The main causes of exotropia are as follows: 1. Refraction-related and disuse exotropia: Usually the human eye keeps the eye in a positive position through the ability to collect, while the resting position of the human eye is often in an exotropic state. Some patients with myopia have poor adjustment and collection ability, and the human eye will gradually have a tendency to exotropia, which is refraction-related exotropia. This part can be corrected partly through optometry, while a part of the exotropia may not be corrected through prescription lenses, may need to be treated through surgery. 2, trauma disease causes: some trauma or cardiovascular disease caused by exotropia, such as orbital fracture caused by muscle inlay, cardiovascular accidents caused by nerve paralysis can also cause exotropia.