Binocular Conditions

Amblyopia   Convergence insufficiency   Strabismus

Binocular disorders are a group of conditions in which the two eyes have difficulty tracking in sync with each other. We humans have a wide angle of view; we have precise depth perception; and we are able to identify very faint objects. About 20% of the population has some form of binocular imbalance. As many as 56% of those aged 18–38 have some form of binocular limitation, which may be so mild that it is not apparent without testing. The causes range from insufficient development of the vision system in early childhood, to genetically-based nervous-system impairments, to injury, and even to aging.

Vision therapists define various eye movements and orientations systematically as follows:

  • Exophoria is when the eyes tend to diverge away from the centerline of vision.
  • Esophoria is when the eyes tend to converge toward the center axis of vision.
  • Convergence means that the two eyes simultaneously look inward.
  • Accommodation is the ability of the eye to focus, linked to convergence by a reflex.
  • Fusion refers to the ability of the visual cortex to convert two images, one input from each eye, into one viewed image.

    • Binocular Vision Disorders

    Amblyopia is the most common type of binocular disorder in which one eye takes in less information than the other.

    Strabismus is another binocular disorder in which one eye is misaligned, relative to the other, in a variety of ways. Strabismus can cause amblyopia.

    Convergence insufficiency occurs when the eyes have difficulty holding a point of convergence while doing close work. They tend to drift outwards resulting in blurred or double vision.

    Accommodative insufficiency simply means that the eye is unable to focus or maintain focus.

    Accommodative infacility means that the eye has difficulty changing focus rapidly enough for comfortable functioning.

    Fusional vergence dysfunction is the inability to efficiently utilize and/or sustain binocular vision. One diagnostic clue is that the patient will have difficulty using several types of vision therapy prisms. There are positive (convergence) and negative (divergence) types of this disorder.

    Complementary Approach

    Nutrients and diet can help support overall vision health, but they do not replace the need for vision therapy or recommended procedures.

    Binocular Conditions News

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