What is Colorimetry?
Colorimetry is the use of different coloured filters to relieve the symptoms of visual discomfort and visual stress that can occur in an individual. These coloured filters can come in the form of coloured overlays or specially tinted spectacle lenses.
What is Visual Stress?
Visual Stress, otherwise known as Meares-Irlen Syndrome, is a term used to describe visual discomfort and perceptual distortions in printed text. The symptoms of visual stress most commonly arise when someone with the condition is reading a paragraph of high contrast black text on a white background. This is because the light reflected from a white page contains all the different wavelengths of light that form the visual spectrum. In visual stress, the brain struggles to process the full spectral of light.
What are the symptoms of visual stress?Common symptoms of visual stress include:
- Movement of printed text
- Blurring of print Letters changing in size or shape Patterns in the print (sometimes described as ‘rivers’ or ‘worms’)
- Halos of light surrounding letters
- Tiring easily whilst reading
- Skipping of words and lines
- Re-reading letters and words
Adults and children can both suffer with visual stress, however it is mainly identified in school-aged children. Early diagnosis is essential in young children as the longer it takes to identify and find a remedy, the greater the loss of confidence and self-esteem the child will experience in their reading abilities.
Individuals often confuse dyslexia and visual stress though the two can co-exist. Dyslexia is a learning difficulty which causes problems with reading, writing and spelling. Colored tints can often help dyslexic children though there may be no associated visual stress.
In order to be able to diagnose Visual Stress, an Overlay Assessment and rate of reading test is required.
How does a Colorimetry Test Work?
It is recommended to undertake a Routine Sight Test prior to conducting a colorimetry test. An average eye test provides the basis for vision correction and symptom relief.
After concluding that the symptoms of visual disturbance a patient is going through are not the result of something that can be corrected solely using a normal spectacle lens, a Coloured Overlay Assessment is recommended.
A series of coloured filters are shown to the patient and then a Wilkins Rate of Reading Test is carried out to assess if the coloured overlay improves the overall reading ability of the patient. The patient may then be prescribed a specific coloured overlay and asked to return in a few weeks noting any changes or improvements to their symptoms of visual stress.
Whilst coloured overlays are useful when reading from a book, tinted lenses are more convenient when copying from the board or another book or for those who are particularly light sensitive.
Following the successful use of a coloured overlay for a trial period, the Intuitive Colorimeter - a more specific colorimetry test may be used. At this appointment which normally takes 20-30 minutes, the optician will find the exact hue (colour) and saturation (brightness) that provides optimum relief of visual stress symptoms. This piece of equipment is able to prescribe up to 100,000 colour combinations and is therefore much more precise than a coloured overlay.
The final colour will be specific for each individual’s needs and is prescribed as appropriate in spectacles that can be worn as required (either solely for reading or more often as advised by your optometrist).
Who can have a Colorimetry Test?
Any individual suffering from the symptoms typical of visual stress should book a colorimetry test. Visual stress could also be the reason why a child is struggling to progress with reading at school.
If you, your child or someone you know is suffering from discomfort when reading, has visual triggers, patterns in print and an overall poor comprehension of their reading material, or experiences any trouble with reading that even spectacles cannot correct, a colorimetry test is strongly recommended.
Book a Colorimetry Test at Eye Emporium
The first step to take when having a colorimetry test is to have an up to date regular eye test.
The Coloured Overlay test can then be conducted and is offered in most Eye Emporium stores.
Once an improvement is seen in the patient’s ability to read and their overall comfort when reading, a Colorimetry Test with the Intuitive Colorimeter can be conducted at our flagship store in Stratford.
For more information and to book in an appointment do not hesitate to call in at any of our stores.