This is usually a sign of ptosis, a very common condition in ophthalmology. It is a condition that results from underdevelopment or loss of function of the levator muscle. There are two main causes of this condition: congenital genetic factors and acquired eye diseases. For example, orbital occupational disease, ophthalmic nerve palsy, and myasthenia gravis. Therefore, treatment options should be chosen according to the severity and cause of the condition. For congenital ptosis, surgery is usually the main treatment, while for acquired ptosis, conservative treatment is required depending on the cause. In cases where conservative treatment is ineffective for more than six months, surgery should be considered. The two most commonly used surgical procedures are levator muscle shortening and frontalis suspension.