Convergence insufficiency is a condition in which your eyes are unable to work together when looking at nearby objects. This causes one eye to turn instead of teaming with the other eye; thereby creating double vision, blurred vision, or for the information to move off center.
Convergence insufficiency is usually diagnosed in school-age children and adolescents. It can cause difficulty reading, for which parents or teachers might suspect the child has learning difficulties rather than an eye disorder.
Treatments are usually effective for convergence insufficiency.
Symptoms
Not everyone with convergence insufficiency has signs and symptoms. Signs and symptoms occur while you’re reading or doing other close work and might include:
- Tired, sore or uncomfortable eyes (eyestrain)
- Headaches
- Difficulty reading — words seem to float on the page, losing place, or slower reading
- An aversion to reading or completing assignments
- Double vision (diplopia)
- Difficulty concentrating, agitation when asked to sit still or focus, ADHD/ADD like symptoms
- Squinting, rubbing eyes, closing one eye, head tilt or covering an eye with their hand
- Writing uphill or downhill
When to see an Optometrist
If you or your child has symptoms of convergence insufficiency, problems reading, or difficulty focusing on near work, consult a behavioral optometrist.
Causes
While the underlying cause of an idiopathic patient is unknown, there seems to be a genetic correlation. Many patients who go through our program, will also have a sibling or child go through with or after them. If a patient has had a traumatic brain injury, they may develop secondary convergence insufficiency as well. The main symptom is a misalignment of the eyes when focusing at near. Typically, one eye drifts outward to alleviate the double or blurred vision.
Complications
Convergence insufficiency does not cause learning disabilities, but it makes using your eyes difficult and tiring. Due to the strain at near, reading and concentrating can be affected.
Unfortunately, convergence insufficiency isn’t typically detected in school screenings or routine eye exams. Therefore, most children with this diagnosis, end up with an evaluation for learning disabilities or ADD/ADHD. This is why it is important to bring your child to a behavioral optometrist to rule out a developmental eye disorder.
Diagnosis
While people with convergence insufficiency might have 20/20 vision, be sure to mention reading or learning concerns to your eye care provider. To diagnose eye disorders such as convergence insufficiency, your eye doctor might:
- Take a medical history including questions about problems with focusing, blurred or double vision, headaches, symptoms, and how it affects a child’s school performance.
- Measure the near point of convergence (NPC) which is the distance from your eyes to a focal point without blur or diplopia.
- Assess positive fusional vergences (PFV) at near and far. The examiner will note the point of break and recovery.
- Measure fixation disparity, test Base In/Base Out amplitudes with a polarized vectogram, and measure accommodative abilities with a +/-2.00 accommodative flipper.
- Perform a comprehensive eye exam with dilation.
Any vision issues your optometrist finds might lead to additional testing to assess the severity of the problem.
Treatment
Treatment for convergence insufficiency takes place in the office of a trained therapist and at home, might include:
- Pencil push-ups
- Brock String
- Polarized vectographic training
- Computer vision therapy
- Reading with a flipper
Recent studies show that office-based therapy with home-based exercises is the most effective treatment. Home-based treatment with pencil pushups, computer programs, and/or YouTube videos is not as effective as a specialized treatment plan.
Convergence insufficiency should take 3-6 months to treat. While the prognosis is good, symptoms might recur after injury, illness or a lot of reading/near work.