Upper eyelid anatomy: an update.

Eyelid surgery necessitates a thorough knowledge of eyelid anatomy. Recent contributions to the literature have significantly advanced our understanding of eyelid anatomy. In this review, we present an update of the anatomy and the implications for upper eyelid surgery. Aspects to be covered include the levator aponeurosis, Müller's muscle, lamina propria mucosae of conjunctiva, orbital septum, myoneural junction of the levator palpebrae superioris muscle, adipose tissue, and the ligament system.