I. What is a blepharoplasty? A blepharoplasty is the term used to describe a single eyelid. Single eyelid means that the skin of the upper eyelid is smooth from the lower edge of the eyebrow arch to the lid margin, and when the eyes are opened, there is no crease formation known as a single eyelid, commonly known as monocleid. Blepharoplasty refers to the upper eyelid skin above the lid margin has a shallow groove, when the eyes open this groove below the skin upward, while the skin above this groove is loose in the blepharoplasty groove hanging downward folded into a horizontal skin fold, heavy eyelids, commonly known as double eyelids. In people’s minds, the difference between double eyelids and single eyelids is obvious. In fact, there are aesthetic differences, morphological differences and anatomical differences between the two. Single eyelids and heavy eyelids in humans are genetically related and generally remain unchanged throughout life. However, there are a few that change with age. In some cases, the single eyelid gradually changes to a heavy eyelid as they age into adulthood; in others, as they age, the eyelid skin loosens and sags, covering the original fold of the heavy eyelid and giving the impression of a single eyelid appearance. In humans, both upper eyelids are generally symmetrical, but about 2.85-8.89% of people have inconsistent upper eyelid morphology, with a single eyelid on one side and a blepharoplasty on the other. As far as the Oriental people are concerned, single eyelid and blepharoplasty are two different eyelid morphologies, and from the physiological point of view, both are normal and basically no difference. From a physiological point of view, both are normal and basically indistinguishable. However, from an aesthetic point of view, the single eyelid tends to give people the impression that their eyes are smaller and “less beautiful”. Functionally, the blepharoplasty is not as effective as the blepharoplasty in expressing emotion and revealing the eyes. Therefore, in addition to adding beauty, blepharoplasty has some functional significance, which is the main reason for blepharoplasty. From the point of view of morphology, the difference between single eyelid and blepharoplasty, in addition to the difference in the upper eyelid with or without transverse folds, the skin of the whole upper eyelid of the single eyelid is thicker and appears to be more bloated, the skin is mildly sagging, covering the lid margins, and when looking at the eyelid, the root of the eyelashes can not be seen; blepharoplasty of the upper eyelid is thinner, and the upper eyelid is cleaner, and the upper eyelid skin does not sag, and the margins of the eyelids are all visible. The skin of the upper eyelid does not droop and the margins of the eyelids are fully visible. The eyelashes of a single lid are short and sparse. When looking at the eyelid, the eyelashes tend to tilt downward, and sometimes the eyelashes cover the pupil, affecting the field of vision and visual acuity. In blepharoplasty, the eyelashes are longer and slightly curved upwards when viewed flatly. The inner canthus of single eyelid patients is rounded due to the presence of a canthus, while the inner canthus of blepharoplasty patients is generally pointed and usually without a canthus. As the occurrence of single and heavy eyelids is affected by race, region, heredity, age and other factors, there is a significant difference in morphology, and thus there is also a significant difference in its anatomical structure. The skin of the single lid is thicker, the subcutaneous tissue is higher, the orbicularis oculi muscle is more developed, and the fat behind the orbicularis oculi muscle is more; the lid of the single-lid person is thin and narrow, and the muscle that opens the eye – the levator muscle is not well developed; and the heavy lid person is just the opposite. The orbital compartment is generally low in single lids, and orbital fat may prolapse on the upper lid margin or anterior lid, whereas in blepharoplasty, the orbital compartment is high and there is no prolapse of orbital fat on the upper lid margin or anterior lid. Based on the anatomical structure, the skin and orbicularis oculi muscle in front of the lid cannot follow the lid when the eye is opened in a single eyelid, and thus the upper lid cannot form a crease as a single eyelid. When the eyes are opened, the skin and orbicularis oculi muscle below the blepharoplasty line in front of the lids can be lifted together with the lids, and a crease appears on the upper eyelid, which is manifested as double eyelids. From the difference between single and blepharoplasty, the blepharoplasty that is often mentioned is actually a surgical procedure that modifies and reorganizes the anatomical structure of the single eyelid based on the principle of aesthetics, and finally shapes it into the appearance of a blepharoplasty. What kind of person is suitable for blepharoplasty: Anyone who is physically healthy, mentally normal, and has no contraindications to surgery for single eyelids or loose eyelid skin is suitable for surgery. What kind of eyes are not suitable for blepharoplasty: those who have a wide eye cleft, short round eyes, protruding eyeballs, strabismus, ptosis, after upper eyelid implantation, facial paralysis, mental anomalies, peculiar aesthetic viewpoints, unrealistic and unreasonable demands are not suitable for blepharoplasty. Common surgical methods and their advantages and disadvantages: the main submerged thread method and incision method 1, submerged thread method: is the use of small incisions, the suture buried in the subcutaneous method. Adapted to the upper eyelid orbital septum fat, skin thin and tight young people, also adapted to one side of the single eyelid or blepharoplasty, or adapted to blepharoplasty blepharoplasty after the eyelid crease local shallow or disappearance of remedial. The buried wire method can be divided into intermittent buried wire method and continuous buried wire method, its advantages and disadvantages are as follows: (1) intermittent buried wire method is easy to operate, trauma is light, the skin without scars, postoperative swelling and bruising is light, recovery is fast, generally 15 to 20 days after the operation of the basic swelling, the eyelids close to the natural. The disadvantage of this method is the appearance of nodules under the skin, and the eyelid crease can be maintained for a shorter period of time. (2) Continuous threading method is safe and reliable, with short operation time, little pain and fast swelling. Due to the continuous threading method of blepharoplasty, the contact points of the lid tissues or the fascia tissues in front of the plate are 6 to 10 (compared to only 3 to 6 in the intermittent threading method), which increases the area of adhesion between the skin and the eyelid tissues, therefore, the surgery is more reliable and has a higher rate of success. The intermittent method requires 3 to 5 knots, and after surgery, it is easy to form hard knots and affect the effect of blepharoplasty, while the continuous method has only one knot that can be buried deep under the skin, so it is not easy to form hard knots. 2, incision method: for swollen eyes, triangular eyes and other eye types. For the upper eyelid skin laxity, upper eyelid bloat, triangular eye and the inner canthus, the incision method to do blepharoplasty effect is the best, the buried wire method or suture method to do blepharoplasty after the effect is not ideal, can be used to remedy the method, and after the operation is not easy to recurrence of the single eyelid. However, the incision method is relatively more complicated, and the swelling time is relatively long, about 7 days after the removal of stitches, 15 days after the swelling, 3 to 6 months after the complete return to normal. Preoperative precautions: 1, two weeks before surgery, do not take drugs containing aspirin, because aspirin will make platelet coagulation function is reduced; 2, patients with hypertension and diabetes, should be in the initial consultation to inform the doctor inform the doctor of their condition, in order to respond to the doctor to confirm the surgical program; 3, to determine the health of the body before the operation, no infectious diseases or other inflammatory diseases; 4, do not wear makeup before the operation 5. Women should avoid menstruation. Post-operative precautions: 1, 7 days after the operation to avoid the surgery department as much as possible to get wet; 2, to ensure that the surgical site clean; 3, avoid eating stimulating foods such as chili peppers, etc.; 4, strictly comply with the doctor’s instructions to take medication and follow-up.