There are congenital and acquired ptosis, but congenital ptosis is more common bilaterally and can be hereditary, either dominant or recessive. The main cause is hypoplasia of the nucleus accumbens or hypoplasia of the levator muscle, which is often associated with extraocular muscle paralysis or canthus in addition to ptosis, while the latter is usually a simple ptosis. Ptosis can be unilateral or bilateral and can be congenital or acquired, and the degree of ptosis can be classified as complete, incomplete or pseudo-pituitary. Many acquired lesions can involve the levator muscle or the branch of the motoneurotic nerve that innervates the levator muscle and lead to ptosis, which can be broadly grouped into three categories. 1. mechanical factors: mainly inflammatory swelling of the upper lid, mass growth, and excessive fat deposits that increase the weight of the upper lid and prevent the levator muscle from lifting the upper lid sufficiently. 2. Myogenic factors: In severe myasthenia gravis it may simply manifest as ptosis in the upper lid with surgical contrast ptosis correction, either bilaterally or unilaterally. It is characterized by lightness in the morning and heaviness at night, and can sometimes be accompanied by weakness of other extraocular muscles. The diagnosis is more easily established in ptosis caused by direct surgical or traumatic injury to the levator muscle. 3. Neurogenic factors: These are seen in various causes of motoneuropathy. Mild ptosis can also occur in Horner’s syndrome caused by sympathetic nerve palsy. Eyelid ptosis can be treated surgically either unilaterally or bilaterally, but candidates need to understand that it is unrealistic and difficult for the surgeon to achieve if the surgery requires absolutely uniform results in both eyes. Because ptosis involves the strength of your eye lifting muscles, the affected eye and the normal eye will have problems with eye size or incomplete eye closure when the surgery is first completed, and will gradually return to natural in about six months. It is important to remind you that; upper eyelid ptosis surgery is not a simple double eyelid surgery and requires an experienced surgeon to perform the treatment in order to grasp the scale of treatment and achieve the best results between operations.