what are double eyelids

Double eyelids are a type of eyelid that have a visible crease or fold of skin where the eye meets the eye socket. This crease divides the eyelid into two parts, hence the name "double eyelids". People with double eyelids can see creases in their eyelids when their eyes are open. Double eyelids are a normal variation and require no medical intervention. However, some people undergo cosmetic surgery to change their appearance. Double eyelid surgery, also known as Asian blepharoplasty, creates an upper eyelid crease. This surgery is the most common plastic surgery procedure in East Asia. In contrast, monolids, also known as single eyelids, do not have a visible crease between the eyelashes and eyebrows. The skin of the upper eyelid is smooth from the inner corner of the eye to the part of the eyebrow nearest to the nose, covering the innermost edge of the eyes. Monolids are a common characteristic found in some genetic conditions, such as Down syndrome.