How specially tinted glasses helped a girl to fix her reading problems
I sometimes have the good fortune of seeing some very special patients in my Behavioural Optometry practice. This was the case of a 15 years old girl that I reviewed recently. Two years ago, she and her mum arrived at my practice referred by her optometrist who suspected a problem following a “normal” sight test because she was struggling to focus her eyes on text and keeping both working together. This problem could not be corrected by regular spectacles.
Traditional Optometry is concerned purely with spectacles to make distance and reading charts look clearer, Behavioural Optometry on the other hand is a special discipline within Optometry that is dedicated to investigating and understanding exactly how the eyes and visual system works, especially when learning information through the eyes. This kind of assessment will probe and examine the working and the limits of the visual system to find areas that are not performing as well as expected.
After conducting the extensive battery of tests I found out she had many difficulties with her physical visual skills, including eye movements (tracking), binocular vision (using both eyes together) and focusing. She had difficulties with processing and making sense of visual information, including low working memory, visual spatial awareness and using the mind to imagine what she is reading. These problems also indicated symptoms of Visual Stress, an underlying neurological disorder that makes it harder for people to process words when reading, words are sometimes distorted or move on the page. The result of these issues, both physical and processing meant that she first struggled to control her eyes in order to see clearly when reading and then had difficulties in understanding the words.
Vision Therapy is the typical way of treating these kind of difficulties; by following a regime of eye exercises, visual skills can be improved and strengthened. Also, the symptoms of Visual Stress can be neutralised in some poor readers by using specially tinted lenses. In the case of this young girl, she showed a 20% increase in reading speed with tinted lenses. She was prescribed these along with exercises to undertake.
Unfortunately, she was recently in a car accident and subsequently started noticing more difficulties when she reads, this prompted her mother to bring her back to me for another assessment to investigate her visual skills once again. On examining her again I found that specially tinted lenses still improved her reading speed. But now I had an opportunity to investigate exactly how the lenses were making such a huge impact. I used the Okimo system based on eye tracking in order to record and demonstrate the difference (and improvement) in eye movements and reading speed with her new tinted lenses.
After performing a reading test, with and without glasses I was astounded. The difference was amazing: without the lenses she has extremely poor control of her eye movements therefore giving her significantly low levels of reading comprehension and difficulties with learning. As soon as she wore the glasses her eye movements improved immediately. She moved her eyes about half as many times and more accurately as can be noticed in the images below.
The other valuable test is the Pursuit Test (see below). This is an accurate way of monitoring her eye movement control. The system monitors the ability and accuracy of the eyes to follow a target moving across the screen. The plots below show how closely her eyes kept their attention and movement with the target. The top plot (without tinted lenses) showed very erratic and uncontrolled eye movements. The lower plots shows that she can follow the target much more accurately with the specially tinted lenses. As you can see she really struggled with her eye movements without the tinted lenses.
Without the lenses she had to move her eyes about twice as much and with poor control, compared to wearing them, which means her eyes and brain would tire twice as quickly and take in significantly less information. It’s no surprise that she was struggling to read and learn!
There is still a lot of work to be done, but as a Behavioural Optometrist I feel very satisfied being able to prove and demonstrate objectively the presence of a significant and manifest visual processing problem that can be improved using the methods and techniques at our disposal.
On seeing the results of this test her mother could instantly see and finally understand the underlying mechanism of the problems her daughter is experiencing whenever she tries to learn. In her own words: “it was very helpful and clear to understand what the issues were and how the glasses were helping.” Also my young patient felt relieved, since she could see for the first time how far away from normal her results were and therefore why she needed the glasses.
This kind of information is a new and powerful way to allow her to take control of the difficulties in her visual skills, and to understand and overcome them.