An Occupational Therapist Treats Convergence Insufficiency

An OT treats CI

The process the author uses to treat convergence insufficiency has proven in his clinic to be very efficient, effective and repeatable. Symptoms are generally resolved in 8-10 visits for neuro-typical children and adolescences. This treatment process does not include assessment of primitive reflexes though many of the activities (not by design) may help to integrate these retained reflexes. Treatment sessions are twice a week for one hour. Home programs consist of a brock string performed 3-4 minutes in the morning and afternoon. The patient returns for their annual eye exam one year later and remain symptom free.

The Referral

Most of the referrals are made by Dr. Mark Obenchain OD, a binocular vision/peds specialist. He is a graduate of Indiana University where he completed a residency in binocular vision and pediatrics. He accepts all insurances and Medicaid.  Our patients cover a board spectrum of demographics with approximately 2/3rds being neuro-typical and the remaining 1/3rd having an additional diagnosis such as ADHD, Autism, or other developmental delay. A complete pediatric eye exam with cycloplegic dilation is performed on every child under the age 18 regardless of complaints.

The doctor diagnoses CI when:

The OT Evaluation

The occupational therapy evaluation begins with medical history, medication history and a discussion of academic performance and hobbies.

The following testing is performed:

  • extra ocular movements
  • tracking
  • stereopsis
  • near point of accommodation
  • near point of convergence
  • Developmental Eye Movement Test
  • Beery VMI, Visual Perception and Motor Tests
  • Observations are made during proactive and rotator 3 activities on Sanet Vision Integrator for eye-hand coordination, posture and balance. This performed while patient stands on balance board.

The author does not assess visual perception at this time as the patient has been diagnosed with a near vision problem which could taint the results of this test. An OT evaluation is also an untimed code making the 30-45 minute test not efficient to perform at this time. If visual perceptual problems exist after meeting all CI related goals, then visual perception is assessed and treated.

The Goals

The therapy goals are specific and measurable as well as being tied to function.

  1. LTG–Pt to demonstrate age appropriate visual skills
    1. STG–Pt to demonstrate near point convergence< 6 cm on 5 trials
    2. STG–Pt to fuse 15 BO loose prism to demonstrate improved fusion skills for improved reading and close  tolerance.
    3. STG–Pt to complete 20/30 Rock card with 2.00 flipper in 60-90 seconds to demonstrate age appropriate accommodation skills to improve read and close work tolerance.
    4. Complete Developmental Eye Movement test with age appropriate ratio to demonstrate improve ocular motor accuracy for reading tasks.
    5. STG–Pt to demonstrate age appropriate visual motor integration as tested by Beery VMI
  2. LTG–Pt to be (I) in use brock string to support in clinic treatment.

The Treatment Protocol

The below protocol has been effective and repeatable with most neuro-typical children ages 6 and up. The author has modified activities for children that have difficulties with these tasks which lengthens the amount of treatment sessions but are still effective in meeting the above goals.

  1. On the Sanet Vision Integrator
    1.  Proactive, performed monocular using R/B glasses, while standing on balance board, therapist holds head still while patient alternates touching dots with right then left hands regardless of placement of dots.
    2. Rotator 3, monocular, while on balance board. May touch with any hand, verbal cues to recall alphabet as needed.
  2. Convergence activities
    1. Tranaglyph slides with goal of reaching 30 BO and 12 BI.
    2. Loose prism Jump Vergences with “circle X square” tranaglyph for binocular feedback.
  3. Accommodation
    1. Accommodative Rock task, monocular
  4. Saccades 2 task on Sanet Vision Integrator, while on balance board, monocular with R/B glasses, head held still as needed. Goal is achieve 100% accuracy .5 interval with words.
  5. After improving with these tasks, pt may be progressed to aperture arm, often challenged with 1.00 flipper to maintain focus
  6. Visual motor integration tasks, tracing shapes, copying geoboard forms on paper and/or chalkboard/SVI and other visual motor tasks.
  7. HTS Autoslide performed at end of session

CPT code 97530- therapeutic activities, a timed code, is used for all sessions.

The Outcome

Patient are discharged upon reaching all goals as stated above on two consecutive visits. When this has occurred there have been no re-referrals for CI. There is also a resolution to many other symptoms including

  • resolution of headaches
  • improve reading fluency
  • a resolution to letter reversals in most cases
  • improve handwriting
  • improvement is self-esteem

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Autism and Vision

Autism and Sight

There has been several recently published articles on autism with some dysfunctions being found at a higher rate than in the neuro-typical population. One study, published in January 2017, found consistently that children with autism reacted slower to changes in light (pupillary light reflex). The pupillary light reflex was slower when lighting changed and, in darkness, the pupil measured smaller than controls.(1)

A second study, published in 2018, found a higher rate of accommodative problems (17.4% for ASD, vs 4.9% control) for children diagnosed with autism. While there was no substantial difference in the rate of refractive error, this higher rate of accommodative problems makes a complete eye exam with assessment of near vision acuity more important.(2)

A review of evidence found several contradictory studies concerning the prevalence of eye movement defects associated with autism, though most agree that saccades inaccuracy as well as difficulties in tracking are common in ASD. These movement problems, coupled with other fine and gross motor deficits found in autism suggests a cerebellar problem.(3)

Autism and Vision

Difficulties with the integration of visual information is found in several studies. All of these studies point to a lack of integration between the parvocellular and magnocellular tract and reduced communication between these tracts.(3)

Studies found differences in VEPs (visually evoked potentials) studies in the activity of the magnocellular tract compared to neuro typical children. The difference was, most notably, a slower recovery period for the magnocellular tract and therefore, decreased integration of the information. Functionally, this may help explain the visual spatial problems frequently seen in ASD diagnosed children. (4, 5)

Lateral gazing’ behavior was also found in some children with ASD as they attempted to use peripheral vision to reduced central visual pathway input. (3) This behavior is also suggestive of magnocellular tract deficits.

Integration Deficits

A common thread through many of these studies is a decreased integration of visual information and motor pathways and the cerebellum. (6) This lack of integration could help explain the ocular motor and saccade problems, as well as increased incidence of gait problems and toe walking (7,8) and visual motor integration problems found in children with ASD. A study also showed that people with ASD do not make good use of visual information to correct posture (9). Addressing this lack of integration could be helpful making functional progress with children on the spectrum.

Summary

A complete binocular vision exam with cycloplegic dilation is very important for every child with autism (and neuro typical children too) given the potential for a higher rate of accommodative and ocular motor problems and fine motor, reading and handwriting problems.

Given the evidence of integration problems, activities for children with ASD should be “top down” type activities that require the integration of movement and vision.

Much of this research is very recent and found some changes from previous research. Many of the studies suggested these differences in results were related to redefining autism with the release of DSM-5 eliminating Aspergers and pervasive developmental disorder and grouping these into the current terminology of autism spectrum disorder. The inclusion of these subjects in studies have helped improve the understanding of vision and autism. Many of the studies also sited small samples as potential limitations.

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(1)Anketell, P. M., Saunders, K. J., Gallagher, S. M., Bailey, C., & Little, J. A. (2018, March). Accommodative Function in Individuals with Autism Spectrum Disorder. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/29424829

(2)DiCriscio, A. S., & Troiani, V. (2017, July 25). Pupil adaptation corresponds to quantitative measures of autism traits in children. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/28743966

(3)Bakroon, A., & Lakshminarayanan, V. (2016, July). Visual function in autism spectrum disorders: a critical review. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/27161596

(4)Jackson, B. L., Blackwood, E. M., Blum, J., Carruthers, S. P., Nemorin, S., Pryor, B. A., . . . Crewther, D. P. (2013, June 18). Magno- and Parvocellular Contrast Responses in Varying Degrees of Autistic Trait. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/23824955

(5)Sutherland, A., & Crewther, D. P. (2010, July). Magnocellular visual evoked potential delay with high autism spectrum quotient yields a neural mechanism for altered perception. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/20513659

(6)Miller, M., Chukoskie, L., Zinni, M., Townsend, J., & Trauner, D. (2014, August 01). Dyspraxia, motor function and visual-motor integration in autism. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/24742861

(7)Accardo, P. J., & Barrow, W. (2015, April). Toe walking in autism: further observations. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/24563477

(8)Kindregan, D., Gallagher, L., & Gormley, J. (n.d.). Gait deviations in children with autism spectrum disorders: a review. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/25922766

(9)Morris, S. L., Foster, C. J., Parsons, R., Falkmer, M., Falkmer, T., & Rosalie, S. M. (2015, October 29). Differences in the use of vision and proprioception for postural control in autism spectrum disorder. Retrieved March 05, 2018, from https://www.ncbi.nlm.nih.gov/pubmed/26314635

The Hart Chart

Accommodation

Accommodation is one of the mechanisms that allow us to see up close. Accommodation is the focusing of the lenses in each eye. This action, combined with the convergence, allows for us to see clearly up close. 

Accommodation is the result of the contraction of the ciliary bodies in the eye which allow for the lens to get thicker thereby focusing the image better in the fovea. This action also includes the constriction of the pupil which more precisely focuses the light on fovea making the image sharper. Here is video of this in action

 

“Its blurry up close”

When accommodation does not work, one may see blurry up close, get headaches or rub the eyes due to eye strain. The ciliary muscles attempting to make the image clear, causes this discomfort discomfort. Accommodation can be exercised to strengthen it to improve near vision. This is generally performed in conjunction with convergence exercises to improve near vision  when one treats convergence insufficiency.

The Hart Chart

A simple way to improve convergence is using a Hart chart. With this activity, a grid of letters is placed at distance and one is held by the patient, near. The patient then reads a line close (or letter) then a line at distance. This is done with one eye occluded so the accommodative action is exercised as the eye focuses near then far. In my clinic, this performed while standing on balance board to further challenge the patient. This simple activity is quite effective at strengthening accommodation. A Hart chart can be purchased from Bernell, found on the internet and is included on the Vision Rehabilitation for Pediatrics Course Companion flash drive. Heres a video.

The Hart chart is one way accommodation can be strengthened. In optometric vision therapy, lenses can be used to strengthen accommodation using an activity called Accommodative Rock.

Support your local Optometrist

A complete binocular vision assessment should be conducted before performing these tasks to make sure that are appropriate. Only an ophthalmologist or optometrist can accurately diagnose an accommodative problem.

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Fine motor skills and vision

Does binocular vision affect fine motor ability?

Occupational therapy has been treating fine motor problems since the beginning of the profession. From tying shoes to buttoning to handwriting, when children or adults have difficulty with this, occupational therapy is referred.

Binocular vision?

A small study (1) looked at the fine motor skills of children with reading difficulties and found those with fine motor problems also had binocular vision problems, specifically accommodative problems.  While a small study (19 children), this suggests that vision is playing a role in fine motor coordination.

Another study (2) found that children that were poor readers showed a higher occurrence of binocular vision difficulties and suggested a need for the assessment of these skills in problem readers.

Research also indicates the importance binocular vision and motion perception to development of the motor skills(3) as young a 2 years old.

OT and binocular vision

As therapists, we are seeing children with difficulties that could have a binocular vision component. While a through binocular eye exam should be completed to rule out treatable defects, therapists integrating tracking, saccade and convergence activities could help improve outcomes for their patients. Our background in developmental sequence, kinesiology and assessment of functional ability make therapists the perfect profession to address these deficits. As therapists, we address the motor part of visual motor problems, but basic tracking, eye-hand coordination tasks could help with outcomes by improving the visual aspects of this skill.

The Therapist/OD team

Therapists, both PT and OT, should get the training to feel comfortable integrating these simple tasks into the interventions they already perform. Next, reach out to optometrists in their area. This relationship will be beneficial for both the therapist and optometrist, but mostly, this will help the patient.

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(1)Niechwiej-Szwedo, E., Alramis, F., & Christian, L. W. (2017, October 27). Association between fine motor skills and binocular visual function in children with reading difficulties. Retrieved November 13, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/29096178

(2)Palomo-Alvarez, C., & Puell, M. C. (2010, June). Binocular function in school children with reading difficulties. Retrieved November 13, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/19960202

(3)Thompson, B., McKinlay, C. J., Chakraborty, A., Anstice, N. S., Jacobs, R. J., Paudel, N., . . . CHYLD, T. E. (2017, September 29). Global motion perception is associated with motor function in 2-year-old children. Retrieved November 13, 2017, from https://www.ncbi.nlm.nih.gov/pubmed/28864240

 

 

Equipment for Vision Rehabilitation

“What tools do I need to perform basic vision rehab interventions in my clinic?”

The first thing one needs is information. Understanding and Managing Vision Deficits-A Guide for Occupational Therapists would be a wise investment. Dr. Scheiman’s book explains assessing and treating basic binocular vision defects making the subject approachable for therapists. He also teaches a course by the same name that would be a good start.

Vyne Education also offers a course Vision Rehabilitation for Pediatrics-Seeing the Whole the Picture, taught by this author also introduces basic assessment and treating of eye movement disorders.

The Convergence Insufficiency Treatment Trial Manual’s Chapter 8 explains the in-clinic activities used in the CITT and would also be a worth while read.

You will need an optometrist

This may be the hardest thing to find. While the complete binocular vision assessment is the standard of care, frequently this assessment is neglected. Find the optometrist in your community that consistently performs these assessments and you will most likely find a partner. COVD and NORA doctors may be most receptive to working with a physical or occupational therapist that is training in binocular vision disorders.

The optometrist diagnosis is as important as the diagnosis a therapist would get before starting rehab on a shoulder. While we can perform basic testing on a shoulder, some results would indicate further assessment by the orthopedist. Same rules would apply concerning eye movements except that even poor tracking could be caused by a lack of visual acuity requiring glasses (or more accurate glasses).  Always insist that a child have a current eye exam before working on eye movement or even skills like visual motor integration or visual perception. Performance of these tasks requires best corrected visual acuity.

What about Equipment?

The Worth 4 dot   would be a wise first investment. With models starting at about $20, it it also very cost effective and gives great first clues to a eye movement problem.

Marsden Balls offer an easy to use moving target that requires good fixation to read letters. The handy therapist could probably make one on their own.

The Hart Chart is simple way to strengthen accommodation. Do it on a balance board and add in the challenge of balance.

The brock string is a must and its cousin the barrel card can be used to strengthen convergence.  Have the patient make their own brock string becomes a great fine motor activity too.

The Developmental Eye Movement Test is quick to give assessment that gives good data to reading ability and accuracy.

 

Prism and Lenses

The rules governing the use of prism and lenses vary greatly from state to state with the interpretation of the rules varying. Because of this, the author has chosen not to openly recommend these tools. They would generally require being under the supervision of an optometrist or ophthalmologist for there use and purchase.  They also require training to understand the appropriate therapeutic use of these tools.

Be a therapist!

The near-far axis is generally referred to as the Z-axis. When we turn our midline crossing tasks into the Z axis, we are now working the near far visual system.  Check out a previous post here. Be creative and have fun.

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Convergence Tasks for Therapists

The Z axis

As therapists, we recognize the importance of mid-line crossing to help with primitive reflexes.  Reaching lateral outside of the base of support challenges balance and posture.

But to exercise convergence, the therapist must turn their favorite activity into the “Z axis”. This axis is the near-far axis, (referred to as the Z axis in vision) and challenges the convergence and accommodation system.  Many of our favorite activities can be modified just by turning them, to help strengthen the near vision system.

Simple convergence strengthening activities

Clothespins are great therapy tool, strengthening pinch for writing and other tasks. Having a child reach to a distance to retrieve the clothespin then hanging the clothespin on a near string can can help with convergence and divergence. The proprioceptive input of the hand hanging the clothespin on the string will cue the eyes to converge to a point.

The swing adds vestibular and proprioception to the convergence and divergence in this video.

In my clinic, I also use a cup with a straw that patients then put toothpicks in. This task can be graded by moving the cup closer to the child’s face.  This is task also made more difficult by not allowing the kiddo to touch the straw, removing the proprioceptive input,  forcing the eyes to guide the hand more accurately.

Amazing creative therapists

Cheerios on a Straw

In the task, the patient puts cheerios on a small coffee stirrer. The hand working at the end of the straw does a great job cuing the eyes to converge. Just make sure the straw stays in at mid-line.

Ball in a Tube

In this task, a 4 ft florescent bulb protector ($4 at Home Depot) is cut in half with a ping pong ball put inside. I then placed stickers on top of the tube. The patient has to align the ping pong ball under the the sticker. In standing? Even better. Balancing on a balance board? Even better!!!

As a bonus, the scrap end of the tube become a great “light saber” for popping bubbles to work on tracking and eye hand coordination.

Thanks to therapists that I have met

The weeks I spend traveling are exhausting but the energy of the people I met help me stay motivated. Thank you to all the therapists and teachers and others, that I have met.

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The Binocular Vision Exam

The Child’s Special Visual System

Children’s eyes are amazing. They bring the world to an eager child and facilitate development of many skills.  The visual world influences posture and gait, fine motor development, letter recognition on to reading skills and many other areas.  The importance of good vision cannot be over stated.

The Pediatric vision exam

The vision exam for a child should include assessments not generally not performed on adults. Check out this post first to understand how we see up close. 

  • Cyclopelgic Dilation and Refraction- This allows for the doctor to completely exam the retina of a child for optic nerve problems and other congenital problems that child may have. The cyclopelgic dilation also relaxes the ciliary muscles which control accommodation (focusing of the lens within the eye). This allows the doctor to exam the true refractive error of the eye which can frequently be corrected by the accommodation of the lens.  This should be considered mandatory once a year.
  • Near Point of Convergence – This brief assessment allows for the doctor to assess how how well the eyes are working together when seeing up close.
  • Measured cover test- A cover test reveals the amount of effort needed for the eyes to maintain their position. It also shows subtle eye movement problems like strabismus.
  • Retinoscopy – in this assessment, the doctor can get an objective measurement of refractive error. This eliminates communication problems some children may have and makes for the most accurate solution for a child;s visual acuity.

Better or Worse

General optometrists and opthamologists may or may not perform these tests.  Without them, an important part of the assessment of a child’s vision has been left out. Eye movements can cause delays in gross and fine motor development and decreased reading performance and difficulty in sports, like hitting or catching a baseball.

Look for doctors that advertise being pediatric or binocular vision specialist. Look for doctors that members of the College of Visual Development or the Neuro – Optometric Vision Association.  These are doctors that specialized in the assessment of binocular vision skills.

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Dyslexia and Vision Rehabilitation

Dyslexia and Vision Therapy

Dyslexia is word frequently tossed about when children have problems reading or learning. Commons complaints that lead to the use of the word include letter reversals, poor reading comprehension and decreased reading fluency. These symptoms are also recognized as possible vision related problems cause by poor eye movement accuracy.

Is dyslexia a vision problem or a language problem?

Attempting to define dyslexia can be confusing. The origin of the word is vague: “dys” meaning difficulty with and “lexia”  meaning reading lends itself to broad interpretation.  The best definition for dyslexia, from the International Dyslexia Association says:

“Dyslexia is a specific learning disability that is neurobiological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede growth of vocabulary and background knowledge.”

The research shows that the root cause of dyslexia is phonological processing, or how the brain processes sounds in language. Additionally, the prevalence of dyslexia is estimated to be between 5-20% of the population, according to the National Institute of Health: http://www.ninds.nih.gov/disorders/dyslexia/dyslexia.htm. *

Reading is a complex process involving language, speech, memory and other processes, but all of these processes assume that the collection of the information to be processed is accurate, ie that the eyes work correctly and move accurately. We do know that poor eye movements lead to poor processing skills because the data to be processed was not collected accurately.

Does vision therapy treat dyslexia?

This is also a very interesting question. In our vision rehab practice, we frequently get children referred to us that have common symptoms of dyslexia and visual processing difficulties like reversals and poor reading skills. Following the interventions, the children have reduced symptoms and most have improved reading fluency.

Some of patients do continue to have problems in reading although they show improved eye movements. At this point, we may further assess the patient using a dyslexia screening tool that can identify specific errors related to the processing parts of reading such as the decoding and encoding of words. When results indicate, we refer those children to specialists like our friends at Read-Write Learning Center at  that specialize in the treatment of dyslexia.

 

Does vision therapy treat dyslexia????

NO. Vision therapy cannot treat dyslexia. But it does improve the accuracy of eye movements eliminating many of the symptoms generally associated with dyslexia. With these eye movement problems gone, an accurate assessment of the visual processing skills and reading fluency is now possible, allowing for an accurate diagnosis of a visual processing or other reading and learning problems.

Here is a video case study describing the process.


*Special thanks to Hunter Oswalt, Director of the Read-Write Learning Center for her input on editing this post.

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Visual Processing Disorder

Visual Processing Disorder

Visual Processing disorder is broad term used to describe children that have difficulty with visual tasks. They may have problems with puzzles, mazes, handwriting or reading. The child may be clumsy and have difficulty remembering things like where toys are located. Visual processing problems can be different in each child. Here is a symptom checklist that might help.

Sensory Processing Disorders

Visual processing disorders are part of a larger group of disorders called “sensory processing disorders“. Sensory processing disorders can be linked to any sense (touch or hearing, vision, taste or smell) and are characterized by the brain magnifying or muting sensory information. This magnification or muting of the sensation can appear a child that does not like loud noises, or constantly likes to touch rough surfaces. They may be picky eaters because some foods “feel funny” in their mouths or they only wear their favorite super soft shirt.

These sensory difficulties can cause problems with fine and gross motor development as well as academic performance and cause behavioral issues as well.

Causes of Sensory Processing Disorder

Research continues to identify causes of these disorders but no real conclusions have been found. There are differences in brain structure noted in these children and environmental toxins have been linked to these disorders.

Treating Visual Processing Disorder

Children diagnosed with visual processing disorder should first have complete eye exam including a binocular vision exam. Children with visual processing disorders and other sensory disorders are frequently found to have eye movement and near vision focusing problems that only a binocular vision assessment can uncover. Treatment for the eye movement and near vision focusing problems can frequently reduce the symptoms associated with visual processing disorders.

Following resolution of the eye movement problems, we can ONLY THEN begin successful treatment of visual motor integration and visual perception problems.

Neurological Events and Visual Processing disorders

Recently, I have had several children referred to me recently with “visual processing problems” that also have histories of seizure disorder and concussion. These children also had significant binocular vision problems. Once their binocular vision disorder was correctly diagnosed (both had CI, accommodative dysfunction and saccade dysfunction) and treated, we then able improve visual processing for both of these children.

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How do we see up close?

The Near Vision System

“I can’t see the board” is a common reason children come for their first eye exam. But problems seeing up close are more closely related to academic success than distance vision problems. With more computer use, and frequent changes from looking at the board to a notebook, school can be a workout for the near vision focusing system.

Watering eyes, rubbing eyes, and headaches are early signs of problems with near vision. These soon lead to difficulty reading and falling grades. The child may also show avoidance behaviors when trying to do school work as it is physically painful to see up close. But worst of all, the child may not say anything at all, as they do not know that their vision is not working right. Typical school vision screenings may miss the problem also.

The near vision system is a balance of several processes…

So what are the mechanisms involved in near vision focusing??

There are 3 processes involved in near vision focusing. Optometrists call it the near vision triad.

1) Pupil constriction- as an object moves closer, the pupils constrict to improve focusing of incoming light on the fovea. The fovea is an area on the retina with the highest density of light receptors. This area gives us our most acute vision.

2) Convergence– as an object moves closer, the eyes move toward the nose to keep the object on the fovea. Both eyes should smoothly convergence together as the target moves closer.

3) Accommodation– lens of the eye focuses- In humans under 40 years old, the lens of each eye changes focus as objects move closer. This is much like a camera lens. As children, the lens is very flexible allowing for a large focusing range. After 40, the lens tends to become less flexible, so we may need glasses to help see clearly up close

Heres a video that puts it all together.

As something moves toward us, the brain adjusts with the right amount of accommodation and convergence, in addition to the pupil constriction.

What does it look like when it does not work right??


This is easy to screen using the Near Point Convergence test .  

Only the optometrist can identify these problems, but as therapists, teachers and parents, we need to be aware of the signs of near focusing problems. The Convergence Insufficiency Symptom Survey  is a well researched tool that is very effective in identifying patients with possible CI.

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