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*DID YOU KNOW?  Binocular vision problems are common and they can impair reading, writing, and learning?

A Binocular Vision Disorder/Dysfunction is when your two eyes aren't teaming together properly. 

If you are thinking that Amblyopia and Strabismus belong in this definition, then you are correct, but for the purpose of explaining all the other types of binocular dysfunctions, we will leave them out of the discussion in this page. 


If you want to know how we treat those disorders, click here. 

On this page, we'll discuss the types of eye teaming problems that tend to have affects on patient's lives, yet do not fall under those categories of Amblyopia/Strabismus/'Lazy Eye.'


The movements and the posture of the eyes are controlled by 6 muscles called extra ocular muscles.  These muscles attach to outside globe of the eyeball and pull it in different directions depending on what signal they get from a motor neuron (Cranial Nerve) from the brain.  These muscles do not have to be very strong but they have to be extremely precise.  

Let's contrast these muscles to the Gastrocnemius muscle in the leg.  Every motor neuron that connects to this Gastrocnemius muscle will reach about 2000 muscle fibers.  This makes for a very strong force with little precision.  To contrast, each neuron reaching the extraocular muscles only connects to 3 muscle fibers at a time.  So when there are so many neurons (each coming from the brain) there is a lot more room for error.  When these errors occur, one eye may have a slight tendency to turn a little less or slower than the other eye.  

There are many variations of errors between the posturing of each eye and some of the more common ones are listed below:

  • Convergence Insufficiency: While reading or viewing near targets, your eyes will not pull inward enough.

  • Convergence Excess: While reading or viewing near targets, your eyes will pull inward excessively.

  • Hyperphoria: A tendency of one eye to tilt up in the socket higher than the other.

  • Divergence Insufficiency: When viewing distant objects, your eyes will not diverge enough.

  • Divergence Excess: When viewing distant objects, your eyes will diverge excessively.


  • Headaches 

  • Double vision 

  • Eye strain

  • Difficulty with attention

  • Difficulty completing tasks on time

  • Fatigue and feeling tired at school or during visual tasks like reading/writing/computer work

  • Poor self esteem

  • Car sickness

  • Sensory and motor problems

  • Difficulties learning and in school

  • Slow reading

  • Difficulty driving, especially at night

  • Skipping over words or whole lines of text when reading

  • Excessive need for using your finger during reading

  • Blurry vision

  • Appearance of text moving or "jumping around" on a page or screen


These problems can be diagnosed quickly within the setting of a general eye exam, but your eye doctor has to be looking for them.  If your eye care doesn't run specific tests during the eye exam, then it will be missed.  

For this reason, if you or someone you know have some of those symptoms listed above, the best thing to do is to schedule a complete Neuro Optometric Evaluation where we will take the time to do all the testing needed to diagnose these problems, figure out the severity, and develop a treatment plan.   



Treatment of almost all Binocular Vision Dysfunction includes one or a combination of the following:



In rare cases, surgery may be indicated. 

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