Hello, Welcome to HCM, The symptoms of Horners syndrome include a drooping eyelid, decreased pupil size and decreased sweating on the affected side of your face. Horner syndrome is not a disease itself it is a sign of medical problems such as stroke, tumor or spinal cord injury. It can be idiopathic also. There is no specific treatment for Horner syndrome. Treatment depends on the cause and it disappears when an underlying medical condition is effectively treated. If you are having difficulty seeing out of the affected eye, you have to consult the ophthalmologist for complete evaluation and treatment. Thank you.