Convergence Insufficiency

Convergence Insufficiency is a reduced ability to bring the eyes together for near vision tasks.

In order to read and focus at near, the visual system is required to make a single clear image by bringing the eyes closer together, this usually being stimulated when a person looks down and close. If this does not occur then a blurred double image would be the result, or the brain would switch one eye off to cope, this is termed Suppression or Amblyopia.

In many cases the reduced ability to bring the eyes together for near vision tasks is related to focus insufficiency. That is, many children have reduced convergence being linked to inefficient focus for near vision affecting awareness of where to aim the eyes, this due to developmental delay in their focus stamina.

In cases of focus issues being linked to the convergence insufficiency, therapeutic spectacle lenses are often all that is required to improve both the focus delay and convergence ability.

These Therapeutic spectacle prescriptions are most commonly dispensed in multifocal form, so that assistance may be given for near vision without disturbing distance vision. This is necessary in a classroom situation for children or office situation for an adult so as to allow smooth transition of focus between distance and near tasks.

Usually single vision lenses, although beneficial for near, become problematic in the distance as the individual is then looking through a prescription they do not require when trying to look at the blackboard. So benefit at near can be negated by the distance blur, leading to further eyestrain and compliance issues.

In cases of convergence insufficiency which are more related to the ability of the visual system to turn the eyes inward then a program of Vision Therapy may be required to retrain the eye muscles to converge. This is usually due to a developmental delay in the flexibility, co-ordination and integration of the eye muscles that move the eyes in whichever direction we are to be looking.

In more longterm cases of convergence insufficiency, it is common to find an Exotropia also being present, where one eye fixates and the other remains slightly divergent, ie an outward eye turn.

Often a combination of Vision Therapy and Therapeutic Spectacle Prescriptions are required to manage cases of Convergence Insufficiency.