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Vision Therapy: What It Is and How, And When To Refer Patients - Featured August 30, 2010

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Vision Therapy – What It Is & How, And When To Refer Patients

By: Lesley Barker, MAT
© 2010

Vision therapy is a series of guided activities to help patients gain and improve control of their eye muscles, learn to team their eyes together more efficiently, cope with visual-spatial demands, as well as correctly to interpret and respond to the visual information received through the eyes with appropriate, accurate movement. Vision therapists work under the supervision of developmental optometrists and often are trained in-house by the doctors. While no mandatory certification exists at this time for vision therapists, there are efforts to standardize and monitor the field under the leadership of the College of Optometrists in Vision Development (COVD), a professional association of developmental optometrists. This association maintains a searchable data base of developmental optometrists on their website http://www.covd.org. When you are seeking a vision therapy provider in your area to refer patients, input the zip code in the search engine on the COVD website. Then, do the networking to get to know the doctors, their philosophy, and to observe their therapy staff at work. This will give you the information you need to determine which of the vision therapy providers in your area best align with your treatment goals and philosophy.

According to the Vision Council of America and the American Optometric Association, one in four school-age children have learning-related vision problems. These problems are missed over 11% of the time in routine vision screenings such as the ones administered by school nurses. Yet, these issues can impair a child’s ability to thrive academically and, they can often be remedied with appropriate treatment and vision therapy. But, patients whose developmental issues may have a delayed or deficient visual component at the root probably will not realize it especially if they pass the vision screening and their eye doctor concludes that they have healthy eyes and 20-20 vision. Other therapy providers who treat these patients should be aware that visual skills cluster into five large skill groups each of which can be assisted to function at an appropriate developmental level through vision therapy.

Eye movements. Eye movements are technically called ocular motilities and include both saccadic eye movements and pursuits. These are voluntary movements of the eye muscles in response to visual targets. You make a saccadic eye movement when you quickly and accurately shift from pointing your eyes at one stationary visual target like a word or a puppet to another stationary visual target. You are using pursuits when your eyes follow a moving target without deviating from it.

Patients who have been diagnosed with Attention Deficit Hyperactivity Disorder may also have a deficit of saccadic eye movements. Instead of being unable to control their attention, the problem may really be that they have not learned to control the muscles that move their eyes. If a patient cannot hold a visual fixation, they will have difficulty locating things, writing, reading, hitting or kicking a ball, and with social skills that depend on making eye contact with another person.

Reading, in particular, depends on accurate saccadic eye movements. A saccadic eye movement is the short hop that your eyes make when they go from one word to the next or from one line to the next. Children with deficits in their saccadic eye movements often lose their place when they are reading. They may skip little words or whole lines of text. They may report that the words on the page move or wiggle.

A routine eye exam by a developmental optometrist will catch an ocular motility deficit. There is a normed test of a child’s eye movements, the Developmental Eye Movement Test (DEM), This test takes about 3 minutes to administer, another five minutes to score, and is appropriate for patients aged 6-13 years of age.

The vision therapy protocol to address a deficit of ocular motilities includes monocular exercises done with a patch. They include charts, games like “Marble Trap”, hitting a Marsden Ball, and doing eye stretches and jumps with “Wolff Wands.” Paper and pencil activities like “Michigan Tracking” are often sent home to be facilitated by the patient’s parents between weekly in-office sessions of vision therapy. The amount of time that it takes to remediate an ocular motilities diagnosis vary widely with the patient’s other visual issues, their age, motivation, and cooperation.

Eye Teaming. Sophisticated binocular skills are also needed for success in learning to read. Both eyes must point accurately to the same visual target at the same moment in time in order for the patient to obtain a clear image that has depth and is single. Developmental optometrists often specialize in treating problems with binocularity.

There are three main skills involved in good binocular function. When reading, the eyes must coordinate at a near-point target. This is called convergence. Teaming to focus on an object in the distance, like a baseball being released from the hand of the pitcher when you are the batter, is called divergence. Switching from a near target, like the worksheet in front of the student, to a far target, like a poster on the wall – going back and forth from near to far requires both eye teaming and a change in focus: this is called accommodation. When a child has problems with binocular vision, it can make school work in general, very tedious.

Another set of patients who have difficulty teaming their eyes are patients who have amblyopia. Amblyopia, commonly called “lazy eye” is when the acuity of the two eyes differ from each other by two or more lines on the Snellen Eye Chart. Children with amblyopia are usually very aware of which is their better eye and hate the vision therapist’s insistence that they patch the stronger eye to force the weaker eye to work. Once the eyes have similar skills – either because of the benefit of wearing the patch and the activities done in vision therapy, or because of the use of corrective lenses in a pair of glasses, these patients can be trained to team their eyes to obtain a three-dimensional image with depth and float.

Children who have a convergence insufficiency may complain that words on the page they are reading appear to be blurry or doubled. The effort to get them to be in focus may be so difficult that they have frequent headaches. They may not be able to sustain their focus long enough to read a whole passage or chapter. Teachers or parents may accuse a child with a convergence insufficiency as being too slow or uncooperative. These children may even say that their stomachs hurt when they read. Reading will be stressful, painstaking, and anything but enjoyable.

Children who have a convergence excess may also report headaches and have difficulty when reading. They do not see a double image or a blur. Instead they have trouble relaxing their focus when they look away from the page.

Children with insufficient accommodative skills will have difficulty copying or changing their focus from near to far. Adults who cannot accommodate wear bifocals. Often children can be assisted to accommodate normally with the help of lenses used systematically in a program of optometric vision therapy.

There is a variety of activities and instruments used by optometrists and optometric vision therapists to remediate problems with binocular vision. First, any refractive error is corrected when the eye doctor prescribes glasses. Then the function of each eye alone is addressed using the same kinds of activities described for treating ocular motility deficits. Heavy use is made of the Brock String, prisms, vectograms, and red/green lenses. Flipper lenses that demand a patient to shift their focus between near and far quickly improve the patient’s accommodative skills. It takes an average of 12 in-office visits to address a convergence insufficiency in children and teens. However, because many patients present with more than one visual deficit or delay, the amount of time predicted for vision therapy to last varies widely from patient to patient.

Laterality and Directionality is a perceptual visual-spatial skill that involves knowing left and right on yourself, on others, and being able to project directions away from you into space. Many people think in terms of dominance – you write with the dominant hand, throw or bat with the dominant arm, kick with the dominant foot. Developing dominance is not as much the issue as being able to cross the midline of your brain. Children with delays in the skills of laterality and directionality may make reversals when reading and writing. They may not be able to distinguish b’s, d’s, p’s, and q’s from each other. They may not reliably progress from left to right and from top to bottom on a page. They may mirror write. This skill impacts a person’s ability to navigate using a map or when driving. It is important for math tasks involving shapes, using graphs, geography map skills, and handwriting, spelling, and reading numbers with more than one digit correctly. It is essential for success in sports and to be able to succeed at certain exercises that require coordinating the left and right sides of the body.

Optometric vision therapists use a lot of gross motor and kinesthetic activities to remediate problems with laterality and directionality. In fact, many of the gross motor activities vision therapists use to address delays in laterality and directionality have been borrowed from occupational and physical therapy activities.

Visual Perceptual Skills are a cluster of visual skills that depend more on how visual information is interpreted by a patient than on whether the eyes are moving and teaming well. Visual Discrimination is the skill that allows a person to determine if two images are the same or different. It is an essential skill for recognizing the alphabet, telling similar words apart, doing geometry, and geography. Visual Memory is the skill that allows a person to recreate a visual image, letter, number, map, or page in a book in his mind. Visual Form Constancy helps a person know whether a teacup is still a teacup when you turn it upside down; if New York still north of Florida when you view a map that is drawn correctly, but so that north is at the bottom of the page; if a “b” still a “b” if the circular part is to the left of the stick; if a triangle is still a triangle when the hypotenuse is at the bottom; and what makes a triangle different from a pentagon. Visual Sequential Memory is the ability to remember the order in which visual images are displayed. This is valuable for solving logic problems, spelling, and early reading comprehension. Visual Figure Ground is the skill one uses to solve “hidden pictures.” It is related to the ability to identify important details and ignore the visual clutter that obscures what you need to observe. It is essential for success in geometry and geography and connects to the ability to use main ideas or details in reading and writing. It is also the skill that allows a child to space his words and letters correctly, when writing. Visual Closure is a skill that allows a person to predict what a shape or letter will be before it is completely drawn, or exposed. Given three points that mark corners of a rectangle, can the child locate where the fourth point will be? This skill is essential for letter recognition, sight word recognition, handwriting, geometry, and the ability to build models and diagrams.

Developmental delays in these Visual Perceptual Skills will affect a child’s scores on tests like the WISC, the IQ test, and many of the various metrics used to diagnose both giftedness and learning disabilities. Behavioral optometrists use a variety of tools to evaluate a child’s visual perceptual skills. Delays in any of these skills are often addressed using games, parquetry blocks, tangrams, and other activities during optometric vision therapy sessions. In vision therapy we expose patients to these skills in a systematic way so that over time students can gain competence and improve performance.

The skill of Visual-Motor Integration relies on applying visual information (that has been correctly perceived and evaluated) to motion. Children with visual-motor integration delays will have poor drawing skills, poor handwriting, difficulty with fine motor skills like stringing beads, or moving game board pieces without knocking others over. Visual-Motor Integration improves with experience, patience, and practice. Many children are helped by using a pencil grip when writing. Behavioral optometrists use normed tests to evaluate a child’s visual motor integration abilities and then recommend a series of activities to be used in therapy to improve it. Good activities to build your child’s visual-motor integration skills include: geo boards, stringing small beads, “Perfection” game, LEGOs, origami, and needlework. Visual-Auditory Integration is a similar skill where the two systems, sight and hearing, coordinate interpreting and responding to the delivery of sensory data.

Vision Therapy & Patients with Autism Spectrum Disorders. Vision therapy may be especially indicated for patients on the Autism Spectrum. Optometrist and author, Dr. Melvin Kaplan recommends the use of therapeutic yoked prism glasses to shift the gaze of patients with Autism up, for example. In my experience, the use of yoked prisms in therapy can be very beneficial for special needs patients who have difficulty transitioning between tasks or who resist new concepts or instruction sets. Yoked prism glasses can also assist some patients to adopt a more typical walking gait. In addition, patients with Autism Spectrum Disorders often have a very difficult time shifting from their central focusing system to their peripheral system. Vision therapy can help these patients to become aware of and comfortable handling visual information from both of these systems. When this happens, some of the “stimming” behavior such as arm flapping, for example may be reduced.

How can you locate an experienced behavioral optometrist in your area? Use the internet to find a developmental optometrist who does vision therapy. The Optometric Extension Program Foundation (http://www.oepf.org) is a nonprofit organization that promotes visual health and has a national referral data base for behavioral optometrists. COVD has an extensive introduction to vision therapy on their website. It is well worth exploring. Another website which is by and for parents is http://www.pavevision.org. These websites are filled with information for parents and educators about vision, visual perception, and more. A no-cost vision screening for babies between six and twelve months is available through the InfantSEE program, an outreach of the American Optometric Association.

As therapists we all work with patients who have multiple issues. One important goal should be to develop an integrated approach that sequences the various indicated therapies. Many of my patients’ parents juggle the costs of multiple therapeutic interventions feeling guilty about having to stop one therapy to start another. Hopefully the more we learn about each other’s practices, the more we can serve our patients and their parents with meaningful information and coordinated advice.

This Month's Featured Author: Lesley Barker, MAT

We thank Lesley Barker, MAT, for providing us with this article for our newsletter.

From 2002 through March 2010, Lesley Barker worked as an optometric vision therapist with the Center for Vision & Learning. This is the pediatric and binocular vision care office affiliated with Webster Eye Care in St. Louis, Missouri. Gail Doell O.D. and Cheryl Davidson O.D. are the partners. Both are developmental optometrists who specialize in binocular vision care and in children’s vision. They trained and supervised Lesley’s work with their patients at the vision therapy clinic. She is a vision therapist member of the College of Optometrists in Vision Development (COVD). She brought more than 25 years of teaching to the vision therapy clinic. This is why, when she realized how lacking is the communication between education and optometry that Lesley wrote the Eye Can Too! Read series of three e-books for K-8th grade students in the home-school context. The books are available from the website: Eye Can Too! Read, the BLOG:, and on the Eye Can Too! Read page on Face Book.

Tags: Article Newsletter 27 August 2010 Vision Therapy Autism ADHD Special Education