Can the visual performance of visually-impaired individuals be improved by colour?

Penny D’Ath

Introduction

The Royal National Institute for the Blind estimates that as many as 2 million people in the UK are affected by some form of visual impairment.  The three most common causes of visual impairment are age related macular degeneration, glaucoma and diabetic retinopathy, accounting for approximately 40%,13% and 8% respectively of those registered as visually impaired in the UK.  Diabetic retinopathy is the largest cause of visual impairment in the working population.

Some studies support the view that tinted lenses and filters may be of benefit to some patients with visual impairment, however, others have failed to find any significant improvement in visual performance with tinted lenses.

The aim of this project is to determine if real world reading performance can be improved by optimising VDU colour background in patients with various types of visual impairment.

A pilot study has been completed to determine visual performance tests and colour selection software, and these have been tested on a group of normals.  Preliminary indications suggest that a significant proportion of computer users benefit from customising the colour of their screen in terms of a reduction in asthenopic symptoms.  These early results may have major implications for the productivity of those patients presenting to optometrists with asthenopic symptoms associated with VDU use.

Methodology

In the current study involving visually impaired subjects, a series of visual performance tasks will be conducted testing the different skills required for reading including spreadsheet analysis, rate of reading assessment and use of nonsensical sentences (where the subject has to read and identify if the statement is true or false).

These tests will be performed on a white background to obtain a baseline score for each subject and then the subject will run through a computer generated algorithm to select their preferred screen colour.  The performance tests will be repeated with the selected colour and the results analysed to determine whether there is any improvement in performance with the preferred screen colour.

Sample Group

Subjects attending the City University Fight for Sight Optometry Low Vision clinic will be invited to participate. The researchers are aiming to recruit 20 subjects to each of the following ocular pathology subsets: age related macular degeneration, glaucoma, diabetic retinopathy and retinitis pigmentosa.

Outcome

It is hoped that this study will identify whether visually impaired patients may benefit by changing VDU screen background and if so, whether particular colours are of benefit to specific pathologies. This will enable optometrists to give appropriate advice to their patients.