What is Colorimetry and How Can it Help My Child?
Colorimetry is used to accurately prescribe tinted lenses to help people who have trouble reading because of visual perception problems: For some people, specific colours can be very effective in reducing visual stress. Prior to colorimetry, people often start using coloured overlays to assess the effectivity of using colour to help with reading. When found successful then colorimetry could be advised.
What is Visual Stress?
Visual stress, sometimes called scotopic sensitivity or Meares-Irlen Syndrome, is a sensitivity to visual patterns: This can cause visual perceptual problems which interfere with reading. People who suffer from visual stress may have otherwise normal vision, but they see text as appearing to move, blur or fall off the page. Some report that trying to read black text on a white background is like staring at a stripy shirt or the lines on escalator steps, which can also cause similar symptoms, particularly if the spacing between lines of text is equal to the text size.
The Symptoms of Visual Stress
Patients with visual stress often report the following types of symptoms:
- Movement of printed text
- Blurring of print
- Letters changing size or shape
- Text swirling or falling off the page
- Patterns like rivers through the text
- Halos of colour surrounding text
- Seeing white dots between words
- Tiring easily when reading
What is Colorimetry and How Does it Help?
Research has shown that specific colours may link to different areas of the brain that are responding to the stress caused by the patterns seen in text. For those patients finding reading challenging we use tinted overlays over text to see if their symptoms are reduced with any specific colour.
From our own clinical experience here at MSTC we know that green colours link strongly with eye movement control problems – particularly focussing and convergence issues – so we always make sure that any visual problems that can be treated by exercises, are considered first.
Often coloured overlays can be found which allows the patient to read more fluently and accurately; sometimes a combination of two colours gives the best effect. The overlays will then be used over a period of time to ensure the effects are significant enough to prescribe specifically tinted spectacles, and that any other causative visual problems have been corrected first.
The Benefits of Tinted Lenses
Overlays are useful tools but are limited to set colours. This means when two colours are combined to find the right colour for an individual, the new colour is inevitably darker. That colour may be very helpful, but a lighter version may be even better. With precision tinted lenses we can specify the exact colour and density of colour that is most effective for our patient
Another advantage is that, while overlays can only be used on a book, tinted spectacles can be used to view a computer screen, read an ebook, and copy from the white board in class. Many users of coloured glasses find they also help when writing. Obviously tinted lenses are coloured, which makes them a little conspicuous and occasionally we find that patients are reluctant to use them for this reason: Luckily the benefits are also available in contact lens form!