Convergence insufficiency (CI) is a common childhood eye-teaming problem in which the eyes have a strong tendency to drift outward when reading or doing close up work. Children with CI have more symptoms and a shorter attention span when reading than children without CI.
A child’s eyes must turn inward, or converge, in order for words on a page to appear in focus. With CI, the eyes don’t converge easily and result in the child using additional muscular effort to make the eyes turn in.
Convergence and Accommodation
Convergence may be thought of as the ability to cross the eyes. Every time we perform tasks such as reading or using a computer, we use this ability. That’s because when we look straight ahead and far away, the eyes should be essentially in parallel alignment. When the object gets closer, the eyes must turn inward to keep each of them correctly aimed where they should be. We must also increase the focusing power to keep an up close image clear. This is called accommodation.
Convergence and accommodation are linked in the brain so that, when a child shifts from distance to near, they reinforce each other and keep the image single and clear without either of them needing extra help.
Small amounts of inadequate convergence are expected, especially for seeing close up. A child with CI must use extra effort to avoid seeing double and this extra effort can lead to annoying symptoms. Parents should look for the following indications that their child may have this vision problem.
- eye strain
- blurred vision
- double vision
- loss of concentration
- frequent loss of place when reading or working up close
- reading slowly
Treatment using office-based accommodative-vergence vision therapy can improve symptoms in children affected by CI. The majority of eye care professionals treat children diagnosed with CI using some form of home-based therapy, but a new study concludes that office-based treatment by a trained therapist, along with at-home reinforcement, has a greater effect.
After a 12-week study, nearly 75 percent of children who participated in the office-based vision therapy, in combination with at-home reinforcement, achieved normal vision or had considerably fewer CI symptoms.
CI has no visible signs and can only be detected and diagnosed during an eye examination. If you suspect your child may be experiencing vision problems of any kind, take him to your eye care professional for a complete eye exam. Your eye doctor can then advise you as to what options are available to correct any vision problems that may be found.