Exercise induced esotropia.

A case of unusual intermittent esotropia and diplopia is reported. A 13-year-old boy experienced diplopia during vigorous exercise that resolved within 30 minutes after stopping the exercise. The symptoms had been present unchanged since age 6. Examination revealed orthophoria. After vigorous exercise an esotropia of 14 prism diopters in the distance developed, which gradually resolved over 30 minutes. Neurologic evaluation, CT scan, and magnetic resonance imaging scan have been normal. The symptoms have continued unchanged for 11 years. To my knowledge, no other similar case of exercise induced esotropia has been reported.