Children particularly take less precautions as compared to adults, therefore they experience convergence inefficiency more commonly than adults these days, says Dr Smita Kapoor

In today’s digital age, using different screens is perhaps unavoidable. During the pandemic because people could not go outdoors and had to maintain physical distancing, mobiles and laptops became everyone’s recourse. Like adults, children's screen time has also increased for various reasons. Children study online, use screens for gaming and entertainment, have video conversations with friends on mobile phones and use social media for hours. While this increased screen time causes eye strain, it also leads to an eye condition called convergence insufficiency. For this reason, we must try to minimize our screen time as much as possible and also take sufficient precautions when letting children use screens.

What is convergence insufficiency?

Convergence insufficiency is an eye disorder in which the two eyes cannot synchronize and work together when focusing at nearby objects. In this condition one eye may drift outward when trying to focus on an object brought up close, leading to blurred or double vision. This makes reading and focusing difficult and also causes frequent headaches. The condition usually starts in childhood but can even affect adults. Some of the factors that lead to convergence insufficiency are concussions, neurodegenerative conditions such as Alzhiemer’s, Parkinson’s or Graves’ disease.

What is the connection between screen usage and convergence insufficiency?

Since most screens are used at close distances, convergence insufficiency becomes a natural outcome. Children particularly take less precautions as compared to adults, therefore they experience convergence inefficiency more commonly than adults these days.

What are the symptoms of convergence insufficiency?

Some of the symptoms that might indicate the presence of convergence inefficiency are headache, strain, eye fatigue, difficulty in reading and concentration, double vision and the frequent need to squint or rub the eyes. At the same time clues such as a child avoiding sports that require depth perception or having trouble in catching objects thrown through the air, being prone to frequent stumbling on uneven surfaces or bumping into furniture etc due to poor judgment of distance must be strong signs of troubles related to convergence insufficiency.

Is it true that convergence insufficiency is different from far-sightedness and lazy eye?

Convergence insufficiency is the inability to maintain binocular function while far-sightedness is a refractive error in which a person cannot focus on and see nearby objects clearly because the length of the eyeball is short or the cornea is flat. Convergence insufficiency is also different from amblyopia or lazy eye in which poor vision in one eye if left untreated for a long time leads to the constant use of the good eye. As a result, the former becomes weaker with the passage of time.

What should one do when faced with convergence insufficiency?

First and foremost, children must be supervised closely so that a sufficient balance is ensured between their screen time and non-screen time.

Second, sufficient distance should be maintained between the eyes and the screen.

Third, children could be made to do a series of ocular exercises prescribed by a trained ophthalmologist. A focusing exercise is pencil push-ups in which the child is made to focus on the tip of a pencil while bringing the pencil closer to the bridge of the nose and stopping just when the object becomes double. Another one is a software based exercise that can be done on a computer at home under parents’ supervision. If exercises do not help, prism glasses could be given to the child.  And the last option is eye muscle surgery.

Therefore, at the slightest doubt of a symptom of convergence insufficiency, one must consult a squint specialist immediately.

The writer is Consultant Paediatric Ophthalmology and Strabismus, Vision Eye Centre, New Delhi