The eyelid has a complex design, with eight layers sandwiched into a structure only a few millimeters thick. Abnormalities of eyelid position and function may develop when even a single layer becomes defective.
Eyelid malpositions and abnormal growths pose a serious threat to the integrity of the underlying eye and to the maintenance of normal vision. The main causes of such disorders include aging, cancer, trauma, birth defects, and complications from previous operations.
In contrast to cosmetic operations undertaken to improve on appearance, reconstructive eyelid surgery for the disorders noted below are designed with the primary goal of improving on the function of the eyelids as well as restoring and preserving the health of the eye. As such, most are covered by medical insurance.