Neurology of the eyelids.

The role of eyelids is to provide maximal protection to the eyeball without interfering with vision. To accomplish this purpose, an intricate neural network coordinates the lid and eye movements. The lid-eye synkinesis is ultimately based on common innervation of the levator palpebrae superioris (LPS) and the superior rectus muscles. The LPS is variously affected in numerous neurologic disorders. Because the eyelids are readily accessible for inspection, and because they conform to the fundamental laws of neurophysiology, different syndromes of eyelid dysfunction are of great value in topologic diagnosis.