What is convergence insufficiency?
Convergence insufficiency happens when the eyes are not able to work together to look at close objects. Typically, one eye has a tendency to turn outward (intermittent exotropia) when focusing close up.
What is the difference between convergence insufficiency and exotropia?
With intermittent exotropia, the eyes do not work together at both near and far distances. In convergence insufficiency, only near vision is affected.
What symptoms are associated with convergence insufficiency?
- Diplopia (double vision)
- Headaches when reading
- Difficulty concentrating on near work (computer, reading, etc.)
- Movement of words on the page
- Blurred vision after prolonged periods of reading
- Eyestrain (especially with or after reading)
- Frequent loss of place
- Sleepiness during near work
How is convergence insufficiency diagnosed?
A diagnosis of convergence insufficiency is made by an eye doctor after taking a history of the patient’s symptoms and measuring convergence ability. An essential component of the exam includes measuring the near point of convergence (the ability to use the two eyes together at an increasingly close working distance). Your doctor will also check for uncorrected refractive error (need for glasses), eye muscle dysfunction, and poor accommodation (difficulty with near focusing).
Does every patient with convergence insufficiency require treatment?
During a routine eye examination, convergence weakness may be diagnosed even if a child has no symptoms. This may be the result of true convergence weakness, but is often found when the patient is distracted, shy, overly excited or does not understand the directions given. These patients should either be retested at another time or simply watched for symptoms of double vision or headaches with close task. A patient who is not having difficulty, but tests positive for convergence insufficiency in the office does not need treatment but should be followed.
What is the treatment for convergence insufficiency?
- Vision therapy convergence exercises
- Pencil push-ups or other convergence vison therapy such as vectograms, tranaglyphs, barrel cards, eccentric circles, etc.
- Base-out prism glasses increase the difficulty of convergence activities
- Base-in prism glasses are occasionally prescribed to temporarily align the eyes for reading, but these are not a long-term solution
- Computer program convergence exercises
Is convergence insufficiency treatment always successful?
Occasionally, a patient will not respond to therapy. In these cases, prism glasses may be prescribed for reading. Prism glasses artificially align the eyes and allow for more comfortable binocular vision (vision with two eyes). In rare cases, surgical intervention may be suggested.
Is convergence insufficiency permanent?
Symptoms related to convergence insufficiency are often better following exercises that improve convergence abilities. Occasionally, symptoms may recur after illness, lack of sleep or increased close-up work demands. If treatment was successful previously, an additional course of treatment tends be effective at resolving symptoms.