Convergence Insufficiency - An Overview

Introduction

Convergence insufficiency is an eye condition in which the eyes cannot point inwards while seeing a close object. It can affect children and adults and involves symptoms such as double vision, headache, and blurred vision. Different eye exercises can treat convergence insufficiency. Read the article to learn more.

What Is Meant by Convergence Insufficiency?

Convergence insufficiency is an eye condition that involves binocular vision (vision of both eyes). Convergence is the movement of the eye that points inward when the person looks at a nearby object like a phone, books, etc. With this condition, there will be an eye coordination issue where the eye points outward as the person looks at a nearby object. This can result in double or blurred vision.

This condition is very common in adults but can affect people of any age. This condition can be managed through eye exercises, and special glasses can be used to manage the symptoms temporarily. About two percent to 13 percent of people in the United States are affected by this condition.

What Are the Symptoms Related to Convergence Insufficiency?

Some common symptoms related to these conditions are

• Tired eyes.

• Double vision.

• Blurry vision.

• The problem is concentrating.

• Headaches.

• Dizziness.

• People may find reading difficult as they see the words floating around.

If convergence insufficiency is present in children, then the symptoms exhibited are

• Squint eyes.

• Rubbing the eyes.

• Closing the eyes to get a proper image.

What Are the Causative Factors of Convergence Insufficiency?

The main cause of convergence insufficiency is the lack of communication between the nerves and the muscles, which control the movement of the eyes. The eye muscles are usually healthy, but the nerves that control them are not sending the correct message to the eye to point inward while viewing a close object. In case of convergence insufficiency, both the eyes point away from the viewing object. In some rare cases, brain injury or a neurodegenerative condition like Parkinson’s condition can result in convergence insufficiency.

How Is Convergence Insufficiency Diagnosed?

Initially, the doctors perform a complete eye examination and review the person's medical history. Usually, people can pass through the standard exam even though they are affected by this condition. There is a special test to see if the eye converges while looking at a nearby object. The doctor also conducts some tests to measure:

• How much does the eye point towards the nose before the person has double vision?

• How much does the eye turn when the person looks at things present close?

• How well can the eye switch from focusing while things present close to far away?

How Is Convergence Insufficiency Managed?

This condition is usually treated through eye exercise that helps the nerves properly aim at the eyes. These exercises help enhance the eye's ability to move inward by viewing objects at various distances. These exercises will be performed with the help of a therapist initially and should be continued at home.

In some cases, specialized glasses, called prism glasses, need to be used. These glasses usually redirect the light that reaches the eye and work the nerves. The changes will be seen after doing the eye exercises; it usually takes about 12 weeks to see visible changes. These symptoms can reoccur if the person is sick, not getting good sleep, or doing many close-up activities.

Studies are being performed to find better ways to treat this condition, such as new eye exercises or virtual reality headsets. If exercise therapy does not work in rare conditions, it must be treated through surgery. This surgery is performed on the eye muscle. This is a very rare option and can result in complications such as esotropia (where one eye turns inward).

What Is a Dot Card Exercise?

Convergence insufficiency conditions can be managed through various eye exercises. The dot card eye exercise is one such exercise. This is done by holding a card lengthwise so that the tips touch the nose. The line of dots over the card should be in front of the nose. The person will be asked to view the furthest dot. If the eyes of the person convert correctly, then the viewed dot will be seen singly, and the remaining dots will form an A shape.

What Are the Complications Related to Convergence Insufficiency?

The common complication caused by this condition is the discomfort it creates and causes disturbance with activities that involve near vision. In some people affected by this condition, the brain will switch off the vision in one eye to avoid double vision. This is because both eyes do not work together. Some complications other than discomfort are:

• Lack of coordination among the two eyes.

• Bad judgment of distance.

• The person finds it difficult to play sports.

• Motion sickness.

• Difficulty in making eye contact.

What Are the Risk Factors Related to Convergence Insufficiency?

People affected by brain injury can develop convergence insufficiency. There are no other risk factors. This condition cannot be prevented, as doctors are unclear about the cause of poor muscle coordination.

When Should the Affected Person Consult the Doctor?

Parents should take their child to the healthcare provider as soon as they notice any symptoms related to convergence insufficiency when the child performs an activity that involves close-up work, such as reading.

What Are the Differential Diagnosis Related to Convergence Insufficiency?

Some differential diagnoses are:

• Untreated refractive errors such as farsightedness or over-minus nearsightedness.

• Accommodative insufficiency is the inability to sustain focus at near.

• Convergence paralysis is the onset of diplopia.

Conclusion

Convergence insufficiency is an eye condition in which the eyes cannot point inward while seeing a nearby object. It can be seen in children as well as adults. This condition causes discomfort and does not allow the person to see an image clearly. Although it cannot be prevented, it can be treated through various eye exercises that help strengthen the eye muscle.