Opening the inner corner of the eye is a kind of plastic surgery, which is used to correct microphthalmia. It is necessary to enlarge the medial canthus and lateral canthus, fix the medial canthus ligament to correct the widening of orbital distance if necessary, or correct ptosis. Congenital microphthalmia is characterized by narrow palpebral fissure and serious epicanthus, which is often accompanied by widening epicanthus distance and ptosis. The operation needs to be carried out by stages. The operation period should be in preschool age, when the development of nasal bone has been gradually improved, and the appearance, especially the medial canthus spacing, may be improved.