Brow/Upper lid anatomy, aging and aesthetic analysis.

The upper eyelid serves the important anatomic function of protecting the eye and rewetting the cornea to maintain vision. The complex dynamic action of the upper eyelid explains its relatively complex anatomy. The brow has an important supportive role. Studies have revealed facial characteristics perceived as youthful and aged, and the anatomic basis of these changes is defined at many levels. Characteristic aging changes in the upper eyelid and brow create an appearance of aging and opportunities for functional and aesthetic improvement.