Convergence Insufficiency / Exophoria

Related to the subject of eye exercises, there is a well described form of strabismus called Convergence Insufficiency or Exophoria.  This form of strabismus is easily detected through an eye examination, and we pediatric ophthalmologists actively screen for it in our patients.  For some people this strabismus is merely an incidental eye finding, and there are no symptoms.  Other patients (adults in particular) may complain bitterly of any of the following symptoms after prolonged reading:  eye fatigue, blurred vision, double vision or headaches.  The resulting discomfort with reading arises from an inability to keep the eyes turned inward (converged) for close work.  This is the one ophthalmic condition in which simple eye exercises may be helpful.

The good news about convergence exercises is that the patients in this practice are taught how to easily perform these exercises at home.  There are no costs involved, and performing them will take less than five minutes out of your day.  Patients are provided with directions and a few basic tools to carry out convergence exercises.  The purpose of the exercises is to increase the amount of time the eyes can maintain an inward position to view close objects.

Another activity that strengthens the convergence mechanism is reading and typing on smart phones or other small handheld tablets.  This “exercise” is only half-heartedly suggested for convergence insufficiency knowing that most parents want to reduce their child’s screen time.  It is worth noting that if your child spends hours playing on a handheld device without headaches or visual complaints, he or she doesn’t have convergence insufficiency.

The closer an object is to the eyes, the greater the convergence effort required.  The normal reading distance is 12 – 14 inches.  Anything closer requires more crossing of the eyes to maintain the image.  Desk top computers are therefore much less likely to cause convergence insufficiency complaints because they are at arm’s length.

If convergence exercises do not control symptoms within a few weeks, base-in prism glasses can be considered particularly for the student with extensive reading requirements.  Prism glasses allow the eyes to view close material with the eyes parallel, eliminating the symptoms derived from a prolonged convergence effort. 

Convergence insufficiency can be associated with other forms of strabismus such as intermittent exotropia where the eyes overtly deviate in the distance.  Overt ocular misalignment needs to be ruled out by your ophthalmologist as the work-up or treatment may vary depending of the form of eye muscle disorder.  If convergence exercises are not working, a return visit to the eye doctor is advised.