When you and your child get your eyes tested, you’re likely just wondering if you need glasses or not to help you see better. While correcting your vision for blur with glasses is an effective management, spectacles mainly correct refractive error (myopia, hyperopia and astigmatism). The eyes are a part of a complex visual system and there are, in fact, a number of other vision problems that can present that cannot be corrected with spectacles alone – Glasses are simply the start!
What are other vision problems that can present that are not a refractive error (myopia, hyperopia, astigmatism)?
Amblyopia (lazy eye)
Amblyopia is the term used to describe one eye (sometimes both) with reduced vision, with no pathological cause, despite proper correction of refractive error with glasses. The term ‘lazy eye’ arises because the brain will always favour the eye with better vision and starts neglecting the weaker eye, hence the eye with reduced vision becomes ‘lazy’. If detected early (in childhood), amblyopia can be corrected and/or improved but if it is left untreated, lazy eye becomes a permanent vision disorder. Amblyopia is the leading cause of monocular vision loss in adults above the age of 20.
Convergence and accommodative insufficiency
Convergence refers to the mechanical action of the eyes and their inability to smoothly and evenly turn inwards. Whilst accommodation refers to the eyes’ ability to voluntarily focus and make things clear. Convergence and accommodative insufficiency is a common but overlooked vision condition where the eyes struggle to work together to focus up close. When left untreated, these conditions can cause symptoms such as eye strain, blurred near vision, double vision, frontal headaches and difficulty concentrating on close work. These conditions are usually detected through clinical assessment as they are subtle and only appear in specific but common circumstances. E.g. reading for an extended period of time.
Source: Brighter Outlook Vision
Eye turns (inwards and outwards)
Eye turns are often caused by weak eye muscles. When one eye muscle is not functioning at its best, it causes the eyes to drift as the muscle struggles to activate and pull the eyes to the right position of gaze. This can present as one or both eyes turning out or inwards. Not only does this affect you cosmetically, often resulting in reduced confidence and self-esteem, it can cause visual symptoms like poor depth perception and double vision.
These conditions often present in early childhood, but due to their subtle nature, many children do not recognise that these changes are happening to them as they are unaware that what they are experiencing is not ‘normal vision’. In their shoes, this is their normal. With routine eye testing, these eye conditions can be detected early and hence, managed early. If left unmanaged, they can follow us into adulthood, causing an array of different binocular issues and affecting our overall quality of life.
How do we treat these eye conditions if it is not corrected with spectacles?
Have you ever heard of vision/eye therapy? We’ve all heard of seeking therapy for the mind, but what about for your eyes? Think of it as tutoring but for your eyes or going to the eye gym to do eye exercises.
An extensive amount of research and clinical trials have shown that vision therapy is an effective, safe and non-invasive way to improve function between the eyes in children and adolescents and can improve binocular vision issues. Successful vision therapy relies on consistency and the correct and appropriate eye exercises for the vision problem.
Amblyopia (lazy eye) eye exercises
Vision therapy works through patching and other techniques by forcing the brain to utilise the weaker eye. Research has shown that vision therapy has a success rate of 70-90% in children aged 3-7 years old, with clinically diagnosed amblyopia. As the brain starts to improve its signalling and strengthens the weaker eye, the two eyes eventually equalise and binocular function subsequently improves too.
Convergence and accommodative insufficiency eye exercises
Both of these conditions cannot be treated solely by glasses alone, hence why vision therapy is considered. By training the two eyes with tailored exercises for them to function much more smoothly, equally and effectively.
Eye turns (inwards and outwards) eye exercises
Some types of eye turns can be treated with eye muscle therapy. Vision therapy works to strengthen the deviated eye, improve binocular function and teach the brain to fuse two images together.
Like any muscle of the body, if the weakness is mild to moderate, it can be strengthened with the correct and appropriate tailored eye exercises for the specific eye dysfunction. In severe cases, surgery might be the only option to straighten the eyes.
How does it all work?
The concept of vision therapy can be very foreign to some. One of the reasons vision therapy works well for children and adolescents is due to something called neural plasticity.
Neural plasticity is defined as the brain’s ability to adapt, rewire and form new neural connections in response to changes in its environment.
In children and adolescents, the brain is highly flexible, meaning there is a higher chance of successfully training the brain to adjust its signals to the eye muscles and overtime, improve overall eye function.
As a person ages, neural plasticity declines and thus the success rate of vision therapy also declines, prompting the importance of early detection and treatment of eye muscle conditions.
So remember – Early detection. Early management. Early success!
