Intermittent exotropia is the most common type of strabismus, with a prevalence of about 2% in children under 3 years of age, usually in response to inattention or fatigue. Most patients develop exotropia with increasing frequency, thus affecting the development of stereo vision. Previous treatments for intermittent exotropia have been divided into two categories: surgical and non-surgical. Surgical treatment consists of 2 main types of treatment, posterior migration/removal in one eye or posterior migration of the external rectus muscle in both eyes. Non-surgical treatments include masking, glasses, pooling exercises, and Botox injections. So what is the best treatment option for intermittent external strabismus? A systematic review by Kerry E Joyce, a British researcher, found that: 1. Pre-operative treatment with masking or post-operative visual training for strabismus correction is more effective. 2. Non-surgical interventions are less effective than surgical treatment in correcting exotropia. 3. In terms of pure surgical treatment, posterior migration of the external rectus/internal rectus osteotomy in one eye is relatively effective in the short term, but the results may regress in the late stage.