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Binocular Vision Dysfunction (BVD)

What is Binocular Vision Dysfunction (BVD)?

Binocular vision dysfunction (BVD) is a visual condition where the line of sight from one eye tends to be slightly out of alignment with the line of sight from the other eye (usually vertical) and this puts heavy strain on the eye muscles as they are constantly trying to correct the alignment to achieve single focus vision.

The cause can be secondary to: normal facial asymmetry, acquired facial asymmetry from aging or head trauma from sports or injury damaging the nerves to your eye muscles causing the imbalance.

This heavy strain on the eye muscles results in dizziness, headaches, disorientation and reading difficulties. Some people suffer from only one symptom while others from multiple; which is why it can be so difficult to diagnose.


There are three forms of BVD:

  • Vertical Heterophoria
  • Superior Oblique Palsy
  • Horizontal Misalignment

Abstract blurred background with bokeh of lightThe corrective measures taken by the eye muscles in order to keep the lines of sight aligned, i.e. vision that is not blurred or double, results in overuse of the eye muscles making them strained and fatigued which results in many of the symptoms of BVD.

An additional corrective measure taken by the brain to achieve single focus vision is for the head to tilt slightly resulting in neck pain and other BVD symptoms. Head tilt is known to occur in Vertical Heterophoria and Superior Oblique Palsy to minimize misalignment and avoid double vision.

Doctors Penza and Morioka, have completed a comprehensive externship in the field of BVD and are now treating patients for this condition. You may book an appointment with them directly by contacting the practice.

Before scheduling an appointment, please click here to complete the online test to determine if you could be suffering from BVD. This test will be analyzed by a vision specialist.

People From Around the US Come to Be Treated!

Girl covering one eye with palm for eyesight examSymptoms of BVD

Those who suffer from Vertical Heterophoria or Superior Oblique Palsy tend to have a small amount of vertical eye misalignment, which the brain corrects by directing the eye muscles to properly reposition the eyes. However, using the eye muscles in this manner overworks them and they become strained and fatigued, causing the many symptoms of Vertical Heterophoria and Superior Oblique Palsy:

  • Anxiety in crowds or large open spaces
  • Overly sensitive to light and glare
  • Double vision
  • Shadowed, overlapping or blurred vision
  • Skip lines or lose your place while reading.
  • Quickly fatigue while reading and difficulty with comprehension.
  • Closing or covering one eye to make it easier to see.




  • Headaches
  • Dizziness
  • Lightheadedness
  • Nausea
  • Anxiety
  • Motion sickness
  • Poor depth perception
  • Lack of good balance and drifting while walking
  • Poor coordination and Clumsiness
  • Aching eyes, especially with eye movement
  • Neck, upper back or shoulder pain
  • Head tilting

Diagnosis & Treatment

How do you know if you are suffering from BVD?

Researchers have devised a specialized questionnaire that will evaluate if you might be suffering from any form of BVD.

Prismatic lens treatment offers a substantial reduction in BVD symptoms.

Using realigning prismatic spectacle lenses, the strain and fatigue within the visual system is reduced or eliminated. The average person experiences a 30-50% reduction in symptoms almost immediately and a 70-80% reduction of symptoms over the course of the several visits as the prismatic prescription is fine-tuned and customized for the individual.

The treatment is for a short period of time, with the average person completing the treatment in just 2 to 3 months. Learn more when you visit our optometrists'  Dr. Vincent Penza and Dr. Katherine Morioka, O.D.

More info on BVD:

Click here to read more about BVD.


Fill Out Our Questionnaire to see if you have BVD
Fill Out Our Questionnaire to see if you have BVD