Ptosis (pronounced “toe-sis”) is the medical term for drooping of the upper eyelid(s). This lowering of the upper eyelid margin may cause a reduction in the field of vision when the eyelid either partially or completely obstructs the pupil. Patients with ptosis often have difficulty keeping their eyelids open. To compensate, they will often arch their eyebrows in an effort to raise the drooping eyelids. In severe cases, people with ptosis may need to lift their eyelids with their fingers in order to see. Children with ptosis may develop amblyopia (“lazy eye”) or developmental delay from limitation of their vision.