It is important to understand the mechanisms that may underlie rehabilitation, and the evidence that significant improvements can be observed is still controversial. However, it is equally important to determine whether any clinical improvements that we do see will translate to useful improvements in vocational, educational and daily-life activities (e.g. reading or mobility), and lead to a general improvement in quality of life.

ReadRightReading is one skill in particular that visual field loss can impact on in a variety of ways, depending on the location and size of the visual field loss. For those reading English (and other languages read from left to right) it may be difficult to locate the next word on the same line if you have a right-sided visual field loss, and it can be difficult to locate the start of the next line if you have a left-sided visual field loss. When the field loss includes an area of the central field called the macular region there is often a corresponding loss of visual acuity and reading small text becomes more difficult.

The evidence for improvements in reading ability after vision rehabilitation is variable but suggests positive outcomes that depend on the specific training program, and on the specific area of the visual field loss. For those interested in therapy options for patients who have difficulty reading as a result of visual field loss you may wish to visit University College London’s Read-Right website, where they offer a free web-based therapy for patients with hemianopic alexia. Patients can register to join and use the service here.

 

*Cathy Williams is a consultant senior lecturer at the University of Bristol, and paediatric consultant at Bristol Eye Hospital. She will be working in collaboration with us at the WESC Foundation and the University of Lincoln to help with participant recruitment for a study that we will be running later in the year to investigate whether eye movement training using computer game software may be beneficial for young people with visual field loss.

Vision 2014 and the WESC Foundation international conference

This April I’ll be presenting at two separate conferences: Vision 2014 and the WESC Foundation’s annual international conference.

Vision2014_logoVision 2014 is the 11th International Conference on Low Vision, which occurs once every three years and this year will take place in Melbourne, Australia. The themes of the conference are Advancing research, upgrading practice, and improving participation. I will be giving a rapid fire oral presentation about our current research project: “A computer game designed to improve sight for children with visual field loss.” as well as presenting a research poster at the exhibition.

The draft program for the Vision 2014 conference looks particularly promising with an entire day set aside for neurological vision impairment, and other symposia include updates on low vision technology, bionic implants and rehabilitation delivery.

The WESC international conference will be taking place onsite at Exeter, UK on the 30th April and 1st May with a followup day on the 2nd May to discuss a specific neurological visual impairment: Batten disease, also known as neuronal ceroid lipofuscinosis. The first day will have talks from Dr. Christine Roman-Lantzy on the CVI Range (which is an approach to assessment and intervention for children with neurological vision impairment) as well as a presentation on the Children & Families bill from Claire Dorer of NASS. On the second day we have presentations on the implications of visual impairment after stroke from Dr. Fiona Rowe of the University of Liverpool, and a presentation from Prof. Rob Scott on developments with the Brainport. If you are interested in finding out more details about this conference and would be interested in attending please feel free to contact WESC using the email address: kgaulton@wescfoundation.ac.uk.

Hopefully I will see some of you there.

Computer game for visual field loss rehabilitation: Introduction

The week before last I was in Lincoln to visit the University and give a presentation on the progress we have been making with our research at the WESC Foundation to the School of Psychology’s Perception, Action and Cognition group. I talked about some of the rehabilitation strategies used for people with low vision and about our project to develop a computer game that could be used for rehabilitating people with visual field loss.

Picture1The premise of our game is centered around the “visual search task”, which involves finding a target object in a visual display of distracting objects. In the picture on the right the distracting objects differ from the target by one feature only: colour (i.e. the target object is a green square and the distracting objects are orange squares). Simpler tasks involve finding a target that differs from the distracting objects by more than one feature (e.g. colour and shape: the target is a green square amongst orange circles). More complicated tasks involve multiple groups of distractors that share different features with the target (e.g. the target is a green square amongst orange squares and green circles).

Previous research has demonstrated that adult stroke patients with visual field loss such as hemianopia can train using visual search tasks to improve their functional vision. The mechanism for this rehabilitation is unclear and may depend on developing new eye movement strategies (compensatory visual scanning), improving visual perception and attention (perceptual training), or restoring small areas of the visual field (visual restitution therapy). However, typically visual search tasks are quite dull and unable to engage people for the long periods required for the rehabilitation to generate a significant improvement in vision. Our project aims to improve engagement and motivation by implementing the visual search task as part of an interactive computer game.

 

Picture2

The game is still early in development and we are constantly involving potential users in the design process for input and feedback so it is all subject to change. At the moment there are three levels of gameplay: short-term, mid-term, and long-term. Short-term gameplay consists of immediate reward for finding the correct target in the visual search task such as sound and particle effects. Mid-term gameplay consists of adding some meaning to the visual search task. In the image above, the player has to find the target objects to progress passed a river of lava. Long-term gameplay consists of adding an element of progression to the game. In the current version of the game the player has to make their way through twelve different levels to reach the boat that will allow them to escape the island and complete the session for that day. As rehabilitation can take many weeks there will also be an additional extra-long-term (or replayability) element, which consists of a calendar that can visualise progress over time.

It is important to determine whether using computer game technology to make rehabilitation more engaging is a viable and effective strategy for young people with visual field loss as well as for adults. We intend to perform a pilot study next year to test the efficacy of the game as a rehabilitation tool and determine what effects the rehabilitation has on functional vision and whether these skills transfer to natural tasks and have a real impact on patients’ quality of life.