Visual acuity, or being able to see 20/20, is not the only important visual skill. To properly function in today’s world, and to learn in the classroom, you need a host of other skills, known as binocular vision skills or oculomotor skills. These relate to the way the eyes move, track objects or text. Binocular vision includes, for example, the ability of both eyes to work together as a team or to be able to move together to focus when doing near work (convergence) or to move apart to focus in the distance (divergence). If you have a deficit in one of these skills, you might not be able to perform optimally in today’s visual word.
Many people have one of the following treatable binocular vision disorders, which too often go undiagnosed:
Accommodative disorders
The inability of the eyes to focus. The eyes must be able to sustain focus for long periods of time when doing near work. Also, the eyes must be able to quickly and accurately change focus from distant to near objects.
Convergence disorders
The inability to use both eyes as a team when looking at something up close. When looking at near objects, both eyes should turn inwards and maintain single vision.
Divergence disorders
The inability to use both eyes as a team when looking at something in the distance. When looking at far away objects, both eyes should turn outwards and maintain single vision.
Oculomotor disorders
The inability to quickly and accurately move our eyes. These are sensory motor skills that allow us to move our eyes so that we can fixate on objects (fixation), move our eyes smoothly from point to point as in reading (saccades) and to track a moving object (pursuits).
In fact, children with the above disorders are often placed in individual learning plans at school because they are not performing well. For example, a recent study found that over 70% of kids with a diagnosis of dyslexia had one or move binocular or oculomotor deficits. Another recent study published in January 2018 in the Journal of Optometry, titled “Efficacy of vision therapy in children with learning disability and associated binocular vision anomalies”, looked at a population of children with specific learning disorders. The researchers found that 62.8% had binocular vision abnormalities and those treated with vision therapy showed significant improvement in binocular vision parameters.
The tragedy is that these kids are often told that their vision is perfect because the only test that was done was the one for visual acuity. Convergence, divergence, eye movement and tracking was not tested. As a result, these kids fall through the cracks and don’t get the help that they need, unless they stumble into are office like ours with a developmental optometrist that tests and treats binocular vision disorders.