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Why A Vision Screening Is Not Enough

How can I tell if my child has vision problems that affect their ability to read and learn?

Learning is 80% or more visual. Reading, writing, spelling, computer work, and seeing the board are all learning tasks that our children are required to perform in order to achieve success at school. These visual tasks and others that will be discussed below are all tasks that require accurate vision, quick visual response times, at near, middle, and far distances.

Experts say that 20% of school children do not possess the visual skill set that allows them to succeed in the varied skills required to excel at school. It is important to remember that this 20% is referencing children with and without glasses or contact lenses because having 2020 vision addresses only one aspect of vision. A child in school will use a wide variety of visual skills that not only affect reading speed and accuracy but also include, reading comprehension and the ability to browse through text quickly.

How Do Children React To Visual Problems
Children will react differently depending on their personality, visual deficiency, and social situation. Common behavior includes:
Homework wars
Staying away from any near visual tasks
Developing their own visual shortcuts which may include tilting their head, squinting or closing one eye, or a whatever tricks they devise to help them gain normal vision.
Have a hard time concentrating
Feel tired or even physically exhausted after school or homework
Perform a superficial job of reading or near task assignments demonstrating a low understanding

Why a School Vision Screening Is just not enough A school vision screening tests the ability to pass the eye chart from 20 feet away. Studies show that 43% of children with vision problems can pass a school vision screening. The reason is that many children have visual issues that are not evident when assessing only distance vision. Examples of children that can pass a vision screening are children who have double vision, binocular vision issues, and children with tracking or visual perceptual problems Early identification of a child’s vision problem is crucial because, if left untreated, some childhood vision problems can cause permanent vision loss and all vision problems will affect school performance and social integration.
Why should every parent and educator be concerned about undiagnosed vision issues?
One of the main causes for concern about undiagnosed vision problems is that when the child struggles with school work such as reading and homework, they are far to often being misdiagnosed as having behavioral or learning problems when in reality all that is holding them back is their vision.

What are some common conditions that can cause difficulties for reading and school work?
Amblyopia. Also commonly called “lazy eye,” this is decreased vision in one or both eyes despite the absence of any eye health problem or damage. When one eye is weaker than the other eye, the brain automatically favors the stronger eye and reduces the usage of the weaker eye. This, in turn, causes the weaker eye to become weaker. Common causes of amblyopia include strabismus (see below) and a significant difference in the refractive errors of the two eyes. Developmental optometrists utilize vision therapy, special software, and prism glasses to correct amblyopia in children and adults.
Strabismus. Also known as crossed eyes, is the misalignment of the eyes, which affects eye positioning and movement. Left untreated, strabismus can cause amblyopia in the misaligned eye, double vision, difficulty reading, difficulty concentrating on near tasks, exhaustion after homework or reading and headaches. Depending on its cause and severity, vision therapy is often the right solution for correcting strabismus. In cases where the strabismus is caused by weak eye muscles, surgery may be required, although in many cases surgery is combined with vision therapy for the most effective treatment.
Convergence insufficiency and excess. This is the inability to keep the eye comfortably aligned for reading and other near tasks. Symptoms of Convergence insufficiency are often confused with behavioral problems such as ADHD or ADD. Symptoms tend to be present after reading or near tasks that require immense effort to get the eyes to work together. Common symptoms include double or blurred vision, short attention spans or difficulty concentrating, covering or closing one eye during reading, headaches, problems with reading comprehension. Eye teaming problems, whereby the eyes are not directed at the same image, affects an estimated 5-10% of children and adults.
According to “A Randomized Clinical Trial of Treatments for Convergence Insufficiency in Children”
After 12 weeks of treatment, 8 (53%) of the 15 patients in the vision therapy/orthoptics group were considered “cured” and 80%, “improved.” In contrast, none of the 11 patients assigned to pencil push-ups and only 1 (8%) of 12 patients in the placebo vision therapy/orthoptics group were “cured” or “improved.”
Focusing problems. Our eyes are like a camera, automatically adjusting focus from near, to far, to mid-distance viewing. Children with focusing problems (also called accommodation problems) may have trouble changing focus from distance to near and back again (accommodative infacility) or have problems maintaining adequate focus for reading (accommodative insufficiency) or may be slower at adjusting. Imagine a child with focusing problems looking back and forth from the board to their book, every time losing their place as their vision tries to catch up. Children with focusing or accommodative problems will attempt to get out of reading, have trouble focusing, show signs of exhaustion after reading, and demonstrate signs of both physical and visual discomfort when reading. These problems often can be successfully treated with vision therapy.
Tracking. Eye tracking skills are essential for reading, allowing the eye to smoothly transition from word to word and line to line. In other areas of life, such as sports, tracking plays a vital role in hand-eye coordination. Children with poor tracking will have slower reading, lose their place often, and