The width of a normal adult eye is 30 to 34 mm, the distance between the inner canthus of the two eyes is 30 to 32 mm, and the upper and lower lid fissures are 10 to 12 mm in diameter. There are two causes of narrow lids: 1. Congenital microphthalmia Congenital microphthalmia is a congenital abnormality of the lid that is hereditary in nature and is often combined with medial canthus and ptosis. Small lids can be corrected by canthoplasty, and congenital microphthalmia should also be corrected by endophthalmos and ptosis. The most common type of exophthalmoplasty is the Von Ammon method, which permanently opens the lid cleft, and we have improved the Von Ammon method to achieve better results. 2. Traumatic or infected canthal margin adhesions can be treated with local reshaping, flaps, or implants.