###Human: Does drooping eyelid mean Horner's syndrome? ###Assistant: Hello. Horner syndrome is characterized by myosis (small pupil) and enophthalmos (eye turned inside) besides ptosis. It is usually associated with other symptoms like severe headache, dizziness, etc. So, I definitely do not think that you have this syndrome. As you do not have any other symptoms, there is no reason to worry about. In my opinion, it could be a normal face asymmetry. If you have double vision, especially at the end of the day, or if the ptosis is more visible at the end of the day compared to the morning, I would recommend performing nerve conduction studies in order to investigate for myasthenia gravis.