A large proportion of concussion patients with long-term consequences of concussion experience visually related symptoms such as headache, blurred vision, double vision, and fatigue.

These patients often have difficulties coordinating the movement of the two eyes (convergence insufficiency) which is essential for single and clear vision to be obtained and is hence a likely explanation for the symptoms.

100 patients with long-term symptoms of concussion and convergence insufficiency will be offered either exercises or placebo treatment the evaluate the effect of exercises aimed at improving coordination between the two eyes.

The study will provide data to support clinicians in deciding whether to use exercises or not as a treatment of symptoms for patients with convergence insufficiency as a long-term consequence of concussion.

Inclusion Criteria:

• Concussion at least 3 month ago
• Convergence insufficiency which has not been diagnosed prior to the concussion

Exclusion Criteria:

• Patient who are unable to fulfill baseline examination
• Manifest or paralytic strabismus
• Self-reported eye disease