Why is one eyelid double-lidded and the other single-lidded?

Generally, having one double eyelid and one single eyelid may be caused by genetic factors, aging, improper sleeping posture, poor eye usage habits, or blepharitis. If discomfort occurs, prompt medical consultation is recommended. Detailed explanations are as follows:

1. Genetic Factors

Genetic factors determine the appearance of the eyes, including whether the eyelids are single or double. If similar cases of one double eyelid and one single eyelid exist within the family, it is likely due to genetic inheritance. Usually, no treatment is necessary. However, for aesthetic purposes, suture technique for double eyelid surgery can be performed under a doctor's guidance. This involves inserting sutures between the upper eyelid skin and the tarsal plate to create adhesion and form a double eyelid. The general reference price for suture double eyelid surgery is 1000-3000 yuan per session. Improvement is usually noticeable within 1-2 weeks after surgery, but may be accompanied by mild swelling and bruising.

2. Aging

With increasing age, the skin around the eyes gradually becomes loose, and the elasticity of subcutaneous tissue and muscles weakens, potentially progressing asymmetrically in both eyes. This may cause the double eyelid fold on one side to become shallower or disappear, resulting in an appearance of one double eyelid and one single eyelid. Under a doctor's guidance, Korean-style three-point double eyelid surgery can be considered. This involves creating three small incisions on the eyelid, removing a small amount of fat through these incisions, and then suturing the dermis to the tarsal plate at three points to create a double eyelid. The general reference price for Korean-style three-point double eyelid surgery is 2000-6000 yuan per session. Improvement is usually noticeable within 2-3 weeks after surgery, but may be accompanied by local swelling and bruising.

3. Improper Sleeping Posture

Long-term unilateral lateral sleeping can compress one eye, possibly causing slight edema or poor blood circulation in the local tissue, making the existing double eyelid fold less noticeable and appearing as a single eyelid, while the other side remains normal. It is recommended to adjust sleeping posture, maintain supine or alternating lateral positions, and avoid prolonged pressure on one eye.

4. Poor Eye Usage Habits

For example, long-term excessive use of one eye, such as frequently using only one eye to look at close objects, may cause muscle tension in that eye, altering the eyelid shape and affecting the original double eyelid fold, while the other side remains relatively normal. Attention should be paid to eye hygiene in daily life, avoiding prolonged one-sided eye usage. Under a doctor's guidance, eye drops to relieve eye fatigue can be used, such as naphazoline hydrochloride and vitamin B12 eye drops, Corydalis yanhusuo eye drops, or compound chondroitin sulfate eye drops.

5. Blepharitis

Blepharitis is mainly caused by Staphylococcus infection of the meibomian glands, hair follicles of the eyelashes, and their associated glands, leading to local inflammatory reactions. When inflammation occurs on one eyelid, local redness, swelling, and pain may appear. Swelling can cause the double eyelid fold to disappear, creating a contrast with the normal eyelid on the other side, and may also be accompanied by increased eye secretions. Under a doctor's guidance, medications such as ofloxacin eye drops, chlortetracycline eye ointment, or tobramycin eye drops can be used for treatment.

It is recommended to visit a formal hospital and undergo the above procedures under the guidance of a qualified physician to ensure surgical safety and effectiveness. Postoperative care includes maintaining ocular cleanliness, avoiding contact with water, applying cold and hot compresses as instructed, ensuring adequate rest, and avoiding excessive eye use and strenuous activities.