Convergence Insufficiency

Convergence Insufficiency or Convergence Disorder is a sensory and neuromuscular anomaly of the binocular vision system, characterized by an inability of the eyes to turn towards each other, or sustain convergence.

Symptoms

The symptoms and signs associated with convergence insufficiency are related to prolonged, visually-demanding, near-centered tasks. They may include, but are not limited to, diplopia (double vision), asthenopia (eye strain), transient blurred vision, difficulty sustaining near-visual function, abnormal fatigue, headache, and abnormal postural adaptation, among others. Note that some Internet resources confuse convergence and divergence vergence dysfunction, reversing them.

Diagnosis

Diagnosis of convergence insufficiency is made by an eye care professional skilled in strabismic dysfunctions to rule out any organic disease. Convergence insufficiency characterized by one or more of the following diagnostic findings: High exophoria at near, reduced accommodative vergence/accommodation ratio, receded near-point of convergence, and/or low fusional vergence range.

Treatment

Convergence insufficiency may be treated with convergence exercises prescribed by an eye care specialist trained in vision therapy, orthoptics, and binocular vision anomalies. Some cases of convergence insufficiency are successfully managed by prescription of eyeglasses in addition to the therapy regime.

Also, the use of computer software can exercise the insufficiency at home in a uniform manner.

Currently a study is underway by the Pedig Group and the Jaeb Center to determine the best way to treat convergence insufficiency. ESC is a part of this study.


Prevalence

Studies conducted by the Southern California College of Optometry found that approximately 1 in 8 (13%) of fifth and six grade children examined during visual screenings had the disorder as did nearly 1 in 5 (17.6%) of 8 to 12 year olds receiving regular examinations at optometry clinics.