The entire peripheral area that can be seen by an eye looking straight ahead is known as the visual field. This aspect of vision is a crucial measure of the entire visual process from the eye to the brain. It is important because children sometimes have eye conditions such as glaucoma, or tumours in nerves or the brain that affect it, and if we could accurately measure the visual fields it would be extremely useful in diagnosing and assessing these conditions.
However, measuring visual fields accurately usually requires a person to concentrate looking at one central point only and indicate when peripheral lights are seen; this must be done reliably and consistently without the patient moving their eyes around. This is, understandably, too difficult for younger children, whose concentration may be limited and who may not be as compliant with instructions, as older children.
Crazy Castle equipment used for visual field test
We noted that one activity that does hold a child’s attention and compliance extremely well is playing computer games. In our research we were able to harness that potential by developing an entire purpose-built interactive computer games console and software for children to enjoy and play, that at the same time works out if they have any deficits in their visual field. In this short film we present and demonstrate a working prototype. It involves a toy castle with magic glasses on one side. When the child is well positioned, through the glasses they see a drawbridge opening to reveal a computer screen, presenting a game that they play by squashing mutant tomatoes and zapping naughty ghosts. Whilst the child is simply having fun the computer is monitoring their every response to assess whether there are any field deficits. Amazingly, we have been able to show that it is possible to measure fields in children accurately, whilst they are simply enjoying playing games.
In future projects we will use the comments made by children, and their parents, as part of developing a final working version. We will then prove its accuracy by testing it on a wide range of children and demonstrating the consistency of the system by testing and retesting on the same patients within a short period of time.
The project has been developed at Manchester Royal Eye Hospital, NIHR Biomedical Research Centre and
NIHR Moorfields Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust
and UCL Institute of Ophthalmology