Walsh & Hoyt: Anatomy of the Eyelid System

The eyelids contain three main muscles innervated by three different neural networks. The oculomotor nerve provides innervation to the levator palpebrae superioris muscle that keeps the eyelids open, a function assisted somewhat by Mullers muscle which is innervated by the sympathetic nervous system. Eyelid closure is achieved by contraction of the orbicularis oculi muscle, innervated by the facial nerve.