Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language.

Horner Syndrome

Horner Syndrome
Horner Syndrome

This photo shows a person with Horner syndrome that affects the left eye. The left eyelid droops (called ptosis), and the left pupil is constricted (called miosis).

DR P. MARAZZI/SCIENCE PHOTO LIBRARY

Locations