Convergence insufficiency is a binocular condition that results from the inability of the eyes to turn in enough when looking at a near object. Typically, when fixating on a near object, the eyes will turn in, or converge, to keep the object single and clear. If the eyes are unable to converge enough, then eye strain, headaches, or double vision can occur. These are all common symptoms of convergence insufficiency. Treatment for convergence insufficiency includes glasses or vision therapy. Glasses may be used for reading or other near tasks only or can be worn full-time.
Why the Eyes Converge at Near
When focusing on a near object – such as reading or using a computer – the eyes must turn inward to the nose to keep the object clear, focused, and single.
Looking at the distance, the eyes can be aligned while straight ahead and focusing on the target. As the object that is being focused on gets closer to the eyes, the eyes must turn inward to keep the target focused.
The center of vision comes from the area of the retina called the macula. This region of the retina creates the best vision and is responsible for fixating on targets.
In order to keep the macula looking at the desired target, the eyes must turn inward to fixate on near objects.
Problems with Convergence
If the eyes struggle to turn inward, there is likely an issue with the convergence system of the eyes.
There can be issues with the ability of the eyes to turn inward while keeping vision clear and single.
If the eyes are unable to converge and have a single, clear image, there must be some adaptation – either the eyes do not converge, vision is blurred, or vision is double.
Even if the eyes are able to converge with a single and clear vision, it is possible that the strain of trying to keep the system in place creates undue stress on the eyes.
Symptoms of Convergence Insufficiency
If convergence insufficiency is present, the eyes’ ability to turn inward is decreased. As a result, the convergence system is disrupted.
Some symptoms of convergence insufficiency include double vision near or when reading, headaches and eye strain, and blurry vision near but clear vision in the distance.
All symptoms of convergence insufficiency are worse near than in the distance since that is where the majority of convergence is needed.
Treatment for Convergence Insufficiency
The two main treatments for convergence insufficiency are glasses and vision therapy. Glasses are considered a passive treatment as the problem is not remedied but the symptoms are alleviated due to using the glasses.
On the other hand, vision therapy is an active treatment as the actual problem with the eyes is being altered and corrected.
Both glasses and vision therapy can provide excellent outcomes based on the needs of the patient. Discussing goals and symptoms with your eye doctor is a great way to make an informed decision on the best option for treatment.