Glasses, Patching And Surgery Are Not Enough
It is well known that glasses, occlusion and atropine treatment are considered standard treatment for strabismus and amblyopia in children. Surgery can be successful in treating congenital turns and sometimes necessary for cosmetic straightening.
However such treatment fails to address two important aspects.
- Glasses, patching, and surgery may improve visual acuity (what you can read on the letter chart) and the eyes may appear straight. BUT it does not address how well the two eyes can work together as a team. Hence often after patching is stopped, vision is not maintained. Or after surgery, although the eyes look straight, the worse eye is still “switched-off” and the eye turn can reappear after surgery.
- The brain directs and controls the eyes, as well as process visual information. For example, in amblyopia the brain needs to be re-taught to stop suppressing the weaker/turned eye and begin to accept visual input from it, to allow functional vision
How Is Strabismus And Amblyopia Therapy Different?
Strabismus and Amblyopia therapy corrects the cause of the brain’s inability to align and use both eyes together. During therapy, the patient’s brain is trained to stop suppressing the lazy eye and the visual pathways from brain to eyes are improved so the patient can keep both eyes aligned. Finally the brain is taught to fuse the images coming in from both eyes for normal binocular (“two-eyed”) vision. As a result we aim to make it more comfortable for the brain to use both eyes together rather than suppressing one eye.
The gains achieved in vision therapy are permanent. This is because once the child’s brain learns binocularity, or how to fuse the images from both eyes, the child’s visual system is restored close to normal. Binocular fusion is the glue which permanently holds the visual system in place, simply because it’s easier to see correctly than to have each eye fighting each other to see separately. Binocular fusion keeps the eyes from drifting out of alignment, and because there is no longer a need for the lazy eye to suppress, its sharpness of vision is not lost over time.
Strabismus And Amblyopia Therapy Can Be Done At Any Age
Some parents are told that a lazy eye can only be corrected when the child is very young, usually up to age six, the time when a child’s visual system is still naturally “moldable.” Some doctors feel that if treatment is not undertaken during this “critical stage” of development, the amblyopia becomes fixed and untreatable.
New research has disproven this completely. Strabismus and amblyopia can be treated at any age. The reason is called “neuroplasticity”. It simply means our brains can learn new ways of processing as long as we are alive.
Many individuals that have been told “it’s too late” to treat their visual problem, such as amblyopia and strabismus, have actually experienced dramatic improvement following vision therapy. Susan Barry, a neuroscientist and author of the book “Fixing my Gaze” is the prefect example. She experienced 3D vision for the first time following vision therapy at the age of 48!
What Happens If Strabismus And Amblyopia Is Not Treated?
It is important for children to develop equal vision in both eyes in order for them to function normally. Good sight and two-eyed vision are vital for children to succeed in school, sports, or any other activity that requires clear vision, good hand-eye coordination, and strong depth perception. When children with untreated amblyopia grow to be adults, their choice of career may be limited and, if they are unlucky enough to lose vision in their one good eye, they could be visually impaired or legally blind for life.
What Is The Scientific Research Supporting Vision Therapy?
- There is evidence to suggest up to 75% success rate with vision therapy for strabismus.
- This can increase to 87% when the conditions are optimal such as in private practice optometric clinic with one-on-one individualised care.
- Improved eye teaming following vision therapy lead to improved academic behaviour, reading and school work.
Vision Therapy: Not Just Eye Exercises.
Contrary to common belief, vision therapy is not used to strengthen eye muscles, but to improve the coordination and efficient functioning and processing of the visual system. It is a highly effective, non-surgical treatment for many visual problems such as strabismus, amblyopia, convergence, focussing, tracking, and learning difficulties.
Our visual system uses our eyesight, visual pathway, and brain all together to direct our actions; such as reading and writing. Therefore lacking necessary visual skills or information processing will compromise our ability to perform these actions.
Vision therapy provides the necessary experience to develop these visual skills and process the visual information the brain receives from eye eyes correctly. As a result, a person becomes able to use their visual system efficiently; not just in vision therapy activities, but in their everyday lives. This is achieved by a customised vision therapy program.
Orthoptics is another term often used in conjunction with vision therapy. Orthoptics is one part of a specific vision therapy program directed at improving binocular alignment and visual acuity in individuals with strabismus and amblyopia.
What Is Involved In Vision Therapy?
Following a comprehensive eye exam, your optometrist may identify a visual problem and prescribe vision therapy as a treatment. Each program of vision therapy is designed and tailored to suit the specific needs of the individual, both in terms of their visual profile and their goals. Diagnostic testing, training procedures and the use of lenses and prisms may be integral components of the successful treatment of a vision problem.
The duration of a course of vision therapy will vary depending on the nature and severity of the problem being treated and the specific needs of the individual. Most programs last 6-12 months but more complex issues can take longer to treat.
The patient will meet with the vision therapist once a week for 45 min for the duration of the program and will be prescribed activities to be practised at home for 20 min per day.
Success of the therapy program depends not only on the motivation of the individual and parents involved, but also their compliance with prescribed home activities.
Outcomes of Vision Therapy
When your visual system is able to align, track, focus, and process what it sees the right way, a whole new experience is discovered. You can expect to emerge from the vision therapy program which a much improved vision from that you started with. You may find (but not limited to):
Improved reading level and speed
Improved learning ability
Elimination of symptoms such as sore eyes and headaches
Ability to control an eye turn
Improved focussing and ability to change focus from near to far
Improved distance judgement and 3D vision